Topband: W4HM Daily HF Radio Wave Propagation Forecast

[Thomas F. Giella]

I also produce a daily HF radio wave propagation forecast on my Facebook 
page at https://www.facebook.com/thomasfranklingiellaw4hm

For my hamateur radio and SWL friends around the globe:

Feel free to redistribute this "not for profit" solar, space and geomagnetic 
weather discussion and HF radio wave propagation forecast, as long as you 
redistribute it in it's entirety and give me credit for it.

Images associated with this HF radio wave propagation forecast can be found 
at https://www.facebook.com/thomasfranklingiellaw4hm

I have decided to begin posting some of my daily solar, space and 
geomagnetic weather discussions and HF radio wave propagation forecasts in 
my Twitter account at

@GiellaW4hm https://twitter.com/?lang=en .

Of course it will consist of little snippets of what's going on as Twitter 
severely limits tweets as far as content length.

Also feel free to leave a "LIKE" every time you access this discussion and 
forecast as it's the only method I have to gauge the usefulness of it.

Issued on Friday February 17, 2017 at 1300 UTC

Global HF Radio Wave Propagation Forecast

HAMATEUR & SW BROADCAST HF BANDS:

NORTHERN HEMISPHERE RADIO WAVE PROPAGATION-

80-60 (75-60) meters- fair at night and poor at day,

40-30 (41-25) meters- fair at night and fair at day,

20-17 (22-16) meters- very poor at night and fair at day,

15 (13) meters- very poor at night and poor at day,

12-10 (11) meters- very poor at night and very poor at day.

SOUTHERN HEMISPHERE RADIO WAVE PROPAGATION-

80-60 (75-60) meters- poor at night and very poor at day,

40-30 (41-25) meters- fair at night and poor at day,

20-17 (22-16) meters- fair at night and fair at day,

15 (13) meters- poor at night and fair at day,

12-10 (11) meters- very poor at night and very poor at day.

Received RF signal strength scale-

Very Good- +1 over S9  Or Greater
Good- S7-9
Fair- S4-6
Poor- S1-3
Very Poor- S0

Meter Band Equivalents
Ham & SWL
160->   90
80->     75
60->     60
40->     49, 41
30->     31, 25
20->     22, 19
17->    16, 15
15->    13
12,10-> 11

Please keep in mind that this is a relatively simplified HF radio wave 
propagation forecast, so as to keep it easily understandable by the average 
radio enthusiast.

Globally HF 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 also 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).

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.
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Solar Space & Geomagnetic Weather Conditions On

Thursday February 16, 2017-

Solar activity was low.

Earth's magnetic field was unsettled.

The three daily solar flux index (SFI) numbers were 74.6 74.0 74.3.

The official daily sunspot number (SSN) was 11.

Sunspot group #12635 was located near N11E42 with a simple alpha magnetic 
signature.

Newly emerged sunspot group #12636 was located near N15E61 with a simple 
beta magnetic signature.

In 2017 there were 11 days with a daily sunspot number (SSN) of 0. 
Considering that solar minimum won't occur for approximately three more 
years, +/- one year, seeing daily SSN's of 0 occurring now is unusually 
early.

In 2016 there were 32 days with a daily sunspot number (SSN) of 0. 
Considering that solar minimum won't occur for approximately three more 
years, seeing daily SSN's of 0 occurring now is unusually early.

As we move forward towards the next solar minimum between solar cycle #24 
and #25 the number of days with a 0 daily SSN will steadily increase. 
Eventually every day for many many many months will see a 0, the big goose 
egg.

In 2008 I fore casted solar cycle 24 to be the weakest in the past 100 years 
and that forecast verified. I also fore casted that solar cycle 25 would be 
virtually non existent, similar to the Dalton type solar minimum that 
occurred in the early 1800's. It will probably be very difficult to 
determine when solar cycle 24 ended and solar cycle 25 began.

No earth directed solar flares occurred.

No earth directed coronal mass ejections (CME) occurred.

No earth directed collapsing magnetic filament eruptions occurred.

The twenty four hour period 3 hour interval planetary K index (Kp) was at 
unsettled to quiet geomagnetic conditions of 1 1 2 1 2 3 2 2.

The maximum and minimum planetary A index (Ap) ranged between 15 and 3, 
which was at unsettled to quiet geomagnetic conditions.

The daily averaged background x-ray flux was A5.7.

The daily averaged vertical component (Bz) of earth's magnetic field was 
+0.5 nT north.

The maximum and minimum Dst ranged between +17 and -24.

No energetic proton events greater than 10 MeV (10+0) occurred.

The maximum and minimum solar wind speed was 413 and 282. km/s.

There was a recurrent trans equatorial (geoeffective) directly earth facing 
coronal hole #790 (#786). During it's last passage across the earth facing 
side of the sun it produced minor (Kp-4) negative impacts on HF radio wave 
propagation.

There was a recurrent trans equatorial earth facing coronal hole #791 
(#787). During it's last passage across the earth facing side of the sun it 
produced minor (Kp-4) negative impacts on HF radio wave propagation.
--------------------------------------------------------------------------------------

The Kp geomagnetic indices are-
0-2- quiet
3- unsettled
4- active
5- minor geomagnetic storming
6- moderate
7- strong
8- severe
9- extreme
10- our atmosphere just got cooked off like on Mars and we are all dead.

The Ap geomagnetic indices are-
0-7- quiet
8-15 unsettled
16-29- active
30-49- minor geomagnetic storm
50-99- major
100-400- severe
>401- our atmosphere just got cooked off like on Mars and we are all dead.
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GENERAL GUIDELINES CONCERNING CORRELATION OF PROPAGATION INDICES TO ACTUAL 
HF PROPAGATION CONDITIONS-

NOTE!!!  The propagation indices "interpretations" are my personal 
intellectual property. Therefore the radio wave propagation indices 
interpretations contained herein is copyrighted © 1988-2017 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 radio wave propagation possible. 
Something that happens 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.

11.) Rising positive T index number. The T Index tracks with the F2 layer 
critical frequency (foF2) and sunspot number (SSN) and indicates the 
capability of the F2 layer to refract RF signals.

12.) Galactic cosmic rays decrease to -3 units below zero and trending 
towards zero.

13.) Energetic electron flux levels no greater than 2 MeV (2+0).

14. A solar wind speed of less than 300 km/s for several days consecutively.

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Standard Disclaimer-

Note! I use error prone RAW public domain data from the NOAA Space 
Environment Center, other U.S. government organizations and educational 
institutions, to produce my comprehensive radio wave propagation forecast. 
This data is gathered and made public by the U.S. Government using taxpayer 
$$$ (including mine).

However the propagation forecast that I produce from the RAW public domain 
data is my personal intellectual property. Therefore this radio wave 
propagation forecast contained herein is copyrighted © 1988-2017 by Thomas 
F. Giella, W4HM.

Feel free to redistribute this solar, space and geomagnetic weather 
discussion and HF radio wave propagation forecast, as long as you 
redistribute it in it's entirety and give me credit for it.

Also solar, space and geomagnetic weather forecasting is still an inexact 
science. 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.


73 & GUD DX,
Thomas F. Giella, W4HM
Lakeland, FL, USA