mercoledì 19 giugno 2019

W4HM Daily HF-MF Radio Wave Propagation Forecast #2019-171

Greetings to my fellow hamateur radio and SWL radio enthusiasts around the
world.

Welcome to my “not for profit” W4HM Daily HF-MF Radio Wave Propagation Forecast.

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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.

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I'm a semiretired heliophysicist, troposphere meteorologist/climatologist, physical oceanographer and one of the few on the planet with advanced education and forecast experience in all aforementioned disciplines. In troposphere weather forecasting I have 46 years of experience and in solar, space and geomagnetic weather forecasting 31 years. In physical oceanography 10 years.

This is created and disseminated by Thomas F. Giella, W4HM in Lakeland, FL, USA © 1988-2019.

You can contact me at thomasfgiella@gmail.com  

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W4HM Solar Cycle 24 Update and Solar Cycle 25 Forecast- Short and to the point.

Solar minimum will begin later in 2019-2020 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 (harmful man induced global warming) if it were occurring, WHICH IT ISN’T.

For more “TRUTH” on the communist-marxist-socialist lie of anthropogenic climate change (harmful man induced global warming) check out https://wattsupwiththat.com and http://www.climatedepot.com

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 SSN <50.

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#171 Wednesday Jun 19, 2019 at 1630 UTC

Important Solar, Space & Geomagnetic Weather Indices-

The daily solar flux index numbers (DSFI) were

66.7 67.0 66.4.

The official daily sunspot number (DSSN) was 0.

There had been 31 consecutive days with an official sunspot number (DSSN) of 0.

In 2019 there had been 105 days with an official daily sunspot number (DSSN) of 0.

The 24 hour period 3 hour interval planetary K index (Kp) had been at a quiet geomagnetic condition of

0 0 0 0 1 1 1 1.

GLOBAL (HF-MF 3000-30000 kHz- 300-3000 kHz) RADIO WAVE PROPAGATION CONDITIONS EXPECTED-

Radio wave propagation condition “trend” on Jun 19, 2019- steady.

Radio wave propagation condition “trend” on Jun 20, 2019- minor deterioration.

Radio wave propagation condition “trend” on Jun 21, 2019- steady.

We are now into the northern hemisphere HF-MF radio wave propagation summer 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 daily 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).

NORTHERN HEMISPHERE HIGH FREQUENCY (HF) RADIO WAVE PROPAGATION FORECAST s g-

Received RF signal strength scale-
Very Good- +1 over S9 or greater
Good- S7-9
Fair- S4-6
Poor- S1-3
Very Poor- S0

3150-3400, 3500-4100, 4750-5050, 5700-6300 kHz- S9 at night and S1-2 at day,

6900-7800, 9200-9995, 10000-10150, 11500-12200 kHz- S9+ 1 at night and
S4-7 at day,

13570-13850, 14000-14350, 15005-15900, 17450-17950, 18068-18168 kHz- S0 at night and S4-6 at day,

21000-21850 kHz- S0 at night and S1-2 at day,

24890-24990, 25600-26100 kHz- S0 at night and S0-1 at day,
28000-29700 kHz- S0 at night and S0 at day.

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We are now into the southern hemisphere HF-MF radio wave propagation winter season.
The approximate 11000- 30000 kHz frequency range closes sooner due to less sun light illuminating the ionosphere than in the northern hemisphere. But the maximum usable frequency (MUF) is higher than in the northern 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 layer and therefore less RF signal absorption.
A weaker and shorter sporadic E (Es) season occurs during winter time.

SOUTHERN HEMISPHERE HIGH FREQUENCY (HF) RADIO WAVE PROPAGATION FORECAST w g-

3150-3400, 3500-4100, 4750-5050, 5700-6300 kHz- S9+15 at night and S4-5 at day,

6900-7800, 9200-9995, 10000-10150, 11500-12200 kHz- S9+20 at night and
S8-9 at day,

13570-13850, 14000-14350, 15005-15900, 17450-17950, 18068-18168 kHz- S0 at night and S8-9 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.

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GLOBAL MEDIUM FREQUENCY (MF) (300-3000 KHZ) RADIO WAVE PROPAGATION CONDITIONS EXPECTED-

Received RF signal strength scale-
Very Good- +1 over S9 or greater
Good- S7-9
Fair- S4-6
Poor- S1-3
Very Poor- S0


FORECASTED NORTHERN HEMISPHERE SHORT PATH-
-East <-> West To 1100 Mi /1800 km
S7-8
*North <-> South To 1100 Mi /1800 km
S7-8
+South <-> North To 1100 Mi /1800 km
S3-4

FORECASTED SOUTHERN HEMISPHERE SHORT PATH-
-East <-> West To 1100 Mi / 1800 km
S9+1
*South <-> North To 1100 Mi /1800 km
S8-9
+North <-> South To 1100 Mi / 1800 km
S2-3

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
S5-6
Mid Latitude
S7-8
Low latitude
S5-6

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
S6-7
Mid Latitude
S9+5
Low latitude
S6-7


Received RF signal strength scale-
Very Good- +1 over S9 or greater
Good- S7-9
Fair- S4-6
Poor- S1-3
Very Poor- S0

This HF-MF Radio wave propagation forecast is produced based on the SIGINT_CAP HF-MF radio wave propagation prediction software. X and O ray tracing is included.
I wrote it beginning in the late 1980’s and continue to refine it in 2019.
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.

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.