KN4LF Daily LF/MF/HF Radio Propagation Outlook #2004-006
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Date Format is MM/DD/YYYY
Published Friday 12/10/2004 At 0200 UTC Valid 12/10-16/2004
During the period 12/10-11 quiet to unsettled (Kp 1-3) geomagnetic conditions
"WILL OCCUR".
During the period 12/11-12 active to minor (Kp 4-5) geomagnetic storming is
"PROBABLE".
During the period 12/11-12 moderate to major (Kp 6-7) geomagnetic storming is
"POSSIBLE".
During the period 12/13-16 unsettled to active (Kp 3-4) geomagnetic conditions
are"PROBABLE".
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 radio blackouts from solar flares is low.
GLOBAL LF UNDER 300 KC PROPAGATION CONDITIONS EXPECTED-
Daytime- Fair.
Nighttime- Poor, Becoming Very Poor on 12/12.
GLOBAL HF 3000-30000 KC PROPAGATION CONDITIONS EXPECTED-
Low Latitude- Good, Becoming Fair On 12/12, Back To Good On 12/13.
Mid Latitude- Good, Becoming Fair To Poor On 12/12, Back To Fair On 12/13.
High Latitude- Fair, Becoming Poor On 12/12, Then Back To Fair On 12/13.
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, becoming poor on 12/12, then back to fair on 12/14.
*Expect fair domestic conditions on north "TO" south paths in the "Northern
Hemisphere" out to approximately 1100 miles, becoming poor on 12/12, then back
to fair on 12/14.
+Expect Fair domestic conditions on south "TO" north paths in the "Northern
Hemisphere" out to approximately 1100 miles, becoming good on 12/12, then back
to fair on 12/14.
-Expect poor "Southern Hemisphere" domestic propagation conditions on east-west
paths.
+Expect fair domestic conditions on north "TO" south paths in the "Southern
Hemisphere" out to approximately 1100 miles, becoming good on 12/12, then back
to fair on 12/14.
*Expect poor conditions on south "TO" north paths in the "Southern Hemisphere"
out to approximately 1100 miles, becoming very poor on 12/12, then back to poor
on 12/14.
Equatorial region domestic propagation conditions out to approximately 1100
miles should be fair to good.
"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 fair, becoming poor on 12/12, then back to
fair on 12/14.
"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, becoming very poor on 12/12, then back
to poor on 12/14.
"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, then becoming fair on 12/11, back to
good on 12/14.
"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, then becoming poor on 12/12, then back
to fair on 12/14.
"Low latitude" Northern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP)
Trans Pacific propagation conditions in excess of approximately 3200 miles
should be good, then becoming fair on 12/12, then back to fair on 12/14.
"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 then becoming fair on
12/13, then back to good on 12/14.
Equatorial region to Southern Hemisphere "mid latitude" propagation conditions
in excess of 3200 miles should be good, then becoming fair on 12/13, then back
to good on 12/14.
Equatorial region to Northern Hemisphere "high latitude" propagation conditions
in excess of approximately 3200 miles should be fair, then becoming poor on
12/13, then back to fair on 12/14.
Equatorial region to Southern Hemisphere "high latitude" propagation conditions
in excess of 3200 miles should be poor, then becoming fair on 12/13, then back
to fair on 12/14.
Propagation Forecast Scales-
Excellent- +1 db Over S9 Or better
Good- S7-9
Fair- S4-6
Poor- S1-3
GLOBAL NOISE (QRN) OUTLOOK-
U.S. LIGHTNING STRIKE DATA
(See Where Your QRN Is Coming From)
Sorry but global views of near real time lightning strikes are no longer
available.
http://www.lightningstorm.com/tux/jsp/gpg/lex1/mapdisplay_fre.sp;jsessionid=70301187101071113657379
During the 7 day outlook period there will be "moderate 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 cyclones.
Northern hemisphere mid latitude regions can expect "moderate to high"
lightning induced QRN tied to winter season thunderstorms, cold/warm/occluded
fronts, associated extra-tropical cold core low pressure systems and El Nino.
Northern hemisphere high latitude regions can expect "low" lightning induced
QRN tied to winter season thunderstorms, cold/warm/occluded fronts and
associated extra-tropical cold core low pressure systems.
During the outlook period there will be "high" 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 cyclones.
Southern hemisphere mid latitude regions can expect "high" lightning induced
QRN, tied to summer season thunderstorms and tropical cyclones.
Southern hemisphere high latitude regions can expect "moderate" lightning
induced QRN tied to summer season thunderstorms, cold/warm/occluded fronts and
associated extra-tropical cold core low pressure systems.
END OF FORECAST
SOLAR, SPACE WEATHER AND GEOMAGNETIC INDICES FOR 12/03-09/2004-
Sunspot Groups- No sunspot group #'s contained twisted magnetic signatures
capable of producing large M class or larger solar flares.
Solar Flux Readings- 81 to 101
SEC Sunspot Number- 26 to 58
Solar Wind Speed- 289-553
X-Ray Solar Flares- C-2 M-0 X-0
Averaged Daily Background X-Ray Flux- A9.2-B1.7
Elevated Energetic Protons >10 MeV (10+o)- 1
Geo or partially geoeffective (Earth Facing) Coronal Mass Ejections- 1
One full halo geoeffective (Earth Facing) Coronal Mass Ejection (CME) occurred
during the period. It occurred on 12/08/04 in association with a C2.5 solar
flare and 20 deg. filament eruption.
Recurrent Coronal Hole #131 which became geoeffective beginning on 12/04-05/04,
finally lost it's negative impact on Earth's magnetic field on UTC 12/09/04. It
produced a max Kp of 5 and a max Ap of 39.
Minor polar cap absorption on high latitude propagation paths due to excessive
energetic protons >10 Mev (10+0) occurred.
The Ap index has been at quiet to minor storm levels, with a range of 0 to 39.
The Kp index has been at quiet to minor storm levels, with a range of 0 to 5.
Here are some "general" guidelines concerning correlation of propagation
indices to actual expected HF/MF propagation conditions.
1.) Dropping indices numbers are better, with the exception of solar flux and
sunspot number on HF.
2.) For medium frequencies a solar flux under 150, under 100 better, 70 is best
for E layer multi hop. For high frequencies over 125 is good, over 150 is
better, over 200 is best.
Keep in mind though that at medium frequencies the 10.7 cm (2800 mhz) solar
flux index is not a "reliable" gauge of ionization in our atmosphere, 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.
3.) Solar flux of at least 100 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) for 160/120 meters and no
greater then (10-1) on MF AM broadcast band.
7.) Background x-ray flux levels less than C1 for several days consecutively
for 160/120 meters and less then B9 for MF broadcast band but A9 or less is
best.
8.) No current STRATWARM alert.
9.) IMF Bz with a (+) sign, indicates a lesser chance of high latitude path
auroral absorption/unpredictable refraction or scattering of MF 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.
TODAY'S PROPAGATION LESSON -
Aurora Oval Blockage, Absorption And Refraction-
The aurora ovals "generally" have a negative impact on medium-frequency
propagation. If the path over which you are communicating lies along or inside
one of the Aurora Ovals, you will experience degraded propagation in one of
several different forms; strong signal absorption, brief periods of strong
signal enhancement, which is mainly caused by tilts in the ionosphere that
allow signals to become focused at your location or very erratic signal
behavior in the form of strong and rapid fading, etc., caused by a variety of
effects such as multi-pathing, anomalous and rapid variations in absorption,
non-great-circle propagation, horizontal or side refraction and/or scatter
(skewing) due to changes in electron density and polarization changes.
When the Aurora Oval zones are contracted and latitudinally-thin coinciding
with low geomagnetic activity, it is possible for a medium-frequency
transmitted signal to propagate through the Aurora Oval zone without being
heavily absorbed by skirting underneath it.
During periods of very low geomagnetic activity, areas of the Aurora Oval zones
may only have a latitudinal thickness of approximately 300 miles. But radio
signals reflected from the E-layer can travel over distances of as much as 300
to 1250 miles at heights below the ionosphere for low take-off angles of
between 10 and 25 degrees. When the geometry is just right, the
medium-frequency transmitted signal can literally propagate underneath and
through the Aurora Oval zones into the polar ionosphere which is less disturbed
and from the polar ionosphere back into the middle latitude ionosphere, without
ever coming in contact with the highly absorptive Aurora Ionosphere. This type
of propagation is not as rare as you might think and it can provide unusually
stable polar region path openings to (TA) Transatlantic and (TP) Transpacific
regions. But because the Aurora Oval zone expands and contracts constantly,
such conditions often do not last very long.
For more information go to KN4LF HF/MF Frequency Radio Propagation Theory Notes
at http://www.kn4lf.com/kn4lf8.htm
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
Standard Disclaimer-
Note! I use "RAW" public domain data from the NOAA Space Environment Center, as
well as other U.S. government organizations, to produce my "not for profit"
propagation forecast outlooks. This data is gathered and made public by the
U.S. Government using taxpayer $$$. However the forecast outlooks that I
produce from the "RAW" public domain data, is my personal intellectual
property. Therefore the propagation outlooks contained herein is copyrighted ©
1988-2004 by Thomas F. Giella and the Florida Space and Atmospheric Weather
Institute, all rights reserved. Reproduction of information herein is allowed
as long as proper credit is given.
Also space weather forecasting is still an inexact science. The discussions,
forecasts and outlooks are not official but for educational purposes only and
are subject to human error and acts of God, therefore no guarantee or warranty
implied.
73 & GUD DX,
Thomas F. Giella, KN4LF
Retired Space & Atmospheric Weather Forecaster
Plant City, FL, USA
Grid Square EL87WX
Lat & Long 27 58 33.6397 N 82 09 52.4052 W
kn4lf@arrl.net
Propagation eGroup: http://lists.contesting.com/mailman/listinfo/propagation
PropNET Beacon Program: http://www.propnet.org
KN4LF Daily Solar Space Weather & Geomagnetic Data Archive:
http://www.kn4lf.com/kn4lf5.htm
KN4LF HF/MF Frequency Radio Propagation Theory Notes:
http://www.kn4lf.com/kn4lf8.htm
KN4LF Amateur & SWL Radio History: http://www.kn4lf.com/index.htm
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