Just an FYI! I have begun producing a daily (MF) medium frequency radio wave
propagation forecast in unison with the HF one. The MF forecast follows the
HF forecast.
Greetings to my fellow hamateur radio and SWL radio enthusiasts around the
world.
Welcome to my “not for profit” daily W4HM Daily HF/MF Radio Wave Propagation
Forecast.
It’s the only daily global HF/MF radio wave propagation forecast produced on
the planet.
I'm a retired heliophysicist, terrestrial/troposphere
meteorologist/climatologist, physical oceanographer and one of the few on
the planet with advanced education and forecast experience in all
aforementioned disciplines. In terrestrial/troposphere weather forecasting I
have 45 years of experience and in solar, space and geomagnetic weather
forecasting 34 years.
This is created and disseminated by Thomas F. Giella, W4HM in Lakeland, FL,
USA © 1988-2018.
If you find this daily HF/MF radio wave propagation forecast useful to your
hamateur and SWL radio activities, feel free to drop me a line and let me
know that at
thomasfgiella@gmail.com
I enjoy hearing from likeminded fellow radio enthusiasts.
Hams and SWLs that are interested in solar, space & geomagnetic weather as
well as radio wave propagation are a special group of people interested in
broadening their knowledge in science.
Feel free without prior permission to redistribute this daily HF/MF radio
wave
propagation forecast, as long as you redistribute it in its entirety and
give me credit for it.
Supporting images associated with this daily HF/MF radio wave propagation
forecast can be found in my Facebook account at
https://www.facebook.com/thomasfranklingiellaw4hm
and in my Twitter account at
https://twitter.com/GiellaW4hm
Last but not least here is my new HF/MF radio wave propagation web page
where you can sign up to receive this daily HF/MF radio wave propagation
forecast via email.
It's a NO SPAM voluntary "opt" in email type group hosted by Groups.io, so
you have to sign up by using an existing email address and creating a
password.
https://groups.io/g/w4hmradiowavepropagationforecast
>>>>>W4HM Solar Cycle 24 Update and Solar Cycle 25 Forecast- Short and to
>>>>>the point.
Solar minimum may begin later this year and may last longer than any
previous solar cycle in the 20th century. When solar cycle 25 finally gets
underway it could be the weakest since the middle of the 19th century.
Another Dalton type lesser grand solar minimum may occur with a
corresponding cooling of earth’s climate. This would negate anthropogenic
climate change if it were occurring which it isn’t.
On February 1, 2008 I forecasted that solar cycle 24 would be the smallest
solar cycle in the past 100 years. That forecast verified. I also forecasted
that solar cycle 25 would be almost non nonexistent.<<<<<
#342 Issued Friday December 7, 2018 at 1545 UTC
Important Solar, Space & Geomagnetic Weather Indices-
Solar activity was very low.
The daily solar flux index numbers (DSFI) were
70.2 69.7 69.6.
There had been 20 consecutive days with a 2000 UTC daily solar flux index
number (SFI) below 70.
The official daily sunspot number (DSSN) was 17.
There had been 2 consecutive days with an official daily sunspot number
(SSN) above 0.
In 2018 prior to the above event there had been 203 days with an official
daily sunspot number (DSSN) of 0.
There had been one sunspot group numbered 12729 located near S05W52 with a
relatively simple beta magnetic signature capable of releasing an isolated
small C class solar flare.
The 24 hour period 3 hour interval planetary K index (Kp) had been at a
quiet geomagnetic condition of
2 2 1 1 2 1 1 1.
The 24 hour period planetary A index (Ap) maximum and minimum values ranged
between
7 & 4,
which had been at a quiet geomagnetic condition.
The 24 hour period maximum and minimum Disturbance Storm Time Index (Dst)
ranged between
-13 & +14 nT.
The 24 hour period maximum and minimum solar wind speed was 381 & 347 km/s.
Global Daily HF/MF Radio Wave Propagation Forecast-
HF/MF radio wave propagation condition “trend” on Dec 7, 2018- steady.
HF/MF radio wave propagation condition “trend” on Dec 8, 2018- minor
deterioration.
HF/MF radio wave propagation condition “trend” on Dec 9, 2018- steady.
Northern Hemisphere Radio Wave Propagation Forecast g-
3150-3400, 3500-4100, 4750-5050, 5700-6300 kHz- S9 +1 to 9 at night and S1-3
at day,
6900-7800, 9200-9995, 10000-10150, 11500-12200 kHz- S9+ 1 to 9 at night and
S4-7 at day,
13570-13850, 14000-14350, 15005-15900, 17450-17950, 18068-18168 kHz- S0 at
night and S3-4 at day,
21000-21850 kHz- S0 at night and S1-2 at day,
24890-24990, 25600-26100 kHz- S0 at night and S1 at day,
28000-29700 kHz- S0 at night and S0 at day.
We are now in the fall/spring equinox type of HF radio wave propagation
conditions. Globally HF radio wave propagation conditions are most evenly
balanced across the equator during the fall and spring equinox.
Southern Hemisphere Radio Wave Propagation Forecast g-
3150-3400, 3500-4100, 4750-5050, 5700-6300 kHz- S9 +1 to 9 at night and S1-3
at day,
6900-7800, 9200-9995, 10000-10150, 11500-12200 kHz- S9+ 1 to 9 at night and
S4-7 at day,
13570-13850, 14000-14350, 15005-15900, 17450-17950, 18068-18168 kHz- S0 at
night and S3-4 at day,
21000-21850 kHz- S0 at night and S1-2 at day,
24890-24990, 25600-26100 kHz- S0 at night and S1 at day,
28000-29700 kHz- S0 at night and S0 at day.
We are now in the fall/spring equinox type of HF radio wave propagation
conditions. Globally HF radio wave propagation conditions are most evenly
balanced across the equator during the fall and spring equinox.
GLOBAL (MF) MEDIUM FREQUENCY (300-3000 KHZ) RADIO WAVE PROPAGATION
CONDITIONS EXPECTED-
FORECASTED NORTHERN HEMISPHERE SHORT PATH-
-East <-> West To 1100 Mi /1800 km S9
*North <-> South To 1100 Mi /1800 km S7-9
+South <-> North To 1100 Mi /1800 km S5-7
FORECASTED SOUTHERN HEMISPHERE SHORT PATH-
-East <-> West To 1100 Mi / 1800 km S9
*South <-> North To 1100 Mi /1800 km S7-9
+North <-> South To 1100 Mi / 1800 km S5-7
FORECASTED GREAT CIRCLE LONG OR SKEWED PATH-
Northern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans
Pacific and cross Equatorial propagation conditions in excess of
approximately 3200 mi / 5200 km-
High Latitude S4-6
Mid Latitude S4-6
Low latitude S5-7
FORECASTED GREAT CIRCLE LONG OR SKEWED PATH-
Southern Hemisphere (TA) Trans Atlantic, (TI) Trans Indian, (TP) Trans
Pacific and cross Equatorial propagation conditions in excess of
approximately 3200 mi / 5200 km-
High Latitude S4-6
Mid Latitude S7-9
Low latitude S5-7
We are now in the fall/spring equinox type of MF radio wave propagation
conditions. Globally MF radio wave propagation conditions are most evenly
balanced across the equator during the fall and spring equinox.
Medium frequency (300-3000 khz) radio wave 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 energetic electron flux levels at energies greater than 2 MeV (2+1),
geomagnetic disturbances (Kp-3-4) and geomagnetic storms (Kp-5 & >) that
increase signal absorption via the E layer (the general 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 greater
than A0, proton flux levels at energies greater than 10 MeV (10+0), hard
x-rays and galactic cosmic rays.
There is also the issue of magneto ionic power coupling. Antenna
polarization plays a large role in the success of a long haul MF DX contact.
As a MF RF signal traverses Earth's magnetic lines of force in a
perpendicular manner on high and mid latitude paths say between W3 land and
SM, higher angle horizontally polarized signals are more readily absorbed
than lower angle vertically polarized signals. On other propagation paths on
the globe opposite results can be found, i.e., horizontally polarized
signals suffer less absorption on a propagation path between VK6 and W6 or
S9 and W4.
Unfortunately the simplest way to look at medium frequencies with respect to
radio wave propagation conditions is to accept the fact that propagation is
poor the majority of the time, especially past approximately 1250 miles (one
maximum distance refraction off of the E layer), with occasional short-lived
good periods as far as 3200 miles.
All 13 of the following indices have to occur as described below in order to
see the best global medium frequency (MF) radio wave propagation possible.
The simplest way to look at medium frequencies (MF) with respect to radio
wave propagation conditions is to accept the fact that propagation is poor
the majority of the time, especially past approximately 1250 miles (one
refraction off of the E layer), with occasional short-lived good periods as
far as 3200 miles.
1.) Dropping geomagnetic field indices numbers are better, Kp of 0 best.
2.) A daily sunspot number under 100, under 70 best.
3.) A daily sunspot number no higher then the 100 for routine stable
formation of the E Valley/F Layer ducting mechanism.
4.) Previous 24 hour Ap index under 10, fewer than 7 for several days
consecutively are best.
5.) Previous 3 hours Kp index fewer than 3 for mid latitude paths, fewer
than 2 for high latitude paths, 0 for several days consecutively is best.
6.) Energetic proton flux levels no greater than 10 MeV (10+0).
7.) Background x-ray flux levels of A0 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 aurora
absorption/unpredictable refraction or scattering of medium frequency RF
signals, when the Kp is above 3.
10.) A -10 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.
11.) Galactic cosmic rays decrease to -3 units below zero and trending
towards zero.
12.) Energetic electron flux levels no greater than 2 MeV (2+0).
13. A solar wind speed of less than 300 km/s for several days consecutively.
THE FOLLOWING INFORMATION IS EDUCATIONAL MATERIAL ON SOLAR SPACE,
GEOMAGNETIC WEATHER OBSERVING AND FORECASTING AS WELL AS GOINGS ON IN EARTH’S
IONOSPHERE.
This HF/MF Radio wave propagation forecast is produced based on the
SIGINT_CAP HF/MF radio wave propagation prediction software. I wrote it
beginning in the late 1980’s but I’m sorry to say that it can’t be
distributed to the general public. It does outperform VOA CAP.
And though this HF radio wave propagation forecast is produced based on the
SIGINT_CAP software, I do check the actual band conditions at my location in
the USA and tweak the forecast manually where and when necessary.
I also check global HF radio wave propagation conditions via remoted radio
receivers on every continent of the globe and tweak the forecast manually if
and when necessary.
And last but not least I look at ionsonde stations on every continent of the
globe.
The hamateur radio JT65A mode RF signal levels received are based on 5 watts
and ½ wave dipole up at 40 feet.
The hamateur radio PSK31 mode RF signal levels received are based on 25
watts and ½ wave dipole up at 40 feet.
The hamateur radio CW mode RF signal levels received are based on 50 watts
and ½ wave dipole up at 40 feet.
The hamateur radio SSB RF mode signal levels received are based on 100 watts
and ½ wave dipole up at 40 feet.
The HF shortwave broadcast band AM Mode RF signal levels are based on
100,000 watts (100 kw) and a typical high gain VOA type curtain array
antenna.
The MF shortwave broadcast band AM Mode RF signal levels are based on
50,000 watts (50 kw) and an omnidirectional vertical antenna.
Please keep in mind that this is a relatively simplified HF/MF radio wave
propagation forecast, so as to keep it easily understandable and applicable
by the average radio enthusiast.
Globally HF/MF radio wave propagation conditions are most evenly balanced
during the fall and spring equinoxes and most diametrically opposed during
the summer and winter solstices.
Conditions change daily, weekly, monthly, yearly and by decade, as the
sun rises and sets at different times and at different angles from the
ecliptic, as well as by radio wave frequency. This is due to changes in the
maximum usable frequency (MUF), lowest usable frequency (LUF) and F layer
critical frequency (FoF2). Also by propagation path.
The D and E layers also come into play through RF radio wave signal
absorption and refraction. And then there is sporadic E (Es) radio wave
propagation that can really throw a wrench into the gears so to speak.
Things like sporadic E (Es) radio wave propagation and lightning storm
static can impact HF radio wave propagation in an unpredictable manner and
mostly bad.
Ongoing solar, space and geomagnetic weather goings on also impact HF radio
wave propagation conditions in a negative manner.
Lower high frequency (80-30 meters) propagation conditions are impacted in a
negative manner not so much by variations in the maximum usable frequency
(MUF) along a particular propagation path and time but rather due to
geomagnetic elevated geomagnetic conditions (Kp-3-4), storms (Kp-5 &
greater) 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 RF signal absorption due to hard x-rays, galactic cosmic waves,
elevated background solar flux levels greater than B0 and energetic 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 elevated geomagnetic conditions (Kp-3-4), storms of Kp-5 &
greater. Also D layer RF signal absorption due to elevated (greater than B0)
background solar flux levels. Also to a lesser extent elevated proton flux
at energies greater than 10 MeV (10+0).
GENERAL GUIDELINES CONCERNING CORRELATION OF PROPAGATION INDICES TO ACTUAL
HF PROPAGATION CONDITIONS-
NOTE!!! The propagation indices "interpretations" are my personal
intellectual property. Therefore the HF radio wave propagation indices
interpretations contained herein is copyrighted © 1988-2018 by Thomas F.
Giella, W4HM, all rights reserved. Reproduction of information herein is
allowed without permission in advance as long as proper credit is given.
All 14 of the following indices have to occur as described below in order to
see the best global high frequency (HF) radio wave propagation possible,
something that happens only rarely.
1.) Dropping geomagnetic field indices numbers are better, Kp of 0 best.
2.) A daily sunspot number of 150 or higher, 200 or higher best.
3.) A daily sunspot number of greater than 100 for routine stable formation
of the E Valley/F Layer ducting mechanism.
4.) Previous 24 hour Ap index under 10, fewer than 7 for several days
consecutively are best.
5.) Previous 3 hours Kp index fewer than 3 for mid latitude paths, fewer
than 2 for high latitude paths, 0 for several days consecutively is best.
6.) Energetic protons no greater than 10 MeV (10+0).
7.) Background x-ray flux levels greater than B1 for several days
consecutively, greater than C1 best.
8.) No current STRATWARM alert.
9.) Interplanetary magnetic field (IMF) Bz with a (positive number) sign,
indicates a lesser chance of high latitude path aurora
absorption/unpredictable refraction or scattering of medium frequency RF
signals, when the Kp is above 3.
10.) A -10 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, other U.S. government entities and educational
institutions, to produce this daily HF/MF radio wave propagation
forecast. This data is gathered and made public by the U.S. Government using
taxpayer $$$ (including mine).
However this daily HF/MF propagation forecast that I produce from the RAW
public domain data is my personal intellectual property. Therefore this
daily HF/MF radio wave propagation forecast contained herein is copyrighted
©
1988-2018 by Thomas F. Giella, W4HM.
Feel free without prior permission to redistribute this daily HF/MF radio
wave
propagation forecast, as long as you redistribute it in its entirety and
give me credit for it.
Also HF/MF radio wave propagation forecasting is still an inexact
science and therefore also an art. The forecasts are not official but for
educational and hobby related purposes only and are subject to human error
and acts of God, therefore no guarantee or warranty implied.
