2007 KN4LF Daily LF/MF/HF Radio Propagation Forecast Archive

FLYING FOR ME
2007
KN4LF DAILY LF/MF/HF
FREQUENCY RADIOWAVE PROPAGATION FORECAST ARCHIVE

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KN4LF Daily LF/MF/HF Frequency Radiowave Propagation Forecast #2007-013

Date Format is MM/DD/YYYY

Published Thursday 12/20/2007 At 2200 UTC Valid 12/21-27/2007

GLOBAL LF 30-300 KC PROPAGATION CONDITIONS EXPECTED-

POOR to FAIR.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

GLOBAL MF 300-3000 KC PROPAGATION CONDITIONS EXPECTED WITH AN EMPHASIS ON THE MF AM BROADCAST BAND, 160 METERS AND 120 METERS-

-Expect FAIR Northern Hemisphere domestic propagation conditions on east-west paths out to approximately 1100 miles.

*Expect POOR Hemisphere domestic conditions on north TO south paths out to approximately 1100 miles.

+Expect FAIR to GOOD Northern Hemisphere domestic conditions on south TO north paths out to approximately 1100 miles.

-Expect POOR Southern Hemisphere domestic propagation conditions on east-west paths out to approximately 1100 miles.

+Expect POOR to FAIR Southern Hemisphere domestic conditions on north TO south paths out to approximately 1100 miles.

*Expect POOR conditions on south TO north paths in the Southern Hemisphere out to approximately 1100 miles.

Equatorial region domestic propagation conditions out to approximately 1100 miles should be FAIR.

High latitude Northern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles should be POOR.

High latitude Southern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles should be POOR.

Mid latitude Northern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles should be FAIR.

Mid latitude Southern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles should be POOR.

Low latitude Northern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific propagation conditions in excess of approximately 3200 miles should be FAIR.

Low latitude Southern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific propagation conditions in excess of approximately 3200 miles should be POOR.

Equatorial region to Northern Hemisphere mid latitude propagation conditions in excess of approximately 3200 miles should be FAIR.

Equatorial region to Southern Hemisphere mid latitude propagation conditions in excess of approximately 3200 miles should be POOR.

Equatorial region to Northern Hemisphere high latitude propagation conditions in excess of approximately 3200 miles should be POOR.

Equatorial region to Southern Hemisphere high latitude propagation conditions in excess of 3200 miles should be POOR.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

GLOBAL HF 3000-30000 KC PROPAGATION CONDITIONS EXPECTED-

Lower frequency (80-30 meters) propagation conditions tend to be impacted in a negative manner not by the maximum usable frequency (MUF) along a particular propagation path and time but rather due to geomagnetic storms that increase signal absorption via the E layer (the altitude of the Radio Aurora). Also D layer signal absorption due elevated proton flux at energies greater than 10 MeV (10+0).

Higher frequency (20-10 meters) propagation conditions tend to be impacted in a negative manner by the maximum usable frequency (MUF) along a particular propagation path and time and to a lesser extent due to geomagnetic storms that increase signal absorption via the E layer (the altitude of the Radio Aurora). D layer signal absorption due elevated proton flux at energies greater than 10 MeV (10+0) is inconsequential on 20-10 meters.

Low: 0-25 degrees N/S

Mid: 25-60 degrees N/S

High: 60-90 degrees N/S

Low Latitude- POOR on 80-30 meters ham /90-31 meters shortwave.

Mid Latitude- FAIR on 80-30 meters ham/90-31 meters shortwave.

High Latitude- POOR on 80-30 meters ham/90-31 meters shortwave.

Low Latitude- FAIR on 20-17 meters ham/25-17 meters shortwave.

Mid Latitude- FAIR on 20-17 meters ham/25-17 meters shortwave.

High Latitude- FAIR to POOR 20-17 meters ham/25-17 meters shortwave.

Low Latitude- POOR on 15-10 meters ham/13-11 meters shortwave.

Mid Latitude- POOR on 15-10 meters ham/13-11 meters shortwave.

High Latitude- POOR on 15-10 meters ham/13-11 meters shortwave.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

GLOBAL HF 50-54 MC (6 METER) PROPAGATION MODES AND STRENGTHS ARE EXPECTED-

F2- NONE

Sporadic E- FAIR

Auroral E- POOR.

Tropospheric Ducting- FAIR to GOOD

Meteor Scatter- POOR

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

None-S0

For global real time information concerning 6 meter band openings check out the VHFDX website at:

http://www.vhfdx.net/spots/map.php?Frec=MUF

GLOBAL NOISE (QRN) OUTLOOK-

U.S. near real time lightning strike data:

http://thunderstorm.vaisala.com/explorer.html

A global view of near real time lightning strike data:

http://webflash.ess.washington.edu

During the outlook period there will be MODERATE thunderstorm lightning induced QRN levels in low latitude areas of the Northern hemisphere due to the proximity of the Inter Tropical Convergence Zone (ITCZ).

Northern hemisphere mid latitude regions can expect MODERATE to HIGH thunderstorm lightning induced QRN tied to fall season cold/warm/occluded fronts and associated extra-tropical cold core low pressure systems.

Northern hemisphere high latitude regions can expect LOW to MODERATE thunderstorm lightning induced QRN tied to fall season cold/warm/occluded fronts and associated extra-tropical cold core low pressure systems.

During the outlook period there will be HIGH thunderstorm lightning induced QRN levels in low latitude areas of the Southern Hemisphere due to the proximity of the Inter Tropical Convergence Zone (ITCZ) and tropical warm core low pressure systems.

Southern hemisphere mid latitude regions can expect HIGH to MODERATE thunderstorm lightning induced QRN tied to spring season cold/warm/occluded fronts and associated extra-tropical cold core low pressure systems and tropical warm core low pressure systems.

Southern hemisphere high latitude regions can expect MODERATE to LOW thunderstorm lightning induced QRN tied to spring season cold/warm/occluded fronts and associated extra-tropical cold core low pressure systems.

END OF FORECAST

DISCUSSION OF PAST CONDITIONS-

For 12/14-20/2007-

Per forecast #2007-012 the period began with exceptionally quiet conditions, then degraded to active by the middle of the period onward. Overall LF, MF and HF frequency propagation conditions were fair to poor.

A recurring southern hemisphere Coronal Hole #304 (old #300) became geoeffective (Earth facing) and the high velocity solar wind stream emanating from it was strong and the impact to propagation conditions was moderate.

Globally with the daily sunspot number as high as 39 and vaguely related solar flux level as high as 92, the Maximum usable Frequency (MUF) rose high enough to give 15, 17 and 20 meters a boost in propagation conditions via the F layer.

However F layer MUFs continued to low to boost propagation conditions on 6 and 10 meters.

The following propagation modes and strengths were observed on 6 meters.

F2- NONE

Sporadic E- FAIR

Auroral E- FAIR

Tropospheric Ducting- FAIR to GOOD

Meteor Scatter- GOOD

There were some Sporadic E (Es) propagation openings on 6-160 meters.

In the Northern Hemisphere due to seasonal chemical changes in the F layer of the ionosphere and therefore higher MUFs, there was significant east-west F layer propagation on 17 meters. There was also intermittent east-west F layer propagation openings on 15 meters.

In the Southern Hemisphere due to seasonal chemical changes in the F layer of the ionosphere and therefore lower MUFs, there was little east-west F layer propagation on 10, 12 and 15, meters. There was intermittent east-west F layer propagation openings on 17 meters.

There was one sunspot group visible, #10978 with a twisted beta-gamma-delta magnetic signature, which has since slipped around the western horizon of the Sun. While visible it produced 7 C class solar flares.

A brief bit of excitement occurred during the period as a Plage rotated around the eastern horizon of the Sun. It has at a mid latitude location and had a solar cycle 24 magnetic polarity. At least through today the Plage has not developed into a sunspot group. So alas we cannot yet declare that solar cycle 24 has begun.

After 18 days consecutively with visible sunspots on the Earth facing side of the Sun, yesterday the count fell to 0. Sunspots had also been visible on the far side of the Sun via the SOHO holographic image. Unfortunately all of the sunspot groups were old solar cycle 23 ones.

Trans-equatorial (TEP) HF propagation between North and South America occurred, as well as between southern Africa to Europe/West Asia and also Australia to Eastern Asia/Oceania.

There was moderate signal absorption on the MF AM broadcast band, 160 and 120 meters on high and low latitude propagation paths in the Northern Hemisphere. The moderate absorption degraded propagation conditions.

There was moderate signal absorption on the MF AM broadcast band, 160 and 120 meters on high and low latitude propagation paths in the Southern Hemisphere. The moderate absorption degraded propagation conditions.

There was moderate signal absorption on the LF band on high and low latitude paths in the Northern Hemisphere. The moderate absorption degraded propagation conditions.

There was moderate signal absorption on the LF band on high and low latitude propagation paths in the Southern Hemisphere. The moderate absorption degraded propagation conditions.

At times moderate lightning QRN hampered receive conditions on 160 and 80 meters in the Northern Hemisphere.

At times major lightning QRN hampered receive conditions on 160, 80 and 40 meters in the Southern Hemisphere.

DISCUSSION OF FUTURE CONDITIONS-

For 12/21-27/2007-

Recurrent southern hemisphere Coronal Hole #304 (old #300) will continue to impact propagation conditions in a moderate to minor negative manner through 12/22/2007.

Globally with the daily sunspot number and vaguely related solar flux level at low levels (<73), decreased F layer MUFs will negatively impact 15, 17 and 20 meters.

There will be a few Sporadic E (Es) propagation openings on 10-160 meters.

In the Northern Hemisphere due to seasonal chemical changes in the F layer of the ionosphere and therefore higher MUFs, there will be east-west F layer propagation on 17 meters. There will be intermittent east-west propagation openings on 15 meters.

In the Southern Hemisphere due to seasonal chemical changes in the F layer of the ionosphere and therefore lower MUFs, there will be little east-west F layer propagation on 10, 12 and 15, meters. However there will be intermittent east-west propagation openings on 17 meters.

The following old sunspot groups may rotate around the east limb of the Sun during the forecast period if they survived the back side transit: #10976 with a beta magnetic signature on 12/24/2007 and #10977 with a beta magnetic signature on 12/27/2007.

Trans-equatorial (TEP) HF propagation between North and South America will occur, as well between southern Africa to Europe/West Asia and also Australia to Eastern Asia/Oceania.

There will be moderate to minor signal absorption on the MF AM broadcast band, 160 and 120 meters on high and low latitude propagation paths in the northern hemisphere. The moderate to minor absorption will degrade propagation conditions.

There will be moderate signal absorption on the MF AM broadcast band, 160 and 120 meters on high and low latitude propagation paths in the Southern Hemisphere. The moderate absorption will degrade propagation conditions.

There will be moderate signal absorption on the LF band on high and low latitude paths in the Northern Hemisphere. The moderate signal absorption will degrade propagation conditions.

There will be moderate signal absorption on the LF band on high and low latitude propagation paths in the Southern Hemisphere. The moderate absorption will degrade propagation conditions.

At times major to moderate lightning QRN will hamper receive conditions on 160, 80 and 40 meters in the Northern Hemisphere?

At times major lightning QRN will hamper receive conditions on 160, 80, 40 and 20 meters in the Southern Hemisphere.

SOLAR, SPACE WEATHER AND GEOMAGNETIC CONDITIONS EXPECTED-

Kp 0-4, isolated 5.

During the period quiet (Kp 0-2) geomagnetic conditions WILL OCCUR.

During the period unsettled (Kp- 3) geomagnetic conditions WILL OCCUR.

During the period active (Kp- 4) geomagnetic conditions WILL OCCUR.

During the period minor (Kp- 5) geomagnetic storming conditions MAY OCCUR.

During the period moderate (Kp- 6) geomagnetic storming conditions WILL NOT OCCUR.

During the period strong (Kp- 7) geomagnetic storming conditions WILL NOT OCCUR.

During the period severe (Kp- 8) geomagnetic storming conditions WILL NOT OCCUR.

During the period extreme (Kp- 9) geomagnetic storming conditions WILL NOT OCCUR.

The chance of polar cap absorption on high latitude propagation paths due to excessive energetic protons >10 Mev (10+0) is LOW.

The chance of daylight side SID radio blackouts from solar flares is LOW.

The chance of a geoeffective (Earth facing) Coronal Mass Ejection (CME) is LOW.

The chance of a partially geoeffective (Earth facing) Coronal Mass Ejection (CME) is LOW.

The chance of a geoeffective (Earth facing) Coronal Hole is LOW.

Daily solar flux index levels (SFI) should range between 68-73.

The probability of a small C class solar flare is LOW.

The probability of a large M class solar flare is LOW.

The probability of a huge X class solar flare is LOW.

The NOAA/SEC Wang-Sheeley-Arge model forecasts the interplanetary magnetic field (IMF) polarity to be POSITIVE.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

SOLAR, SPACE WEATHER AND GEOMAGNETIC INDICES FOR THE PERIOD 2200 UTC 12/14/2007 TO 2200 UTC 12/20/2007

Sunspot Groups- Sunspot group #10978 contains a twisted beta-gamma-delta magnetic signature that was capable of producing small C class and moderate size M class solar flares.

Max/Min Solar Flux Readings- 72.5 to 91.9.

Max/Min SEC Sunspot Number- 00 to 39.

Max/Min Solar Wind Speed- 344 to 770.

Max/Min Averaged Daily Background X-Ray Flux- A0.0 to B1.1.

Max/Min Dst Index- -46 to +33, via Kyoto.

Max/Min Dst Index- -45 to -6, via G3YNK.

Solar Flares- C-7 M-0 X-0

Elevated Energetic Protons >10 MeV (10+0)- 0.

Recurring southern hemisphere Coronal Hole #304 (old #300) became geoeffective (Earth facing) and the high velocity solar wind stream emanating from it was strong and the impact to propagation conditions was moderately negative.

Geoeffective (Earth Facing) Coronal Mass Ejections- 0

Partially geoeffective (Earth Facing) Coronal Mass Ejections- 0

Polar cap absorption on high latitude propagation paths did not occur due to excessive energetic protons >10 Mev (10+0).

The Ap index had been at quiet geomagnetic levels to minor geomagnetic storming levels, with a range of 00-32.

The Kp index had been at quiet to active geomagnetic levels, with a range of 0 to 4.

The Boulder CO mid latitude K index had been at quiet geomagnetic levels to minor geomagnetic storming levels, with a range of 0 to 5.

The Fredericksburg, MD mid latitude K index had been at quiet to unsettled geomagnetic levels with a range of 0 to 3.

The College, AK high latitude K index had been at quiet geomagnetic levels to strong geomagnetic storming levels, with a range of 0 to 7.

The Troms, Norway high latitude K index had been at quiet geomagnetic levels to moderate geomagnetic storming levels, with a range of 0 to 6.

PROPAGATION LESSON-

From http://www.kn4lf.com/kn4lf8.htm

14. Sunspot Group-

Sunspot groups are bipolar magnetic concentration regions on the photosphere of the Sun where magnetic field strengths many thousands of times stronger than the Earth's magnetic field reside. Sunspots appear as dark spots on the surface of the Sun because temperatures in the dark centers of sunspots drop to approximately 3700 K compared to 5700 K for the surrounding photosphere. The difference in temperature makes the spots appear darker than elsewhere. Sunspots typically last for several days to several weeks. They are seen to rotate around the sun, since they are on the surface, and the sun rotates fully every 27.5 days.

Sunspots usually come in groups with two opposing sets of spots. Whether two or twenty sunspots exist in a particular group they are counted as one sunspot group and numbered, such as 10500. That number would signify sunspot group number 10500 for solar cycle 23.

One set of sunspots will have a positive or north magnetic field while the other set will have a negative or south magnetic field. The magnetic field is strongest in the darker parts of the sunspots called the umbra and weaker and more horizontal in the lighter part called the penumbra. The twisted magnetic fields associated with sunspot groups are one source of the solar flares, coronal mass ejections and geomagnetic storms that wreak havoc with the ionosphere here on Earth.

The current system of counting sun spots hails from a previous era when direct observation of sun spots was inherently inaccurate. The sunspot number is derived by counting 10 points for each sunspot group and then adding one point for each spot. So if a sunspot group contains 1 individual sunspot the official count becomes 11. 4 individual sunspots in a sunspot group equals 44 sunspots. (See definition #24. Plage).

SPACE WEATHER SCALES-

Kp Indices-

G5 = Extreme Storm - Kp = 9
G4 = Severe Storm - Kp = 8
G3 = Strong Storm - Kp = 7
G2 = Moderate Storm - Kp = 6
G1 = Minor Storm - Kp = 5
Active - Kp = 4
Unsettled - Kp = 3

Ap Indices-

Ap 100-400 Severe Storm
Ap 50-99 Major Storm
Ap 30-49 Minor Storm
Ap 16-29 Active
Ap 8-15 Unsettled
Ap 0-7 Quiet

Correlation Of Kp To Ap Indices-

K- 0= A- 0
K- 1= A- 3
K- 2= A- 7
K- 3= A- 15
K- 4= A- 27
K- 5= A- 48
K- 6= A- 80
K- 7= A- 140
K- 8= A- 240
K- 9= A- 400

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KN4LF Daily LF/MF/HF Frequency Radiowave Propagation Forecast #2007-012

Date Format is MM/DD/YYYY

Published Thursday 12/13/2007 At 2200 UTC Valid 12/14-20/2007

GLOBAL LF 30-300 KC PROPAGATION CONDITIONS EXPECTED-

GOOD to FAIR 12/14-16/2007.

FAIR to POOR 12/16-20/2007.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

GLOBAL MF 300-3000 KC PROPAGATION CONDITIONS EXPECTED WITH AN EMPHASIS ON THE MF AM BROADCAST BAND, 160 METERS AND 120 METERS-

-Expect GOOD to FAIR Northern Hemisphere domestic propagation conditions on east-west paths out to approximately 1100 miles.

*Expect GOOD to FAIR Hemisphere domestic conditions on north TO south paths out to approximately 1100 miles.

+Expect POOR to FAIR Northern Hemisphere domestic conditions on south TO north paths out to approximately 1100 miles.

-Expect FAIR to POOR Southern Hemisphere domestic propagation conditions on east-west paths out to approximately 1100 miles.

+Expect POOR Southern Hemisphere domestic conditions on north TO south paths out to approximately 1100 miles.

*Expect FAIR to POOR conditions on south TO north paths in the Southern Hemisphere out to approximately 1100 miles.

Equatorial region domestic propagation conditions out to approximately 1100 miles should be FAIR.

High latitude Northern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles should be GOOD to FAIR.

High latitude Southern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles should be FAIR to POOR.

Mid latitude Northern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles should be GOOD to FAIR.

Mid latitude Southern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles should be FAIR to POOR.

Low latitude Northern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific propagation conditions in excess of approximately 3200 miles should be GOOD to FAIR.

Low latitude Southern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific propagation conditions in excess of approximately 3200 miles should be FAIR to POOR.

Equatorial region to Northern Hemisphere mid latitude propagation conditions in excess of approximately 3200 miles should be GOOD to FAIR.

Equatorial region to Southern Hemisphere mid latitude propagation conditions in excess of approximately 3200 miles should be FAIR.

Equatorial region to Northern Hemisphere high latitude propagation conditions in excess of approximately 3200 miles should be GOOD to FAIR.

Equatorial region to Southern Hemisphere high latitude propagation conditions in excess of 3200 miles should be FAIR.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

GLOBAL HF 3000-30000 KC PROPAGATION CONDITIONS EXPECTED-

Low: 0-25 degrees N/S

Mid: 25-60 degrees N/S

High: 60-90 degrees N/S

Low Latitude- GOOD 12/14-16/2007. FAIR 12/17-20/2007 on 80-30 meters ham /90-31 meters shortwave.

Mid Latitude- GOOD to FAIR 12/14-16/2007. FAIR to POOR 12/17-20/2007 on 80-30 meters ham/90-31 meters shortwave.

High Latitude- FAIR 12/14-16/2007. POOR 12/17-20/2007 on 80-30 meters ham/90-31 meters shortwave.

Low Latitude- GOOD to FAIR 12/14-16/2007. FAIR to POOR 12/17-20/2007 on 20-17 meters ham/25-17 meters shortwave.

Mid Latitude- GOOD to FAIR 12/14-16/2007. FAIR to POOR 12/17-20/2007 on 20-17 meters ham/25-17 meters shortwave.

High Latitude- FAIR 12/14-16/2007. POOR 12/17-20/2007 on 20-17 meters ham/25-17 meters shortwave.

Low Latitude- GOOD to FAIR 12/14-16/2007. FAIR to POOR 12/17-20/2007 on 15-10 meters ham/13-11 meters shortwave.

Mid Latitude- FAIR 12/14-16/2007. POOR 12/17-20/2007 on 15-10 meters ham/13-11 meters shortwave.

High Latitude- POOR on 15-10 meters ham/13-11 meters shortwave.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

GLOBAL HF 50-54 MC (6 METER) PROPAGATION MODES AND STRENGTHS ARE EXPECTED-

F2- NONE

Sporadic E- FAIR

Auroral E- NONE 12/14-16-2007. FAIR 12/17-18/2007. NONE 12/18-20/2007.

Tropospheric Ducting- FAIR to GOOD

Meteor Scatter- FAIR to GOOD 12/14-15/2007. POOR to NONE 12/16-20/2007. This will be due to the Geminid meteor shower which peaks on Friday December 14, 2007.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

None-S0

For global real time information concerning 6 meter band openings check out the VHFDX website at:

http://www.vhfdx.net/spots/map.php?Frec=MUF

GLOBAL NOISE (QRN) OUTLOOK-

U.S. near real time lightning strike data:

http://thunderstorm.vaisala.com/explorer.html

A global view of near real time lightning strike data:

http://webflash.ess.washington.edu

END OF FORECAST

DISCUSSION OF PAST CONDITIONS-

For 12/07-13/2007-

Per forecast #2007-011 the period saw exceptionally quiet conditions. Towards the end of the period unsettled to active conditions occurred. Overall LF, MF and HF frequency propagation conditions were good.

A recurring transequatorial Coronal Hole #303 (old #298) became geoeffective (Earth facing) but the solar wind stream emanating from it was weak and the impact to propagation conditions was minimal.

Globally with the daily sunspot number as high as 44 and vaguely related solar flux level as high as 94, the Maximum usable Frequency (MUF) rose high enough to give 15, 17 and 20 meters a boost in propagation conditions via the F layer.

However F layer MUFs continued to low to boost propagation conditions on 6 and 10 meters.

The following propagation modes and strengths were observed on 6 meters.

F2- NONE

Sporadic E- FAIR

Auroral E- NONE

Tropospheric Ducting- FAIR to GOOD

Meteor- NONE

There were some Sporadic E (Es) propagation openings on 6-160 meters.

There were two new sunspot groups visible, #10977 with a simple beta magnetic signature, which has since slipped around the western horizon of the Sun. Also significant sunspot group #10978 with a twisted beta-gamma-delta magnetic signature that so far has produced two small C class solar flares.

We have now reached 12 days consecutively with visible sunspot groups on the Earth facing side of the Sun. Sunspot groups had also been visible on the far side of the Sun via the SOHO holographic image. Unfortunately all of the sunspot groups were old solar cycle 23 ones.

Trans-equatorial (TEP) HF propagation between North and South America occurred, as well as between southern Africa to Europe/West Asia and also Australia to Eastern Asia/Oceania.

There was nil signal absorption on the MF AM broadcast band, 160 and 120 meters on high latitude propagation paths in the Northern Hemisphere. The nil absorption allowed for some of the best propagation conditions in a good while.

There was minor signal absorption on the MF AM broadcast band, 160 and 120 meters on high latitude propagation paths in the Southern Hemisphere. The minor absorption allowed for improved propagation conditions.

There was nil signal absorption on the LF band on high latitude paths in the Northern Hemisphere. The nil absorption allowed for some of the best propagation conditions in a good while.

There was minor signal absorption on the LF band on high latitude propagation paths in the Southern Hemisphere. The minor absorption allowed for improved propagation conditions.

At times moderate lightning QRN hampered receive conditions on 160 and 80 meters in the Northern Hemisphere.

At times major lightning QRN hampered receive conditions on 160, 80 and 40 meters in the Southern Hemisphere.

DISCUSSION OF FUTURE CONDITIONS-

For 12/14-20/2007-

Recurrent southern hemisphere Coronal Hole #304 (old #300) will rotate into geoeffective (Earth facing) position beginning on 12/14/2007. It will impact propagation conditions in a moderate negative manner beginning on 12/16-17/2007.

Globally with the daily sunspot number and vaguely related solar flux level at a continued moderate levels, increased F layer MUFs will positively impact 15, 17 and 20 meters.

There will be a few Sporadic E (Es) propagation openings on 10-160 meters.

The following old sunspot groups may rotate around the east limb of the Sun during the forecast period if they survived the back side transit: #10975 on 12/14/2007.

Current sunspot group #10978 with a twisted beta-gamma-delta magnetic signature has the potential to produce moderate sized M class solar flares.

Trans-equatorial (TEP) HF propagation between North and South America will occur, as well between southern Africa to Europe/West Asia and also Australia to Eastern Asia/Oceania.

There will be moderate signal absorption beginning on 12/17/2007 on the MF AM broadcast band, 160 and 120 meters on high latitude propagation paths in the northern hemisphere. The moderate absorption will degrade propagation conditions.

There will be moderate signal absorption beginning on 12/17/2007 on the MF AM broadcast band, 160 and 120 meters on high latitude propagation paths in the Southern Hemisphere. The moderate absorption will degrade propagation conditions.

There will be moderate signal absorption beginning on 12/17/2007 on the LF band on high latitude paths in the Northern Hemisphere. The moderate absorption will degrade propagation conditions.

There will be moderate signal absorption beginning on 12/17/2007 on the LF band on high latitude propagation paths in the Southern Hemisphere. The moderate absorption will degrade propagation conditions.

At times major lightning QRN will hamper receive conditions on 160, 80 and 40 meters in the Northern Hemisphere.

At times major lightning QRN will hamper receive conditions on 160, 80, 40 and 20 meters in the Southern Hemisphere.

SOLAR, SPACE WEATHER AND GEOMAGNETIC CONDITIONS EXPECTED-

Kp 0-5, isolated 6.

During the period quiet (Kp 0-2) geomagnetic conditions WILL OCCUR.

During the period unsettled (Kp- 3) geomagnetic conditions WILL OCCUR.

During the period active (Kp- 4) geomagnetic conditions WILL OCCUR.

During the period minor (Kp- 5) geomagnetic storming conditions WILL OCCUR.

During the period moderate (Kp- 6) geomagnetic storming conditions MAY OCCUR.

During the period strong (Kp- 7) geomagnetic storming conditions WILL NOT OCCUR.

During the period severe (Kp- 8) geomagnetic storming conditions WILL NOT OCCUR.

During the period extreme (Kp- 9) geomagnetic storming conditions WILL NOT OCCUR.

The chance of polar cap absorption on high latitude propagation paths due to excessive energetic protons >10 Mev (10+0) is LOW.

The chance of daylight side SID radio blackouts from solar flares is LOW to MODERATE.

The chance of a geoeffective (Earth facing) Coronal Mass Ejection (CME) is LOW to MODERATE.

The chance of a partially geoeffective (Earth facing) Coronal Mass Ejection (CME) is LOW to MODERATE.

The chance of a geoeffective (Earth facing) Coronal Hole is HIGH, southern hemisphere CH #304 (old #300) beginning on 12/14/2007.

Daily solar flux index levels (SFI) should range between 90-96.

The probability of a small C class solar flare is MODERATE.

The probability of a large M class solar flare is LOW to MODERATE.

The probability of a huge X class solar flare is LOW.

The NOAA/SEC Wang-Sheeley-Arge model forecasts the interplanetary magnetic field (IMF) polarity to be NEGATIVE between 12/14-18/2007 and POSITIVE between 12/18-20/2007.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

SOLAR, SPACE WEATHER AND GEOMAGNETIC INDICES FOR THE PERIOD 2200 UTC 12/07/2007 TO 2200 UTC 12/13/2007

Sunspot Groups- Sunspot group #10978 contains a twisted beta-gamma-delta magnetic signature that was capable of producing small C class and moderate size M class solar flares.

Max/Min Solar Flux Readings- 80.8 to 94.4. This is the highest daily solar flux level since November 2006.

Max/Min SEC Sunspot Number- 22 to 44

Max/Min Solar Wind Speed- 270 to 684

Max/Min Averaged Daily Background X-Ray Flux- A1.7 to C4.5

Max/Min Dst Index- -36 to +20, via Kyoto

Max/Min Dst Index- -30 to -6, via G3YNK

Solar Flares- C-3 M-0 X-0

Elevated Energetic Protons >10 MeV (10+0)- 0

A recurring transequatorial Coronal Hole #303 (old #298) became geoeffective (Earth facing) but the solar wind stream emanating from it was weak and the impact to propagation conditions was minimal.

Geoeffective (Earth Facing) Coronal Mass Ejections- 0

Partially geoeffective (Earth Facing) Coronal Mass Ejections- 0

Polar cap absorption on high latitude propagation paths did not occur due to excessive energetic protons >10 Mev (10+0).

The Ap index had been at quiet to active geomagnetic levels, with a range of 00-22.

The Kp index had been at quiet to active geomagnetic levels, with a range of 0 to 4.

The Boulder CO mid latitude K index had been at quiet to active geomagnetic levels, with a range of 0 to 4.

The high latitude K index (via Troms, Norway) had been at quiet geomagnetic levels to moderate geomagnetic storming levels, with a range of 0 to 6.

PROPAGATION LESSON-

From http://www.kn4lf.com/kn4lf8.htm

13.) Polar Cap Absorption (PCA)-

An anomalous condition of the polar Ionosphere whereby medium frequency (300-3000 kc) radio waves are absorbed, and LF and VLF (3-300 kHz) radio waves are wave guided at lower altitudes than normal. In practice, the absorption is inferred from the proton flux at energies greater than 10 MeV (10+0), so that PCA's, Polar Radio Blackouts and Proton Events are interrelated and often simultaneous.

((((NOTE!!! high latitude radio propagation paths may still be disturbed for days, up to weeks, following the end of an official proton event.)))) This fact is still stubbornly opposed by some otherwise very knowledgeable space weather physicists, hung up on threshold Riometer readings.

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KN4LF Daily LF/MF/HF Frequency Radiowave Propagation Forecast #2007-011

Date Format is MM/DD/YYYY

Published Thursday 12/06/2007 At 2200 UTC Valid 12/07-13/2007

GLOBAL LF 30-300 KC PROPAGATION CONDITIONS EXPECTED-

FAIR to GOOD.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

GLOBAL MF 300-3000 KC PROPAGATION CONDITIONS EXPECTED WITH AN EMPHASIS ON THE MF AM BROADCAST BAND, 160 METERS AND 120 METERS-

If the background solar flux level rises into the B range from the current A 5.0 level, MF propagations will not be quite as good as I currently have forecasted.

-Expect GOOD Northern Hemisphere domestic propagation conditions on east-west paths out to approximately 1100 miles.

*Expect FAIR to GOOD Hemisphere domestic conditions on north TO south paths out to approximately 1100 miles.

+Expect FAIR to POOR Northern Hemisphere domestic conditions on south TO north paths out to approximately 1100 miles.

-Expect FAIR Southern Hemisphere domestic propagation conditions on east-west paths out to approximately 1100 miles.

+Expect POOR Southern Hemisphere domestic conditions on north TO south paths out to approximately 1100 miles.

*Expect FAIR conditions on south TO north paths in the Southern Hemisphere out to approximately 1100 miles.

Equatorial region domestic propagation conditions out to approximately 1100 miles should be FAIR.

High latitude Northern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles should be GOOD.

High latitude Southern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles should be FAIR.

Mid latitude Northern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles should be GOOD.

Mid latitude Southern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles should be FAIR.

Low latitude Northern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific propagation conditions in excess of approximately 3200 miles should be GOOD.

Low latitude Southern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific propagation conditions in excess of approximately 3200 miles should be FAIR.

Equatorial region to Northern Hemisphere mid latitude propagation conditions in excess of approximately 3200 miles should be GOOD.

Equatorial region to Southern Hemisphere mid latitude propagation conditions in excess of approximately 3200 miles should be FAIR.

Equatorial region to Northern Hemisphere high latitude propagation conditions in excess of approximately 3200 miles should be GOOD.

Equatorial region to Southern Hemisphere high latitude propagation conditions in excess of 3200 miles should be FAIR.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

GLOBAL HF 3000-30000 KC PROPAGATION CONDITIONS EXPECTED-

Low: 0-25 degrees N/S

Mid: 25-60 degrees N/S

High: 60-90 degrees N/S

Low Latitude- FAIR to GOOD on 80-30 meters ham /90-31 meters shortwave.

Mid Latitude- GOOD on 80-30 meters ham/90-31 meters shortwave.

High Latitude- GOOD to FAIR on 80-30 meters ham/90-31 meters shortwave.

Low Latitude- FAIR on 20-17 meters ham/25-17 meters shortwave.

Mid Latitude- FAIR to GOOD on 20-17 meters ham/25-17 meters shortwave.

High Latitude- FAIR to GOOD on 20-17 meters ham/25-17 meters shortwave.

Low Latitude- POOR on 15-10 meters ham/13-11 meters shortwave.

Mid Latitude- POOR to FAIR on 15-10 meters ham/13-11 meters shortwave.

High Latitude- POOR to FAIR on 15-10 meters ham/13-11 meters shortwave.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

GLOBAL HF 50-54 MC (6 METER) PROPAGATION MODES AND STRENGTHS ARE EXPECTED-

F2- NONE

Sporadic E- FAIR

Auroral E- NONE

Tropospheric Ducting- FAIR to GOOD

Meteor Scatter- POOR

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

None-S0

For global real time information concerning 6 meter band openings check out the VHFDX website at:

http://www.vhfdx.net/spots/map.php?Frec=MUF

GLOBAL NOISE (QRN) OUTLOOK-

U.S. near real time lightning strike data:

http://thunderstorm.vaisala.com/explorer.html

A global view of near real time lightning strike data:

http://webflash.ess.washington.edu

During the outlook period there will be MODERATE thunderstorm lightning induced QRN levels in low latitude areas of the Northern hemisphere due to the proximity of the Inter Tropical Convergence Zone (ITCZ).

Northern hemisphere mid latitude regions can expect LOW to MODERATE thunderstorm lightning induced QRN tied to fall season cold/warm/occluded fronts and associated extra-tropical cold core low pressure systems.

Northern hemisphere high latitude regions can expect LOW to NIL thunderstorm lightning induced QRN tied to fall season cold/warm/occluded fronts and associated extra-tropical cold core low pressure systems.

END OF OUTLOOK

DISCUSSION OF PAST CONDITIONS-

For 11/30-12/06/2007-

Per forecast #2007-010 the period saw quiet conditions. Actually at times conditions were exceptionally quiet!

A new southern hemisphere small Coronal Hole #302 formed but the solar wind stream emanating from it was too weak to impact propagation conditions in a negative manner.

Globally with the daily sunspot number and vaguely related solar flux level low, reduced F layer MUFs negatively impacted 6, 10, 12, 15 and 17 meters.

The following propagation modes and strengths were observed on 6 meters.

F2- NONE

Sporadic E- FAIR

Auroral E- NONE

Tropospheric Ducting- FAIR to GOOD

Meteor- NONE

There were some Sporadic E (Es) propagation openings on 10-160 meters.

There were three new sunspot groups visible, #10976 with a beta magnetic signature, #10977 with a beta magnetic signature and a recurrent but newly numbered sunspot group #10978 (old 10974) with a beta-gamma magnetic signature, that has just risen above the eastern horizon of the Sun.

However the solar flux index did not exceed 77 and the sunspot number was no higher than 26, so there was no HF propagation boost on 10-17 meters during the period but a bit did occur on 20 meters.

We have now reached 6 days consecutively with visible sunspot groups on the Earth facing side of the Sun. Sunspot groups had also been visible on the far side of the Sun via the SOHO holographic image. Unfortunately all of the sunspot groups were old solar cycle 23 ones.

Trans-equatorial (TEP) HF propagation between North and South America occurred, as well as between southern Africa to Europe/West Asia and also Australia to Eastern Asia/Oceania.

There was nil signal absorption on the LF band on high latitude paths in the Northern Hemisphere. The nil absorption allowed for some of the best propagation conditions in a good while.

There was minor signal absorption on the LF band on high latitude propagation paths in the Southern Hemisphere. The minor absorption allowed for improved propagation conditions.

At times moderate lightning QRN hampered receive conditions on 160 and 80 meters in the Northern Hemisphere.

At times major lightning QRN hampered receive conditions on 160, 80 and 40 meters in the Southern Hemisphere.

DISCUSSION OF FUTURE CONDITIONS-

For 12/07-13/2007-

Recurrent transequatorial Coronal Hole #303 (old #298) will rotate into geoeffective (Earth facing) position beginning on 12/08/2007. It could impact propagation conditions in a very minor negative manner beginning on 12/11/2007.

Globally with the daily sunspot number and vaguely related solar flux level low, reduced F layer MUFs will negatively impact 6, 10, 12, 15 and 17 meters. However 20 meter propagation could see a bit of a boost.

The following propagation modes and strengths will occur on 6 meters.

F2- NONE

Sporadic E- FAIR

Auroral E- NONE

Tropospheric Ducting- FAIR to GOOD

Meteor Scatter- NONE

There will be a few Sporadic E (Es) propagation openings on 10-160 meters.

The following old sunspot groups may rotate around the east limb of the Sun during the forecast period if they survived the back side transit:

Recurrent but newly renumbered sunspot group #10978 (old 10974) with a beta-gamma magnetic signature, that has just risen above the eastern horizon of the Sun. It has the potential to produce C class solar flares and wreck the second half of my forecast.

Trans-equatorial (TEP) HF propagation between North and South America will occur, as well between southern Africa to Europe/West Asia and also Australia to Eastern Asia/Oceania.

I expect nil signal absorption on the MF AM broadcast band, 160 and 120 meters on high latitude propagation paths in the northern hemisphere. The nil absorption will allow for some of the best propagation conditions in a good while.

There will be minor signal absorption on the MF AM broadcast band, 160 and 120 meters on high latitude propagation paths in the Southern Hemisphere. The minor absorption will allow for improved propagation conditions.

There will be nil signal absorption on the LF band on high latitude paths in the Northern Hemisphere. The nil absorption will allow for some of the best propagation conditions in a good while.

There will be minor signal absorption on the LF band on high latitude propagation paths in the Southern Hemisphere. The minor absorption will allow for improved propagation conditions.

At times moderate lightning QRN will hamper receive conditions on 160 and 80 meters in the Northern Hemisphere.

At times major lightning QRN will hamper receive conditions on 160, 80 and 40 meters in the Southern Hemisphere.

SOLAR, SPACE WEATHER AND GEOMAGNETIC CONDITIONS EXPECTED-

Kp 0-3, isolated Kp-4.

During the period quiet (Kp 0-2) geomagnetic conditions WILL OCCUR.

During the period unsettled (Kp- 3) geomagnetic conditions WILL OCCUR.

During the period active (Kp- 4) geomagnetic conditions MAY OCCUR.

During the period minor (Kp- 5) geomagnetic storming conditions WILL NOT OCCUR.

During the period moderate (Kp- 6) geomagnetic storming conditions WILL NOT OCCUR.

During the period strong (Kp- 7) geomagnetic storming conditions WILL NOT OCCUR.

During the period severe (Kp- 8) geomagnetic storming conditions WILL NOT OCCUR.

During the period extreme (Kp- 9) geomagnetic storming conditions WILL NOT OCCUR.

The chance of polar cap absorption on high latitude propagation paths due to excessive energetic protons >10 Mev (10+0) is LOW.

The chance of daylight side SID radio blackouts from solar flares is LOW but will become MODERATE.

The chance of a geoeffective (Earth facing) Coronal Mass Ejection (CME) is LOW but will become MODERATE.

The chance of a partially geoeffective (Earth facing) Coronal Mass Ejection (CME) is LOW but will become MODERATE.

The chance of a geoeffective (Earth facing) Coronal Hole is HIGH, transequatorial CH #303 (old #298), between 12/08-11/2007.

Daily solar flux index levels (SFI) should range between 77-85.

The probability of a small C class solar flare is LOW but will become MODERATE.

The probability of a large M class solar flare is LOW

The probability of a huge X class solar flare is LOW.

The NOAA/SEC Wang-Sheeley-Arge model forecasts the interplanetary magnetic field (IMF) polarity to be NEGATIVE.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

SOLAR, SPACE WEATHER AND GEOMAGNETIC INDICES FOR THE PERIOD 2200 UTC 11/30/2007 TO 2200 UTC 12/06/2007

Sunspot Groups- No partially or totally geoeffective (Earth Facing) sunspot groups contained a twisted magnetic signature capable of producing large M class and huge X class solar flares.

Max/Min Solar Flux Readings- 71.4 to 77.4

Max/Min SEC Sunspot Number- 00 to 26

Max/Min Solar Wind Speed- 272 to 371

Max/Min Averaged Daily Background X-Ray Flux- A0.0 to A5.0

Max/Min Dst Index- -13 to +16, via Kyoto

Max/Min Dst Index- -17 to -8, via G3YNK

Solar Flares- C-0 M-0 X-0

Elevated Energetic Protons >10 MeV (10+0)- 0

Geoeffective (Earth Facing) Coronal Mass Ejections- 0

Partially geoeffective (Earth Facing) Coronal Mass Ejections- 0

A new southern hemisphere small Coronal Hole #302 formed but the solar wind stream emanating from it was too weak to impact propagation conditions in a negative manner.

Polar cap absorption on high latitude propagation paths did not occur due to excessive energetic protons >10 Mev (10+0).

The Ap index had been at quiet geomagnetic levels, with a range of 00-06.

The Kp index had been at quiet geomagnetic levels, with a range of 0 to 2.

The Boulder CO mid latitude K index had been at quiet geomagnetic levels, with a range of 0 to 2.

The high latitude K index (via Troms, Norway) had been at quiet to active geomagnetic levels, with a range of 0 to 4.

PROPAGATION LESSON-

From http://www.kn4lf.com/kn4lf8.htm

12.) Geological/Meteorological Effects On Medium Frequency Propagation-

Geological effects such as earthquakes and volcanic eruptions, as well as meteorological effects such as Troposphere originating Internal Buoyancy/Gravity Waves (IBGW's), Stratosphere level Quasi Biennial Oscillations (QBO) and warming (STRATWARM) have a negative effect on medium frequency RF signals in the form of small to medium increased absorption variations of medium frequency RF signals via the D layer, due to traveling ionospheric disturbances (TID's).

Also temperature and moisture discontinuities involved with cold frontal inversions and air mass triple points involved with extra-tropical low pressure systems can refract, diffract or scatter medium frequency radio signals in unpredictable ways, most notably on high transmitted RF power levels. This is another concept that a fellow Physicist and expert in optics took me to task over.

As far as medium frequency refraction it's more significant at say 3000 kc, then 1850 kc or 1500 kc. But it's also more noticeable with higher transmitted RF powers, i.e. WSAI 1530 50 KW and even more so with BSKA 1521 KC 1000 KW and now defunct 2000 kc region 100 KW marine stations.

We know that the medium frequency spectrum is defined as 300-3000 kc but the differences in refractive properties between 300 and 3000 is very significant At 3000 kc refraction is a good description, on 160 scattering, at 300 kc diffraction.

Using the strictest definition of RF refraction, its effect on 160 meters is small but it has been measured by government researchers as significant enough to impact 160 but near the air mass triple point. In my opinion scattering is actually the more consistent propagation medium for 160 meters along a cold front, away from the extra-tropical cyclone center.

However the temperature and moisture discontinuities in the vicinity of a triple point air mass structure such as seen with a mature extra-tropical cyclone is very complex and fluid. The NW quadrant of the extra-tropical cyclone is the location that the original government researchers identified as the region of existence for the complex temperature/moisture discontinuity structure that allows for refraction of RF signals as low as 1500 kc. I have not been successful at garnering data from the federal government that can be released to the general public. NOAA has been similarly stymied and therefore is now conducting similar research.

The QBO is a wind shift in the equatorial stratosphere, an oscillation from easterly to westerly and back on the time scale of approximately two years (26 months) and is a source of Internal Buoyancy/Gravity Waves (IBGW) which create absorptive perturbations in the D and E layers and even possibly the F 1/2 layer. A note, the E-valley/Flayer ducting propagation mechanism does not exist only during greyline periods. Internal Buoyancy/Gravity Waves (IBGW's) are a source of the ducting mechanism and allow for occurrences of ducting along any propagation path in total darkness. Measurement of the timing of arrival of propagated medium frequency RF signals demonstrates the existence of the ducting mechanism, versus conventional numerous E layer land/ocean surface hops.

The HAARP ionospheric program, earthquakes, volcanic eruptions, thunderstorms, lightning (especially positive cloud to ground strokes), elves, tornadoes and hurricanes and even man made activities such as rocket launches including the space shuttle, are all sources of (IBGW's).

Many times I've heard ham's lament that propagation was going to go to crap due to another NASA Space Shuttle launch, in a sense they are correct.

Back To The Top

KN4LF Daily LF/MF/HF Frequency Radiowave Propagation Forecast #2007-010

Date Format is MM/DD/YYYY

Published Thursday 11/29/2007 At 2200 UTC Valid 11/30-12/06/2007

GLOBAL LF 30-300 KC PROPAGATION CONDITIONS EXPECTED-

POOR to FAIR between 11/30-12/01/2007.

FAIR to GOOD between 12/02-06/2007.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

GLOBAL MF 300-3000 KC PROPAGATION CONDITIONS EXPECTED WITH AN EMPHASIS ON THE MF AM BROADCAST BAND, 160 METERS AND 120 METERS-

-Expect FAIR to GOOD Northern Hemisphere domestic propagation conditions on east-west paths out to approximately 1100 miles.

*Expect FAIR to GOOD Hemisphere domestic conditions on north TO south paths out to approximately 1100 miles.

+Expect GOOD to FAIR Northern Hemisphere domestic conditions on south TO north paths out to approximately 1100 miles.

-Expect POOR to FAIR Southern Hemisphere domestic propagation conditions on east-west paths out to approximately 1100 miles.

+Expect POOR to FAIR Southern Hemisphere domestic conditions on north TO south paths out to approximately 1100 miles.

*Expect POOR to FAIR conditions on south TO north paths in the Southern Hemisphere out to approximately 1100 miles.

Equatorial region domestic propagation conditions out to approximately 1100 miles should be POOR to FAIR.

High latitude Southern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles should be POOR between 11/30-12/01/2007, then becoming FAIR between 12/02-06/2007.

Mid latitude Southern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles should be POOR between 11/30-12/01/2007, then becoming FAIR between 12/02-06/2007.

Low latitude Northern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific propagation conditions in excess of approximately 3200 miles should be FAIR to GOOD.

Low latitude Southern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific propagation conditions in excess of approximately 3200 miles should be POOR to FAIR.

Equatorial region to Northern Hemisphere mid latitude propagation conditions in excess of approximately 3200 miles should be FAIR to GOOD.

Equatorial region to Southern Hemisphere mid latitude propagation conditions in excess of approximately 3200 miles should be POOR to FAIR.

Equatorial region to Northern Hemisphere high latitude propagation conditions in excess of approximately 3200 miles should be POOR to FAIR between 11/30-12/01/2007, then becoming FAIR to GOOD between 12/02-06/2007.

Equatorial region to Southern Hemisphere high latitude propagation conditions in excess of 3200 miles should be POOR between 11/30-12/01/2007, then becoming FAIR between 12/02-06/2007.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

GLOBAL HF 3000-30000 KC PROPAGATION CONDITIONS EXPECTED-

Low: 0-25 degrees N/S

Mid: 25-60 degrees N/S

High: 60-90 degrees N/S

Low Latitude- FAIR between 11/30-12/01/2007, then becoming GOOD between 12/02-06/2007on 80-30 meters.

Mid Latitude- FAIR between 11/30-12/01/2007, then becoming GOOD between 12/02-06/2007on 80-30 meters.

High Latitude- POOR to FAIR between 11/30-12/01/2007, then becoming FAIR to GOOD between 12/02-06/2007on 80-30 meters.

Low Latitude- POOR to FAIR between 11/30-12/01/2007, then becoming FAIR to GOOD between 12/02-06/2007 on 20-17 meters.

Mid Latitude- POOR to FAIR between 11/30-12/01/2007, then becoming FAIR to GOOD between 12/02-06/2007 on 20-17 meters.

High Latitude- POOR to FAIR between 11/30-12/01/2007, then becoming FAIR to GOOD between 12/02-06/2007 on 20-17.

Low Latitude- FAIR on 15-10 meters.

Mid Latitude- POOR to FAIR on 15-10 meters.

High Latitude- POOR on 15-10 meters.

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

GLOBAL HF 50-54 MC (6 METER) PROPAGATION MODES AND STRENGTHS EXPECTED-

F2-NONE

Sporadic E- POOR

Auroral E-NONE

Tropospheric Ducting- FAIR to GOOD

Meteor Scatter- NONE

For global real time information concerning 6 meter band openings check out the VHFDX website at: http://www.vhfdx.net/spots/map.php?Frec=MUF

Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3

None-S0

GLOBAL NOISE (QRN) OUTLOOK-

U.S. near real time lightning strike data:

http://thunderstorm.vaisala.com/explorer.html

A global view of near real time lightning strike data:

http://webflash.ess.washington.edu

During the outlook period there will be HIGH thunderstorm lightning induced QRN levels in low latitude areas of the Northern hemisphere due to the proximity of the Inter Tropical Convergence Zone (ITCZ) and tropical warm core low pressure systems.

Northern hemisphere mid latitude regions can expect MODERATE thunderstorm lightning induced QRN tied to fall season cold/warm/occluded fronts and associated extra-tropical cold core low pressure systems.

Northern hemisphere high latitude regions can expect LOW thunderstorm lightning induced QRN tied to fall season cold/warm/occluded fronts and associated extra-tropical cold core low pressure systems.

Southern hemisphere mid latitude regions can expect HIGH TO MODERATE thunderstorm lightning induced QRN tied to spring season cold/warm/occluded fronts and associated extra-tropical cold core low pressure systems and tropical warm core low pressure systems.

Southern hemisphere high latitude regions can expect MODERATE TO LOW thunderstorm lightning induced QRN tied to spring season cold/warm/occluded fronts and associated extra-tropical cold core low pressure systems.

END OF OUTLOOK

DISCUSSION OF PAST CONDITIONS-

For 11/23-29/2007-

Per forecast #2007-009 the period saw quiet to occasionally active conditions. The source for the active conditions was a high velocity solar wind stream emanating from geoeffective (Earth facing) southern Coronal Hole #300 (#296).

Globally with the daily sunspot number and vaguely related solar flux level very low, reduced F layer MUFs negatively impacted 6, 10, 12, 15, 17 and 20 meters.

The following propagation modes and strengths were observed on 6 meters.

F2- NONE

Sporadic E- FAIR

Auroral E- NONE

Tropospheric Ducting- FAIR to GOOD

Meteor Scatter- NONE

There were very few Sporadic E (Es) propagation openings on 10-160 meters.

In the Northern Hemisphere due to seasonal chemical changes in the F layer of the ionosphere and therefore higher MUFs, there was significant east-west F layer propagation on 17 meters. There were intermittent east-west propagation openings on 15 meters.

In the Southern Hemisphere due to seasonal chemical changes in the F layer of the ionosphere and therefore lower MUFs, there was little east-west F layer propagation on 10, 12 and 15, meters. However there were intermittent east-west propagation openings on 17 meters.

There was one brief sunspot group visible, #10975 with a beta magnetic signature but the solar flux index did not exceed 71 and the sunspot number was no higher than 15, so there was no HF propagation boost on 10-20 meters during the period. We have now reached 3 days consecutively with no visible sunspot groups on the Earth facing side of the Sun. No sunspot groups had been visible on the far side of the Sun either via the SOHO holographic image.

Trans-equatorial (TEQ) HF propagation between North and South America occurred, as well as between southern Africa to Europe/West Asia and also Australia to Eastern Asia/Oceania.

There was minor signal absorption on the MF AM broadcast band, 160 and 120 meters on high latitude propagation paths in the Northern Hemisphere. The minor absorption allowed for improved propagation conditions.

There was minor to moderate signal absorption on the MF AM broadcast band, 160 and 120 meters on high latitude propagation paths in the Southern Hemisphere. The moderate absorption produced continued poor propagation conditions.

There was moderate to major signal absorption on the LF band on high and mid latitude paths. The major absorption produced continued poor propagation conditions.

At times intense lightning QRN hampered receive conditions on 160, 80 and 40 meters.

DISCUSSION OF FUTURE CONDITIONS-

For 11/30-12/06/2007-

No recurrent significant Coronal Holes will rotate into geoeffective (Earth facing) position. However a couple of new but insignificant in size transequatorial Coronal Holes (#301 & #302) will rotate into geoeffective (Earth facing) position be by 11/30/2007 but should not impact propagation conditions in a negative manner.

Globally with the daily sunspot number and vaguely related solar flux level very low, reduced F layer MUFs will negatively impact 6, 10, 12, 15, 17 and 20 meters.

The following propagation modes and strengths will occur on 6 meters.

F2- NONE

Sporadic E- FAIR

Auroral E- NONE

Tropospheric Ducting- FAIR to GOOD

Meteor Scatter- NONE

There will be very few Sporadic E (Es) propagation openings on 10-160 meters.

The following old sunspot groups may rotate around the east limb of the Sun during the forecast period if they survived the back side transit: None.

Trans-equatorial (TEQ) HF propagation between North and South America will occur, as well between southern Africa to Europe/West Asia and also Australia to Eastern Asia/Oceania.

I expect minor to nil signal absorption on the MF AM broadcast band, 160 and 120 meters on high latitude propagation paths in the northern hemisphere. This should lead to continued improvement in propagation conditions, especially in comparison to last week.

I expect moderate to minor signal absorption on the MF AM broadcast band, 160 and 120 meters on high latitude propagation paths in the southern hemisphere. The moderate absorption will produce continued poor propagation conditions.

I expect minor to nil signal absorption on the LF band on high latitude paths in the northern hemisphere. This should lead to continued improvement in propagation conditions, especially in comparison to last week.

I expect minor to nil signal absorption on the LF band on high latitude paths in the northern hemisphere. This should lead to improvement in propagation conditions.

Occasionally high thunderstorm lightning QRN levels will continue to plague amateur radio operations on 160, 80, 60 and 40 meters.

Occasionally high thunderstorm lightning QRN levels will continue to plague SWL radio operations on 120, 90, 60 and 49 meters.