2001 KN4LF 7 Day Medium Wave Radio Propagation Outlook Archive

2001
KN4LF 7 DAY
MEDIUM WAVE RADIO PROPAGATION OUTLOOK ARCHIVE

(SEC) SPACE ENVIRONMENT CENTER TERMINOLOGY AND DEFINITIONS GLOSSARY
SEC SPACE WEATHER MAGNETIC CLASS TERMINOLOGY AND DEFINITIONS
SEC SPACE WEATHER SOLAR FLARE TERMINOLOGY AND DEFINITIONS

Welcome to the 2001 KN4LF 7 Day Medium Wave Radio Propagation Outlook. This site is non profit, educational and information oriented, with the intention of helping my fellow radio brethren and especially those interested in understanding radio wave propagation on the AM broadcast band and 160 meters and using the information to further their DXing efforts.

I will likely add and subtract a variety of information until I'm satisfied with the end product. I will try to keep things in simple to understand layman terms, as long complicated technical explanations can be boring and make one's eyes glaze over. Unfortunately though sometimes while trying to keep things simple certain definitions, meanings and technical aspects can get watered down or even lost, which tends to open me up criticism from well meaning individuals who just don't understand the KISS principle. The propagation outlooks are totally mine and derived from raw data, no plagerism or looking at what the government boys are saying, just like my weather forecasts during the past 28+ years.

KN4LF MEDIUM WAVE RADIO PROPAGATION THEORY NOTES

Outlook #2001-3A Published 10:00 AM EST 12/18/01

As ionosphere expert Dr. Robert Brown NM7M noted on the 160 meter Topband Reflector yesterday we are seeing less geomagnetic activity recently tied to the approaching winter solstice. The effects of the solar wind on the magnetosphere decrease as we approach the solstices. Why? basically it's the orientation of Earth's magnetic field with respect to the interplanetary magnetic field within the solar wind. When solar material and shock waves reach Earth their effects may be enhanced or dampened depending on the angle at which they arrive.

Most sunspot groups appear stable and quiet except for newly arrived #9742 which is growing and poses the best threat for a large solar flare in future days.

As 160 meter Amateur Radio Operators and AM Broadcast Band DX'ers have noticed in the past few days, some TA and TP DX has finally been showing up again. Why? No coincidence, as the proton flux level has been at 10o to-1 AND the background X-ray flux has been below C3. See two links below.

Click For X-Ray Flux For 12/15-16/01

Click For X-Ray Flux For 12/16-18/01

My forecast for proton flux level and geomagnetic activity following the X 6.2 class solar flare was elevated K indicies of 3-4 and also an elevated proton flux level of at least 10 +1/2, beginning on Saturday 12/15/01 and lasting through the weekend.

The actual result was an elevated K index of 3-4 and an elevated proton flux level of slightly above 10o, beginning on Saturday 12/15/01.

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Outlook #2001-3 Published 4:00 PM EST 12/14/01 For 12/15/01-12/21/01

Sunspot region 9727 is basically unchanged with a magnetic delta structure and remains capable of producing an X class flare but fortunately it will rotate over the western limb on Saturday 12/15/01. Sunspot region 9733 has changed a lot in appearance during the past 48 hours, particularly after the major X 6.2 solar flare. The magnetic delta structure has disappeared. It currently carries a magnetic beta gamma structure and is capable of an M5 class flare.

New sunspot groups are emerging in several places and further development is likely. New sunspot region 9739 emerged in the southern hemisphere over the central meridian and appears to be slowly developing, with a magnetic beta signature. New region 9740 emerged near the southeast limb, with a magnetic alpha signature. New region 9741 rotated into view at the northeast limb, with a magnetic alpha signature.

The proton flux level has been below 10o (10 MeV) to as low as 10-1 for approximately 2 days now and this should lead to some good domestic propagation within approximately 1100 miles and at times out to 3000 miles. However solar flux values continue in the 200-225 range and this will lead to some added absorption of signals not normally seen at the low part of the approximate 11 year sun spot cycle.

The X 6.2 level solar flare event on 12/13/01, ejected a coronal mass ejection (CME) that was not completely Earth directed but never the less I do expect an elevated K index of 3-4 and an elevated proton flux level of at least 10 +1/2 beginning on Saturday 12/15/01 and lasting through the weekend. Unlike HF frequencies small changes in D layer absorption has a big impact on the medium wave band, possibly including C class solar flares.

I place the likelihood of an M 1-4 class solar flare at 100%, an M5 class or higher solar flare at 70% and X1 class or higher solar flare at 40% during the upcoming 7 day outlook period.

The bottom line for the next 7 days? Fairly decent stateside propagation, with high latitude (TA) Trans Atlantic and (TP) Trans Pacific propagation on the broadcast band and 160 meters poor to marginal, with occasional openings. There will also be some occasional lightning induced QRN across North America also, with a series of approaching cold fronts and surface extra-tropical low pressure systems. Most stateside AM broadcast band frequencies will contain co-channel North and Central/South American stations, with either dominating at times. Remember though, an M 5 class solar flare or stronger and conditions turn auroral real quick.

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Outlook #2001-2C Published 10:00 AM 12/14/01

It appears that the X 2.8 class solar flare eruption on 12/11/01 has had a minimal impact on our ionosphere, as it was not completely Earth directed, on so to speak. We did have a brief period with the Boulder K index moving into the 4-5 range whci is active to minor storm and the proton flux also briefly was elevated past 10o (10 MeV).

Yesterday's solar flare event reached an X 6.2 level, VERY BIG but once again the CME was not completely Earth directed but never the less I do expect elevated K indicies above 5 and also elevated proton flux levels of at least 10 +1 to 2 beginning on Saturday. Unlike HF frequencies small changes in D layer absorption has a big impact on the medium wave band.

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Outlook #2001-2B Published 9:40 AM 12/13/01

BANG AGAIN!!! At 1425 UTC a large approximate X 6.2 Solar flare occurred and originated from sunspot groupf #9737. How did I know it occurred? I was listening to a SW broadcast station on 13 meters, when the station abruptly disappeared! This X class flare is probably more earth directed then the last one and doesn't bode well for MW propagation in the next few days.

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Outlook #2001-2A Published 3:00 PM EST 12/11/01

BANG!!! Per our 7 day outlook, twisted magnetic fields in association with sunspot group #9733 erupted today at 0805 UTC. The explosion created an X 2.8-class solar flare which has initiated a strong radio blackout across Europe and much of Asia. As the proton flux has only inched up to near 10o (10 MeV) as of 2000 UTC, it's unclear at this time just how much of an impact the CME will have. Stay tuned, though as high latitude propagation path absorption should increase in some form tonight and during the next 24 hours, peaking by Friday 12/14/01.

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Outlook #2001-2 Published 4:00 PM EST 12/06/01 For 12/08/01-12/14/01

The proton flux level has been below 10o (10 MeV) to as low as 10-1 for approximately 5 days and this should lead to some good domestic, high latitude (TA) Trans Atlantic and (TP) Trans Pacific propagation for the ARRL 160 meter contest and also on the broadcast band. Also as an added bonus, lightning induced QRN should be at reasonably low levels across North America, though the deep south could experience periods of elevated QRN with an approaching cold front.

Alas though, the solar flux is above 247 and this will lead to some added absorption of signals not normally seen at the low part of the approximate 11 year sun spot cycle.

Sunspot 9727 has developed a delta-class magnetic field and poses a threat for an X-class solar flare or two. Meanwhile sun spots 9715 and 9718 have beta-gamma magnetic fields that contain energy for M-class flares. An earthward bound M7 or higher class solar flare will initiate high latitude propagation path absorption.

I place the likelihood of an M 5 class or higher solar flare at 80% and and X1 class or higher solar flare at 40% during the 7 day period.

The bottom line for the next 7 days? No substantial solar flares and high latitude path medium wave conditions continue to improve. However we cannot expect really good openings with the present high solar flux levels. M7 class solar flare or stronger and conditions are back to where they have been most of this DX season so far, lousy.

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Outlook #2001-1A Published 4:00 PM EST 12/03/01

The proton flux level has been below 10o (10 MeV) to as low as 10-1 for approximately 48 hours and this should lead to some of the best domestic, (TA) Trans Atlantic and (TP) Trans Pacific propagation on the broadcast band and 160 meters in quite some time tonight. Alas though, the solar flux is above 230 and this will lead to some added absorption of signals, especially below approximately 1100 kc.

Sunspot regions 9715, 9717 and 9718 have beta-gamma magnetic fields that contain energy for M 5 class flares or higher. The peak daily solar flux so far this 7 day forecast period has been 249.

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Outlook #2001-1 Published 12:00 PM EST 12/01/01, For 12/01/01-12/07/01

Solar activity is high. The approximate 28 day cyclical solar flux minimum was 170 on 11/25/01. Today it's 221 and rising. The past three solar flux peaks were 271 on 11/09/01, 263 on 10/19/01 and 285 on 09/28/01. The next 28 day cyclical solar flux peak may exceed 250 or even reach 270.

High solar flux values are generally considered to be detrimental to medium wave signals both domestic and TA/TP, as more absorption can be present via the transmitted signals two trips through the D layer, near sunrise and sunset. However even with a solar flux in excess of 200 I have personally been hearing WSM 650 kc Nasheville, TN. as well as skywave signals on 160 meters here in Central Florida during local high noon the past couple of days, through the D layer at it's height of ionization, so it's not a hard fast rule. Most long haul medium wave DX signals in excess of 3000 miles is via the E/F layer ducting and/or E valley propagation modes. Therefore high solar flux values can aid in long haul medium wave propagation paths in excess of 3000 miles, as a high solar flux value ensures a strong E and F layer duct mechanism.

Sunspot regions 9715, 9718 and 9720 have the potential for producing M-class flares, via CME's (coronal mass ejections). M5 class solar flares and above have the energy to produce visible aurora and elevated proton flux levels in excess of 10 MeV, a level capable of absorbing high latitude medium wave signals and creating what we normally call auroral conditions, when signals from a southerly direction are co-channel with or dominant over northerly direction signals.

Region 9715 has good potential to produce an X-class solar flare or two. X class solar flares have the ability to create visible aurora south of 30 degrees north latitude and north of 30 degrees south latitude, polar radio blackouts, polar cap absorption, high and mid latitude absorption via D layer overionization and ionospheric storms. X class solar flares can produce a lingering negative effect on high latitude medium wave propagation paths, long after all elevated events are over and the A and K indices return to normal. I don't pay much attention to the A and K indices as they don't correlate very well with medium wave propagation conditions. The key is the proton flux level above 10o (10 MeV). The higher the proton mev level the higher the frequency absorbed.

I place the likelihood of an M 5 class or higher solar flare at 90% and and X1 class or higher solar flare at 50% during the 7 day period.

The bottom line for the next 7 days? No substantial solar flares and high latitude path medium wave conditions continue to improve. M7 class solar flare or stronger and conditions are back to where they have been all season so far, lousy!

As the proton flux drops below 10o (10 MeV) expect improved domestic east west propagation and improved TA and TP propagation especially on higher frequencies. However there can still be some co-channel signals from the Caribbean, Central and South America, especially on the lower frequencies.

If the proton flux dips well below 10o (10 MeV) for a couple of days and it's doubtful at the moment, expect much improved TA and TP reception.

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Published 12:00 PM EST 12/01/01.

I was operating on 160 meters, as well as listening to the domestic AM broadcast band tonight. Distant signals were much louder tonight, for the first time in a good while, especially from a northerly direction. We are on the verge of normal MW band conditions for TA and TP DX, as the proton flux has inched it's way down to 10o (10 MeV).

I've been watching the proton flux and the A & K indices for a long time and can see a direct correlation between a high proton flux and poor high latitude MW propagation paths, where as the A & K don't as readily correlate.

Unfortunately though the large (6 earth diameters) size and growing sunspot #9715 has developed a beta-gamma-delta magnetic twisted "delta-class" magnetic field that harbors energy for powerful X-class eruptions. This spot is nearing the center of the Sun, so explosions from its vicinity this week will likely be Earth-directed.

It's been a dismal MW DX season so far with one solar flare after another and attendant polar radio blackouts, polar cap absorption, high and mid latitude absorption and ionospheric storms.

NOTE! Space weather forecasting is still an inexact science. The discussions, forecasts and outlooks are not official and are subject to human error and acts of God, therefore no guarantee or warranty implied. This site and all information herein is copyrighted � 2001 by Thomas F. Giella, all rights reserved. Reproduction of information herein is allowed as long as proper credit is given.

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