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KN4LF DAILY LF/MF/HF/6M FREQUENCY RADIOWAVE PROPAGATION FORECAST #2008-13
Date Format is MM/DD/YYYY.
Published Friday 03/28/2008 at 1800 UTC Valid Saturday-Friday 03/29-04/04/2008
CONTEST INFORMATION-
1 contest is scheduled for the weekend of Saturday-Sunday 03/29-30, 2008. It is the very popular CQ Worldwide WPX SSB Contest. For more information check out the WA7BNM Contest website at http://www.hornucopia.com/contestcal/weeklycont.php .
GLOBAL LF 30-300 KC PROPAGATION CONDITIONS EXPECTED WITH EMPHASIS ON LF AM BROADCAST BAND-
There exists a long distance “daytime” propagation medium between approximately 30-100 kc. The transmitted signal wave guides between the D layer and the surface of the Earth.
Some day time sky wave propagation does occur between approximately 100-300 kc via the E layer, especially at higher latitudes in the winter time and at the bottom of a solar cycle.
Reception is tied to the density of the D layer, as well as the E layer at radio aurora altitude. Geomagnetic storming will suppress night time reception of signals but enhance day time reception of signals. High power broadcasters are more readily heard than low power ham radio signals.
Northern Hemisphere Night Time- POOR.
Southern Hemisphere Night Time- POOR.
Propagation Forecast
Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3
None- S0
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 Northern 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 GOOD TO FAIR Southern Hemisphere domestic conditions on north to south paths out to approximately 1100 miles.
*Expect POOR Southern Hemisphere conditions on south to north paths out to approximately 1100 miles.
-Expect FAIR Equatorial domestic propagation conditions on east-west paths out to approximately 1100 miles.
High latitude Northern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific and cross equatorial propagation conditions in excess of approximately 3200 miles will 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 will 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 will 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 will be FAIR.
Low latitude Northern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific propagation conditions in excess of approximately 3200 miles will be FAIR.
Low latitude Southern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans Pacific propagation conditions in excess of approximately 3200 miles will be FAIR.
Equatorial region to Northern Hemisphere mid latitude propagation conditions in excess of approximately 3200 miles will be FAIR.
Equatorial region to Southern Hemisphere mid latitude propagation conditions in excess of approximately 3200 miles will be FAIR.
Equatorial region to Northern Hemisphere high latitude propagation conditions in excess of approximately 3200 miles will be POOR.
Equatorial region to Southern Hemisphere high latitude propagation conditions in excess of 3200 miles will be POOR.
Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3
None- S0
GLOBAL F/F2 LAYER HF 3000-30000 KC PROPAGATION CONDITIONS EXPECTED-
Lower frequency HF (80-30 meters) propagation conditions are impacted in a negative manner not by variations in 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 increases in the lowest usable frequency (LUF) via D layer signal absorption due to elevated background solar flux levels and proton flux levels at energies greater than 10 MeV (10+0).
Higher frequency (20-10 meters) propagation conditions are impacted in a negative manner by variations in the maximum usable frequency (MUF) along a particular propagation path and time due to the current sunspot number and also due to geomagnetic storms. D layer signal absorption due to elevated proton flux at energies greater than 10 MeV (10+0) and elevated background solar flux levels, is usually but not always inconsequential on 20-10 meters.
Low Latitude- POOR TO FAIR between 03/29-31/2008, FAIR TO GOOD between 04/01-04/2008 on 80-30 meters ham/90-31 meters shortwave.
Mid Latitude- FAIR between 03/29-31/2008, GOOD between 04/01-04/2008 on 80-30 meters ham/90-31 meters shortwave.
High Latitude- POOR between 03/29-31/2008, FAIR between 04/01-04/2008 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 on 20-17 meters ham/25-17 meters shortwave.
Low Latitude- POOR to FAIR on 15 meters ham/13 meters shortwave.
Mid Latitude- POOR to FAIR on 15 meters ham/13 meters shortwave.
High Latitude- POOR to FAIR on 15 meters ham/13 meters shortwave.
Low Latitude- POOR on 12-10 meters ham/11 meters shortwave.
Mid Latitude- POOR on 12-10 meters ham/11 meters shortwave.
High Latitude- POOR on 12-10 meters ham/11 meters shortwave.
Note!!! At times propagation conditions on 12-10 meters ham/11 meters shortwave will be FAIR to GOOD, via the less predictable Sporadic E (Es) and Trans Equatorial (TEP) propagation modes.
Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3
None- S0
GLOBAL HF 50-54 MC (6 METER) PROPAGATION MODES AND STRENGTHS EXPECTED-
F2- NO
Sporadic E- YES/GOOD
Auroral E- YES/FAIR
Tropospheric Ducting- YES/GOOD
Meteor Scatter- YES/FAIR
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
A good source of information concerning 6 meter band openings via tropospheric ducting in the U.S. is at:
http://www.dxinfocentre.com/tropo.html
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
Northern hemisphere
low latitude regions can expect MODERATE thunderstorm lightning induced QRN tied
to the Spring season proximity of cold/warm/occluded fronts and associated
extra-tropical cold core low pressure systems, as well as the Inter Tropical
Convergence Zone (ITCZ).
Northern Hemisphere mid latitude regions can expect MODERATE to HIGH
thunderstorm lightning induced QRN tied to Spring 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 Spring season cold/warm/occluded
fronts and associated extra-tropical cold core low pressure systems.
Southern Hemisphere
low latitude regions can expect MODERATE thunderstorm lightning induced QRN tied
to the Fall season proximity of cold/warm/occluded fronts and associated
extra-tropical cold core low pressure systems, Inter Tropical Convergence Zone
(ITCZ) and tropical warm core low pressure systems.
Southern 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, as well as
tropical warm core low pressure systems.
Southern 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.
END OF FORECAST
SOLAR, SPACE WEATHER AND GEOMAGNETIC CONDITIONS EXPECTED-
For 03/29-04/04/2008-
Recurrent transequatorial Coronal Hole #319 (old #316) will become geo-effective (Earth facing) and the associated high velocity solar wind stream emanating from it will be strong and the impact to propagation conditions moderate beginning on Friday 04/04/2008.
Globally with the daily sunspot number at ~60 and vaguely related solar flux level at ~90, increased F layer MUFs will positively impact 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, 15 and 12 meters. There will be intermittent east-west propagation openings on 10 meters. Simultaneous short path/long path propagation echoing will occur.
In the Southern 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, 15 and 12 meters. There will be intermittent east-west propagation openings on 10 meters. Simultaneous short path/long path propagation echoing will occur.
Sunspot group #’s 10987 (old #10984), 10988 and 10989 will contain a Beta twisted magnetic field capable of producing small sized C class and medium sized M class solar flares.
The following old sunspot group may rotate around the east limb of the Sun during the forecast period if it 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 to 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 minor to moderate absorption will degrade propagation conditions.
There will be minor to moderate signal absorption on the MF AM broadcast band, 160 and 120 meters on high, mid and low latitude propagation paths in the Southern Hemisphere. The minor to moderate absorption will degrade propagation conditions.
There will be minor to moderate signal absorption on the LF band on high and low latitude paths in the Northern Hemisphere. The minor to moderate absorption will degrade propagation conditions.
There will be minor to moderate signal absorption on the LF band on high, mid and low latitude propagation paths in the Southern Hemisphere. The minor to moderate absorption will degrade propagation conditions.
High lightning QRN will hamper receive conditions on 160/120, 80/75 and 41/40 in the Northern Hemisphere.
High lightning QRN will hamper receive conditions on 160/120, 80/75 and 41/40 in the Southern Hemisphere.
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 Sudden Ionospheric Disturbances (SID) radio blackouts from solar flares is MODERATE.
The chance of a geoeffective (Earth facing) Coronal Mass Ejection (CME) is MODERATE.
The chance of a partially geoeffective (Earth facing) Coronal Mass Ejection (CME) is MODERATE.
The chance of a geoeffective (Earth facing) Coronal Hole is HIGH.
Daily maximum/minimum solar flux index levels (SFI) should range between 85 and 80.
The probability of a small C class solar flare is HIGH.
The probability of a large M class solar flare is MODERATE.
The probability of a huge X class solar flare is LOW.
When the Interplanetary Magnetic Field (IMF) polarity is negative the probability of geomagnetic storming on Earth increases. The NOAA/SWPC Wang-Sheeley-Arge model forecasts the Interplanetary Magnetic Field (IMF) polarity to be NEGATIVE.
PAST SOLAR, SPACE WEATHER AND GEOMAGNETIC CONDITIONS-
For 03/22-28/2008-
Per forecast #2008-12 the
period saw propagation conditions ranging from poor to good on LF, MF and HF
frequencies. Also per forecast #2008-12 via solar
imagery I expected #10987 (old #10984) to make a grand reappearance but did not
expect formation of #10988 and #10989. I've been watching old Sol for 35 years
as both a professional and amateur and have to say that I was a bit surprised at
the sudden outburst of activity.
Globally with the daily sunspot number as high as 63 and vaguely related solar flux level as high as 89, the Maximum Usable Frequency (MUF) rose high enough to give 10, 12, 15, 17 and 20 meters a boost in propagation conditions via the F2 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- YES/FAIR
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, 15, 12 and 10 meters. Simultaneous short path/long path propagation echoing occurred.
In the Southern 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, 15, 12 and 10 meters. Simultaneous short path/long path propagation echoing occurred.
Yesterday 03/27/2008 it was very good to
see some high bands activity occur. The increase in sunspots really improved
propagation conditions on 12 and 10 meters. There was a huge F2 opening on 10
meters between the U.S. and Oceania (ZL, H44), South America and Europe. 12
meters had an even more widespread F2 opening. Even 6 meters was open but the
propagation was via Sporadic E (Es) and Auroral E.
On 12 meters I worked H44MS in the Solomon Islands using 10 watts SSB to a
simple dipole up at 35 feet and the 5T5DC Mauritania DXpedition with 100 watts.
When you operate close to the Maximum Usable Frequency (MUF) D layer signal
absorption is lower and you ca work the worlds on a wet noodle.
There were 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 GONG holographic image.
Sunspot group #’s 10987 (old #10984), 10988 and 10989 contained a Beta twisted magnetic field capable of producing small sized C class and medium sized M class solar flares.
On Tuesday 03/25/2008 between 1848-1914 UTC sunspot group #10987 (old #10984) produced an M1.7 class solar flare. It had and associated SID HF fadeout as high as 11, 000 kc in North and South America.
New northern hemisphere Coronal Hole #317, as well as recurrent transequatorial Coronal Hole #318 (old #315) became geo-effective (Earth facing) during the forecast period and the associated high velocity solar wind stream emanating from them was strong and the impact to propagation conditions moderate to at times major.
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, medium 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, medium and low latitude propagation paths in the Southern Hemisphere. The moderate absorption degraded propagation conditions.
High lightning QRN (static) hampered receive conditions on 160/120, 80/75 and 41/40 in the Northern Hemisphere.
High lightning QRN (static) hampered receive conditions on 160/120, 80/75 and 41/40 in the Southern Hemisphere.
Max/Min Solar Flux Readings- 88.6 to 69.4.
Max/Min Background Solar Flux Readings- A8.1 to A0.0.
Max/Min SWPC Sunspot Number- 63 to 00.
Max/Min Solar Wind Speed- 719 to 342.
Max/Min DST via Kyoto- -44 to +22.
Max/Min DST via G3YNK- -55 to -15.
Solar Flares- C-0 M-1 X-0
Elevated Energetic Protons >10 MeV (10+0)- None.
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 major geomagnetic storming levels, with a range of 00-67.
The Kp index had been at quiet geomagnetic levels to moderate geomagnetic storming levels, with a range of 0 to 6.
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 geomagnetic levels to minor geomagnetic storming levels, with a range of 0 to 5.
The College (Fairbanks), 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 strong geomagnetic storming levels, with a range of 0 to 7.
The Australia Region K index had been at quiet to active geomagnetic levels, with a range of 1 to 4.
PROPAGATION LESSON-
From http://www.kn4lf.com/kn4lf8.htm
4.) Coronal
Mass Ejection (CME)-
A Coronal Mass Ejection is the name given to an ejection of a large amount of
matter from the Sun's outer atmosphere or corona. These ejections typically
comprise millions of tons of material in the form of charged particles and can
be seen because the material reflects sunlight. When one of these ejections is
directed towards the Earth (or conversely, directly away from the Earth), it
looks like a roughly circular "halo" surrounding the blanked out Sun.
The "Halo CME's" are those CME's which are more likely to impact the Earth than
those which are shot out at right angles to the Earth-Sun line. Energetic
protons emitted during CME's play a major role in increased day time and
night-time D layer absorption of medium frequencies.
Coronal Mass Ejections were once thought to be completely initiated by solar
flares. However it is now known that many (CME's) are not associated with Solar
Flares but instead with collapsing Solar Filaments. If a (CME) collides with the
Earth, it can excite a Geomagnetic Storm if the polarity of the Interplanetary
Magnetic Field (IMF) has a negative sign. We must be vigilant in watching for
geo-effective (CME's), in order to not be caught by surprise with a seemingly
sudden and unexpected Geomagnetic Storm. (See definition #6. Solar Filament).
(See definition #11. Geomagnetic/Ionospheric Storm). (See definition #16. Solar
Flare).
Coronal Mass Ejections are not random meaningless eruptions but instead a process by which the Sun expels complex magnetic signatures enroute to changing its magnetic polarity or said a different way the swapping of the Sun's magnetic poles. Basically the Sun swapped its magnetic polarity at the peak of present solar cycle 23 somewhere between July 2000 and December 2001. The next polarity swap will occur during solar cycle 24 somewhere around 2012.
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 -20 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 is best.
Standard Disclaimer-
Note! I use error prone RAW public domain data from the NOAA Space Environment Center, as well as other U.S. government organizations, to produce my propagation forecasts. This data is gathered and made public by the U.S. Government using taxpayer $$$. However the forecast that I produce from the RAW public domain data is my personal intellectual property. Therefore the propagation outlooks contained herein is copyrighted © 1988-2008 by Thomas F. Giella, KN4LF. Reproduction of and distribution of information herein is allowed without advanced permission as long as proper credit is given.
Also space weather forecasting is still an inexact science. The forecasts are not official but for hobby related purposes only and are subject to human error and acts of God, therefore no guarantee or warranty implied.