For my hamateur radio and SWL friends around the globe:
Feel free without
advanced permission to redistribute this "not for profit"
solar, space and
geomagnetic weather observation, 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 this daily HF radio wave
propagation
forecast can be found in my Twitter account at
https://twitter.com/GiellaW4hm and in
my Facebook account at
https://www.facebook.com/thomasfranklingiellaw4hm
My
daily solar, space & geomagnetic weather observations and discussions as
well as my daily HF radio wave propagation forecasts can also be found
at
http://lists.contesting.com/mailman/listinfo/spaceweather
and in my Facebook
account at
https://www.facebook.com/thomasfranklingiellaw4hm
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.
I'm also posting
excerpts some of my daily solar, space and geomagnetic
weather observations,
discussions and HF radio wave propagation forecasts in
my Twitter account at
https://twitter.com/GiellaW4hm
.
---------------------------------------------------------------------------------------------------------------------
#83
Issued on Saturday April 8, 2017 at 1500 UTC
Global Daily HF Radio Wave
Propagation Forecast-.
Global generalized HF radio wave propagation
conditions are
fair to good on 15-80 (15-75)
meters
and
poor to fair on 12-10 (11) meters.
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 (11) meters- very poor at night and fair at
day.
10 (11) meters- very poor at night and poor to fair at
day.
SOUTHERN 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 (11) meters- very poor at night and fair at
day.
10 (11) meters- very poor at night and poor to fair 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-
Friday April 7,
2017-
Solar activity was low.
Earth's geomagnetic field was
active.
The three daily solar flux index (SFI) numbers were 73.3 73.9
66.8.
The official daily sunspot number (SSN) was 27. On Saturday April
8, 2017
the unofficial daily sunspot number is
0.
--------------------------------------------------------------------------------------------------------------------
We
had had 15 consecutive days with a daily sunspot number of 0.
Then
suddenly on March 27, 2017 the sun awoke from its slumber and had since
then
sent the daily solar flux index and daily sunspot number, etc, rise to
levels that hadn’t been seen in many months. This went on for 10 consecutive
days.
But as of April 5, 2017 we had seen 3 consecutive days with
solar, space and
geomagnetic weather becoming quiet
again.
---------------------------------------------------------------------------------------------------------------------
In
2017 officially there were 27 days with a daily sunspot number (SSN)
of
0.
Considering that solar minimum won't occur for approximately 2
more years,
+/- 1 year, observations daily SSN's of 0 occurring now is
unusually early.
There were no earth facing sunspot groups.
There
were 2 small in size earth facing C class solar
flares,
C4.3,
C2.7.
---------------------------------------------------------------------------------------------
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 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 coronal mass ejections (CME) occurred.
No earth directed
collapsing magnetic filament eruptions occurred.
No earth directed day
side radio black outs occurred.
The twenty four hour period 3 hour
interval planetary K index (Kp) was at
unsettled to quiet geomagnetic
conditions of
3 2 2 2 1 1 2 3.
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
18
and 3,
which was at active to 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 daily averaged background x-ray flux was at
C4.34.
The daily averaged vertical component (Bz) of earth's magnetic
field was at
+1.2 nT north.
The 24 hour period maximum and minimum Dst
ranged between
-31 and -1 nT.
The 24 hour period maximum and
minimum solar wind speed ranged between
455 and 368 km/s.
There
was a recurrent northern hemisphere (geoeffective) directly earth
facing
(CH) coronal hole #800 (#795). It was shrinking in
size.
--------------------------------------------------------------------------------------
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
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.
