2008
KN4LF DAILY LF/MF/HF/6M
FREQUENCY RADIOWAVE PROPAGATION FORECAST #03

KN4LF Daily LF/MF/HF/6M Frequency Radiowave Propagation Forecast #2008-03

Date Format is MM/DD/YYYY

Published Friday 01/18/2008 At 1900 UTC Valid Saturday-Friday 01/19-25/2008

7 contests are scheduled for the weekend of Saturday-Sunday 01/19-24, 2008. For more information check out the WA7BNM Contest website at http://www.hornucopia.com/contestcal/weeklycont.php .

The big ones as far as my personal digital modes interests is the UK RTTY DX Contest and the Feld Hell (Hellschreiber) Sprint.

GLOBAL NIGHT TIME LF 30-300 KC PROPAGATION CONDITIONS EXPECTED WITH EMPHASIS ON LF AM BROADCAST BAND-

POOR between 01/19-21/2008, FAIR between 01/22-23/2008, GOOD between 01/24-25/2008 in the Northern Hemisphere.

POOR between 01/19-21/2008, FAIR between 01/22-25/2008 in the Southern Hemisphere.

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

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 to 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 POOR to FAIR.

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 POOR to 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 to FAIR.

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- FAIR 01/19-20/2008 then GOOD 01/21-25/2008 on 80-30 meters ham /90-31 meters shortwave.

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

High Latitude- FAIR 01/19-20/2008 then GOOD 01/21-25/2008 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- NO

Sporadic E- YES/FAIR

Auroral E- YES/FAIR

Tropospheric Ducting- YES/GOOD

Meteor Scatter- NO

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 Winter 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 Winter season cold/warm/occluded fronts and associated extra-tropical cold core low pressure systems.

During the outlook period there will be MODERATE to 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 Summer 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 Summer season cold/warm/occluded fronts and associated extra-tropical cold core low pressure systems.

END OF FORECAST

DISCUSSION OF PAST CONDITIONS-

For 01/12-18/2008-

Per forecast #2008-02 the period was unsettled to at times active. Overall LF and MF frequency propagation conditions were poor to fair and HF frequency propagation conditions were fair to good.

Globally with the daily sunspot number at 0 and vaguely related solar flux level no higher than 76, the Maximum Usable Frequency (MUF) did not rise high enough to give 6, 10, 12, 15, 17 and 20 meters a boost in propagation conditions via the F layer.

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

F2- NO

Sporadic E- YES/FAIR

Auroral E- YES/FAIR

Tropospheric Ducting- YES/GOOD

Meteor Scatter- NO

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

None-S0

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.

We saw 9 days consecutively with no visible sunspots on the Earth facing side of the Sun. However sunspots had been visible on the far side of the Sun via the SOHO holographic image.

No sunspot groups had a twisted magnetic field capable of producing small sized C class, medium sized M class and large sized X class solar flares.

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 to high lightning QRN (static) hampered receive conditions on 160, 80, 40 30 and 20 meters in the Northern Hemisphere.

High lightning QRN hampered receive conditions on 160, 80, 40, 30 and 20 meters in the Southern Hemisphere.

DISCUSSION OF FUTURE CONDITIONS-

For 01/19-25/2008

A recurrent Northern Hemisphere Coronal Hole #309 (old #305) will become geo-effective (Earth facing) and the associated high velocity solar wind stream emanating from it will be minor and the impact to propagation conditions will be minor.

Globally with the daily sunspot number at ~0 and vaguely related solar flux level at low levels (~73), decreased F layer MUFs will negatively impact 6, 10, 12, 15, 17 and 20 meters.

There will be a few 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 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.

No sunspot groups will contain a twisted magnetic field capable of producing small sized C class, medium sized M class and large sized X class solar flares.

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 (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 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 minor absorption will at times 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 minor signal absorption on the LF band on high and low latitude paths in the Northern Hemisphere. The minor absorption will at times 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 high lightning QRN will hamper receive conditions on 160, 80, 40, 30 and 20 meters in the Northern Hemisphere.

High lightning QRN will hamper receive conditions on 160, 80, 40, 30 and 20 meters in the Southern Hemisphere.

SOLAR, SPACE WEATHER AND GEOMAGNETIC CONDITIONS EXPECTED-

Kp 0-3, isolated 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.

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 HIGH.

Daily solar flux index levels (SFI) should range between 69-73.

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 Saturday 01/12/2008 To Friday 01/18/2007

Sunspot Groups- No sunspot groups had a twisted magnetic field capable of producing small sized C class, medium sized M class and large sized X class solar flares.

Max/Min Solar Flux Readings- 72.8 to 75.7.

Max/Min SWPC Sunspot Number- 00 to 00.

Max/Min Solar Wind Speed- 367 to 770.

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

Max/Min Dst Index- -69 to -1, via Kyoto.

Max/Min Dst Index- -34 to -25, via G3YNK.

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

Elevated Energetic Protons >10 MeV (10+0)- None.

A recurring southern Coronal Hole #308 (old #304) became geoeffective (Earth facing), the associated high velocity solar wind stream emanating from it was moderate and the impact to propagation conditions moderate.

Geoeffective (Earth Facing) Coronal Mass Ejections- None

Partially geoeffective (Earth Facing) Coronal Mass Ejections- None

Polar cap absorption on high latitude propagation paths due to excessive energetic protons >10 Mev (10+0)- None.

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 to active geomagnetic levels, with a range of 0 to 4.

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

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

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

18.) Sporadic-E (Es) Absorption, Blocking & Refraction-

Just as the E layer is the main refraction medium for medium frequency (300-3000 kc) signal propagation within approximately 5000 km/3100 mi, so is a Sporadic-E (Es) cloud. Sporadic-E (Es) clouds occur at approximately 100 km/60 miles in altitude and generally move from ESE to WNW.

Like Stratosphere level warming and Troposphere level temperature and moisture discontinuities, Sporadic-E  (Es) clouds can depending on the circumstances absorb, block or refract medium, high and very high frequency RF signals in an unpredictable manner.

The main source for "high latitude" Sporadic E (Es) clouds is geomagnetic storming induced radio aurora activity.

The main source for "mid latitude" Sporadic-E  (Es) clouds is wind shear produced by internal buoyancy/gravity waves (IBGW's), that create traveling ionosphere disturbances (TID's), most of which are produced by severe thunderstorm cell complexes with overshooting tops that penetrate into the Stratosphere. Another tie in between Sporadic-E (Es) and a severe thunderstorm is the Elve.

The main sources for "low latitude" Sporadic-E  (Es) clouds is wind shear produced by internal buoyancy/gravity waves (IBGW's), that create traveling ionosphere disturbances, most of which are produced by severe thunderstorm cell complexes tied to tropical cyclones. High electron content in the Equatorial Ring Current also plays a role.

The forecasting of Sporadic-E (Es) clouds has long been considered to be impossible. However it is possible to identify certain troposphere level meteorological conditions that can lead to the formation of Sporadic E (Es) clouds. One is as mentioned above the severe thunderstorm cell complex.

Sporadic-E (Es) clouds have been observed to initially occur within approximately 150 km/90 mi to the right of a severe thunderstorm cell complex in the northern hemisphere, with the opposite being observed in the southern hemisphere. To complicate matters is the fact that Sporadic-E (Es) clouds that initially form to the right of a severe thunderstorm complex in the northern hemisphere, then move from ESE-WNW and end up to the left of the severe thunderstorm complex in the northern hemisphere. So one has to look for Sporadic-E (Es) clouds on either side of a severe thunderstorm cell complex. Things get even more complicated when two severe thunderstorm cell complexes exist approximately 1000- 2000 miles apart.

Not all thunderstorm cell complexes reach severe levels and not all severe thunderstorm cell complexes produce Sporadic-E (Es). This is where knowledge in tropospheric physics and weather analyses/forecasting is necessary. Coincidentally I have a B.S. in Meteorology and an M.S. in Space Plasma Physics and am qualified to identify which severe thunderstorm cell complexes are most likely to produce Sporadic-E (Es) clouds.

Some of the key elements in identifying which severe thunderstorm cell complexes have the potential to produce Sporadic-E (Es) via wind shear, from internal buoyancy/gravity waves, that produce traveling ionosphere disturbances include:

1.) Negative tilted mid and upper level long wave troughs.

2.) Approximate 150 knot/170 mph jet stream jet maxes that produce divergence and therefore create a sucking vacuum effect above thunderstorm cells, that assist thunderstorm cells in reaching and penetrating the Tropopause into the Stratosphere.

3.) 500 mb temperatures of -20 deg. C or colder, which produce numerous positive and negative lightning bolts and inter-related Sprites and Elves.

4.) Approximate 150-175 knot/172-200 mph updrafts within thunderstorm cells complexes that create overshooting tops that penetrate the Tropopause into the Stratosphere (See definition #20 on Stratospheric Warming), launching upwardly propagating internal buoyancy/gravity waves, which create traveling ionosphere disturbances and then wind shear.

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

GENERAL GUIDELINES CONCERNING CORRELATION OF PROPAGATION INDICES TO ACTUAL MF/HF PROPAGATION CONDITIONS.

NOTE!!!  The propagation indices "interpretations" are my personal intellectual property. Therefore the propagation indices interpretations contained herein is copyrighted © 1988-2008 by Thomas F. Giella, KN4LF, all rights reserved. Reproduction of information herein is allowed without permission in advance as long as proper credit is given.

1.) Dropping indices numbers are better.

2.) A solar flux of 150 or higher, 200+ best, for medium frequencies under 100, under 70 best.

Keep in mind though that the 10.7 cm (2800 mhz) solar flux index is not a "reliable" gauge of ionization in our atmosphere for F layer medium frequency refractions, as the energy of photons at this frequency is to low on the order of one million times. However most are used to solar flux and sunspot number and it's a hard habit to break. A better indicator is the background X-Ray Flux. See #7 below.

3.) Solar flux of at least 150 for E Valley/F Layer ducting mechanism.

4.) Previous 24 hour Ap index under 10, under 7 for several days consecutively is best.

5.) Previous 3 hour Kp index under 3 for mid latitude paths, under 2 for high latitude paths, 0-1 for several days consecutively is best.

6.) Energetic protons no greater then 10 MeV (10+0).

7.) Background X-Ray flux levels less than A1 for several days consecutively.

8.) No current STRATWARM alert.

9.) Interplanetary Magnetic Field (IMF) Bz with a (positive number) sign, indicates a lesser chance of high latitude path Auroral absorption/unpredictable refraction or scattering of medium frequency RF signals, when the Kp is above 3.

10.) A -50 or better towards a positive number Dst index during the recovery time after a Geomagnetic Storm, as related to the Equatorial Ring Current. A positive number best.