A, K, and Flux Indices Now on w5sc.org Homepage

davidftx <davidftx@...>

Standard HF propagation indicators are the Planetary A Index of
Geomagnetic Activity, the Planetary K Index of Geomagnetic Activity, and
the Solar Flux Index. The data for these indices is updated
periodically and is posted in the U.S. on WWV and the Internet.
Understanding the measurements of activity requires an in depth study of
physics, mathematics, and theories of space weather. But HF radio
amateurs have learned to look to these three numbers as an indicator of
how good, or how bad, the HF bands are for propagation at any given

Paul Guido has placed a Hamquick Propcast on the home page of w5sc.org
<http://groups.yahoo.com/group/W5SC/w5sc.org> . It is located on the
left side of the page under the menu and it updates itself as the
numbers are updated.

In a very simplistic nutshell here is what the numbers mean to HF

A Index-effects of solar radiation. Under 10 is good. Over 30 is bad.
Wish for single digits

K Index-A different, more immediate measurement at Boulder, CO. 0 is
great. Lower = better. Again, wish for single digits.

Flux Index-Solar Flux measured in British Columbia. 65 to 300 and
higher is better. 65 is horrible. Over 200 is very good. During this
time of the solar cycle we won't see any 200's with a relative
decent day being around 100 or little less.

NOAA and others use these observations to predict space weather and its
effect on propagation. Those forecasts are included in the Propcast on
w5sc.org <http://groups.yahoo.com/group/W5SC/w5sc.org> .

NOAA has some very fine articles on Solar Weather and particularly
Flares at http://www.ngdc.noaa.gov/stp/SOLAR/solar.html

A good resource for Solar Weather information complete with great links
is http://www.k-state.edu/ksuarc/solar.html
<http://www.k-state.edu/ksuarc/solar.html> .

A little more details on short term Space Weather (and indices)
forecasts is here http://www.ngdc.noaa.gov/stp/SOLAR/solar.html

Thanks Paul, this is a great resource.

Join main@saradioclub.groups.io to automatically receive all group messages.