venerdì 6 Dicembre 2019
Breaking News
Home > Propagazione > W4HM Daily HF Radio Wave Propagation Forecast #182

W4HM Daily HF Radio Wave Propagation Forecast #182

Greetings to my hamateur radio and SWL friends around the globe:

If you find this “not for profit” daily solar, space and geomagnetic weather discussion and HF radio wave propagation forecast useful to your hamateur and SWL radio activities feel free to drop me a line and letting me know that at

thomasfgiella@gmail.com .

Feel free without advanced permission to redistribute this “not for profit”
daily solar, space and geomagnetic weather discussion and HF radio wave propagation forecast, as long as you redistribute it in its entirety and
give me credit for it.

Supporting images associated with my “not for profit” daily solar, space and geomagnetic weather discussion and HF radio wave propagation forecast can be found in my Facebook account at https://www.facebook.com/thomasfranklingiellaw4hm
and at http://lists.contesting.com/mailman/listinfo/spaceweather but without supporting images.

It’s a NO SPAM “opt” in email type group, so you have to sign up by using an existing email address and creating a password.

———————————————————————————————————————
#182 Issued on Saturday July 1, 2017 at 1700 UTC

Global Daily HF Radio Wave Propagation Forecast-

HF radio wave propagation conditions are degrading.

HAMATEUR & SW BROADCAST HF BANDS-

NORTHERN HEMISPHERE RADIO WAVE PROPAGATION-
Keep in mind that almost daily during the northern hemisphere summer season you will find that the 10 (11) meter bands 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 correctly much longer propagation paths opens up on east-west paths.

And last but not least north-south propagation paths occur across the equator via trans equatorial propagation (TEP).

Received RF signal strength scale-

HAMATEUR & SW BROADCAST HF BANDS-

NORTHERN 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.

SOUTHERN 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.

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

We are now firmly in summer/winter solstice type of HF radio wave propagation conditions.

This means generally poor HF radio wave propagation conditions in the northern hemisphere especially at day and generally good HF radio wave propagation conditions in the southern hemisphere especially at day.

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 solstice.

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).

This HF Radio wave propagation forecast is based on the NSA_Cap HF radio wave propagation prediction software.

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 VOA type curtain array antenna.

———————————————————————————————————————

Please keep in mind that this is a relatively simplified HF radio wave
propagation forecast, so as to keep it easily understandable and applicable 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 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

Friday June 30 2017-

Solar activity was very low.

Earth’s geomagnetic field was at a quiet level.

The three daily solar flux index (SFI) numbers were 71.6 71.5 72.1.

The official daily sunspot number (SSN) was 11.

Saturday July 1, 2017:

As SSG #12664 is now setting around the west limb of the sun we are on the verge of one again returning to days with no daily sunspot numbers.

In 2017 officially there were 42 days with a daily sunspot number (SSN) of
0.

Considering that solar minimum won’t occur for approximately 2 more years,
+/- 1 year, daily SSN’s of 0 are occurring now unusually early.

In 2016 officially 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 forecasted solar cycle 24 to be the weakest in the past 100 years
and that forecast verified. I also forecasted that solar cycle 25 would be
virtually nonexistent, similar to the Dalton type solar minimum that
occurred in the early 1800’s. Other than sunspot magnetic polarity it will probably be very difficult to determine when solar cycle 24 ended and solar cycle 25 began.

———————————————————————————————————————

There was 1 newly risen and/or emerged and/or existing official sun spot group (SSG).

SSG #12664 located near N17W56 with a simple alpha magnetic signature.

There were 2 unofficial and as of yet unnumbered earth facing sunspot groups (SSG) located near

N02W51,
S12W29.

No earth facing C class or larger solar flare occurred.

No energetic proton related day side high latitude solar fade out (SFO) (also related polar cap absorption) occurred.

——————————————————————————————————————–

There was a no earth facing coronal mass ejection (CME).

Saturday July 1, 2017:

But a recently released partial halo CME will strike and negatively impact earth’s geomagnetic field in 1-2 days.

There was no earth facing collapsing magnetic filament eruption.

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

0 0 1 1 1 0 1 2.

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

6 and 2,

which was at quiet geomagnetic conditions.

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.
The 24 hour period averaged energetic proton flux was at a background level below 10 MeV.

The 24 hour period averaged background x-ray flux was at A6.79.

The 24 hour period averaged vertical component (Bz) of earth’s geomagnetic magnetic field was at

-0.20 nT south.

The 24 hour period maximum and minimum disturbance storm time index (Dst) ranged between

 +2 and +26 nT.

The 24 hour period maximum and minimum solar wind speed ranged between

344 and 316 km/s.
 
There was small newly emerged southern hemisphere directly (geoeffective) earth facing coronal hole, #811.
 
Saturday July 1, 2017:
 
In the next 1-2 days a (HSS) high speed solar wind stream emanating from CH #811 will connect to earth’s geomagnetic field and begin impacting the earth’s ionosphere in a negative manner.
 
————————————————————————————–

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.

————————————————————————————

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 my comprehensive HF radio wave propagation
forecast. This data is gathered and made public by the U.S. Government using
taxpayer $$$ (including mine).

However the solar, space and geomagnetic discussions as well as the HF propagation forecast that I produce from the RAW public domain
data is my personal intellectual property. Therefore the solar, space and geomagnetic weather discussions and HF radio wave
propagation forecast contained herein is copyrighted © 1988-2017 by Thomas
F. Giella, W4HM.

Feel free without advanced permission 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 its 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.

Check Also

Propagation outlook from Boulder

:Product: Weekly Highlights and Forecasts :Issued: 2019 Dec 02 0130 UTC # Prepared by the …

Lascia un commento

Copy Protected by Chetan's WP-Copyprotect.