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[RTTY] W4HM Daily HF Propagation Forecast

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Subject: [RTTY] W4HM Daily HF Propagation Forecast
From: "Thomas F. Giella W4HM" <thomasfgiella@gmail.com>
Date: Sun, 12 Feb 2017 09:25:17 -0500
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For my hamateur radio and SWL friends around the globe:

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

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.

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.

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

Issued on Sunday February 12, 2017 at 1200 UTC

Global HF Radio Wave Propagation Forecast

HAMATEUR & SW BROADCAST HF BANDS:

NORTHERN HEMISPHERE RADIO WAVE PROPAGATION-

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

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

20-17 (22-15) meters- very poor at night and good at day,

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

12-10 (11) meters- very poor at night and 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 (22-15) 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.
------------------------------------------------------------------------------------
Solar Space & Geomagnetic Weather Conditions On

Saturday February 11, 2017-

Solar activity was low.

Earth's magnetic field was quiet.

The solar flux index (SFI) was 75.5 75.7 75.6.

The official daily sunspot number (SSN) was 18.

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, seeing daily SSN's of 0 is occurring 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 is occurring 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 sunspot number will dramatically increase. Eventually most every day for many many months will see a 0.

In 2008 I forecasted solar cycle 24 to be the weakest in the past 100 years and that came forecast verified. I also forecasted that solar cycle 25 would be virtually non existent, similar to the Dalton type solar minimum that occurred in the early 1800's.

Sunspot group #12635 was located near N13E01 with a simple beta magnetic signature.

No earth directed solar flares occurred.

No earth directed coronal mass ejections (CME) occurred.

No earth directed collapsing magnetic filament eruptions occurred.

The 24 hour period 3 hour interval planetary K index (Kp) was at quiet geomagnetic conditions 2 1 2 1 2 2 1 2.

The maximum and minimum planetary A index (Ap) ranged between 9 and 4, which was at unsettled to quiet geomagnetic conditions.

The averaged background x-ray flux was A6.2.

The vertical component (Bz) of earth's magnetic field was -1.0 nT south.

The Dst ranged between -21 and +9.

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

The maximum and minimum solar wind speed was 436 and 369. km/s.

There was a recurrent transequatorial 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.
--------------------------------------------------------------------------------------

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.
------------------------------------------------------------------------------------

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.

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.

------------------------------------------------------------------------------------

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 implie d.
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