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Sudden Increase in Solar Activity!

Chasers and Activators,

Tonight I looked at the NOAA Space Weather Prediction Center’s website, partly because 40M was not what I expected during my activation today, and I was amazed to see how much our sun has changed in just a few days. A new active region has grown up very suddenly, and it’s full of mixed, complex magnetic fields. Suddenly we have high solar activity and related propagation conditions!

The solar flux, which had been down near 70 weeks ago, was over 180 today, we had a CME (coronal mass ejection), we already have a significant proton event at earth, and the geomagnetic activity has increased. The next few days will likely be a roller-coaster ride of solar flares, changing conditions, and radio propagation very different from the doldrums we’ve had earlier this summer!

This is where you can see the data:


Also see this site:


For incredible solar images:


The high solar flux map cause openings on 15-12-10M, maybe even 6M, and perhaps increase performance on 30-20-17-15M, but absorption will increase on 40-60-80M, especially during mid-day. The protons will increase HF absorption at high latitudes. The geomagnetic activity will increase QSB. Solar flares may cause rapid, significant short-wave fades - high absorption of HF signals on the sunlit side of the earth.

Even more inportant is that conditions will be changing, perhaps by the hour or even by the minutes, depending on what the sun is doing. This will be a great time to experience unusual conditions and to experiment. Activators, don’t just do the same bands and the same things that worked earlier in the year when the sun was quiet - try new bands! Some previously reliable bands may be so dead that you may blame your radio! For a time radio propagation will be different, and there will be surprises and opportunities.

Let’s enjoy this sudden increase in solar activity!




UK amateurs should hopefully find this site useful. It’s the work of the well know meteorologist Jim Bacon, G3YLA. It’s complied using the data from the Fairford Ionosonde and is particularly useful in showing the FoF2 and FoEs critical frequencies with NVIS propagation in mind.


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Digging thru websites and trying to learn how to read ionograms has been part of my learning experience.

Ionograms from 4 sites: http://wdc.nict.go.jp/ionog/ionogram/nowpng/allsite.html
Current fxEs values: http://wdc.nict.go.jp/IONO/fxEs/latest-fxEs.html
Propagation summary (oblique & vertical): http://wdc.nict.go.jp/IONO/oblver/index.html

For the curious, the Tokyo ionosonde site is Kokubunji. http://wdc.nict.go.jp/IONO/HP2009/contents/Ionosonde_Map_E.html