[SFDXA] W4HM Daily HF-MF Radio Wave Propagation Forecast 2019-24

[Bill]

*#24 issued Wednesday January 24, 2019 at 1630 UTC*

**

*Important Solar, Space & Geomagnetic Weather Indices-*

**

*Solar activity was very low. *

**

*The daily solar flux index numbers (DSFI) were *

**

*72.7 71.5 72.9.*

**

*There had been 3 consecutive days with a 2000 UTC daily solar flux 
index number (SFI) of 70 or above.*

**

*Unfortunately daily SFI numbers in the 70’s doesn’t increase ionization 
via ultraviolet light striking the F2 layer, to raise the maximum usable 
frequency (MUF) high enough to activate the 15, 12 and 10 meter bands 
along east-west radio wave propagation paths.*

**

*The official daily sunspot number (DSSN) was 18.*

**

*There had been 3 consecutive days with an official daily sunspot number 
(DSSN) above 0.*

**

*In 2019 there had been 15 days with an official daily sunspot number 
(DSSN) of 0.*

**

*In 2018 there had been 222 days with an official daily sunspot number 
(DSSN) of 0.*

**

*There had been no earth facing sunspot group.*

**

*There had been one sunspot group numbered 12733 located near N06E08 
with a relatively complex beta magnetic signature capable of releasing a 
very small A and B class solar flare and an isolated small C class solar 
flare. *

**

*The 24 hour period 3 hour interval planetary K index (Kp) had been at 
an active to quiet geomagnetic condition of***

**

*3 2 4 4 3 4 2 1.*

**

*The 24 hour period planetary A index (Ap) maximum and minimum values 
ranged between *

**

*6 & 0, *

**

*which had been at a quiet geomagnetic condition.*

**

*The 24 hour period maximum and minimum Disturbance Storm Time Index 
(Dst) ranged between *

**

*-18 & +17 nT.*

**

*The 24 hour period maximum and minimum solar wind speed was *

**

*332 & 284 km/s.*

**

*No Earth directed (geoeffective) Coronal Mass Ejection (CME) was 
observed in available coronagraph imagery.*

**

*No Earth directed (geoeffective) Coronal Hole (CH) was observed in 
available coronagraph imagery.*

**

**

*GLOBAL (HF) HIGH FREQUENCY (3000-30000 KHZ) RADIO WAVE PROPAGATION 
CONDITIONS EXPECTED-***

**

*HF-MF radio wave propagation condition “trend” on Jan 24, 2019- minor 
deterioration.*

**

*HF-MF radio wave propagation condition “trend” on Jan 25, 2019- improving.*

**

*HF-MF radio wave propagation condition “trend” on Jan 26, 2019- steady.*

**

*Northern Hemisphere HF Radio Wave Propagation Forecast *g*-*

**

*We are now in the winter season northern hemisphere HF-MF radio wave 
propagation season. *

*The approximate 11000- 30000 kHz frequency range closes sooner due to 
less sun light illuminating**the ionosphere than in the southern 
hemisphere. But the maximum usable frequency (MUF) is higher than in the 
southern hemisphere as the F layer of the ionosphere is lower in height 
and the ions more concentrated.*

*The approximately 3000-10000 kHz frequency range often stays open for 
DX all throughout the day due to a weaker D and E layer and therefore 
less RF signal absorption.***

*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.*

**

*Southern Hemisphere HF Radio Wave Propagation Forecast *g*-*

**

*We are now in the summer season southern hemisphere HF-MF radio wave 
propagation season.*

**

*The 14000- 30000 kHz frequency range closes later due to more sun light 
illuminating the ionosphere than in the southern hemisphere. But the 
maximum usable frequency (MUF) is lower than in the southern hemisphere 
as heating in the F2 layer of the ionosphere is higher and the layer 
ions less concentrated.*

**

*Almost d**aily during the northern hemisphere summer season you will 
find that the 25600- 26100 kHz and 28000-29700 kHz frequency ranges will 
open via short north-south and east-west propagation paths via sporadic 
E (Es). Also when multiple sporadic E (Es) clouds form and line up 
favorably much longer propagation paths open up on east-west paths. And 
last but not least north-south propagation paths occur across the 
equator via trans equatorial propagation (TEP).*

**

*3150-3400, 3500-4100, 4750-5050, 5700-6300 kHz- S9+10 at night and S3-5 
at day,

6900-7800, 9200-9995, 10000-10150, 11500-12200 kHz- S9+15 at night and
S4-7 at day,

13570-13850, 14000-14350, 15005-15900, 17450-17950, 18068-18168 kHz- 
S1-3 at night and S5-8 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.*

**

**

*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-+1*

**North <-> South To 1100 Mi /1800 km*

	

*S5-6*

*+South <-> North To 1100 Mi /1800 km*

	

*S7-8*

*
**FORECASTED SOUTHERN HEMISPHERE SHORT PATH-*

*-East <-> West To 1100 Mi / 1800 km*

	

*S9*

**South <-> North To 1100 Mi /1800 km*

	

*S5-6*

*+North <-> South To 1100 Mi / 1800 km*

	

*S7-8*

*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*

	

*S9*

*Low latitude*

	

*S7-8*

**

*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*

	

*S2-4*

*Mid Latitude*

	

*S6-7*

*Low latitude*

	

*S3-5*

**

*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 
still can’t be distributed to the general public. It does outperform VOA 
CAP and Prop Lab.*

*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-MF 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 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.*

**

*THE FOLLOWING IS EDUCATIONAL MATERIAL ON SOLAR, SPACE, GEOMAGNETIC 
WEATHER OBSERVING AND IONOSPHERE GOINGS ON. ALSO HF AND MF RADIO WAVE 
PROPAGATION CONDITIONS AND FORECASTING.*

*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.*

**

*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-MF radio wave propagation indices*

*interpretations contained herein is copyrighted © 1988-2019 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.*

**

*GENERAL GUIDELINES CONCERNING CORRELATION OF PROPAGATION INDICES TO 
ACTUAL MF PROPAGATION CONDITIONS-*

**

*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.

***

**

*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 ©*

*1988-2019 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.*

**