LF: Propagation Anomaly

["Markus Vester" <markusvester@aol.com>]

Dear LF,

 

yesterday around 12 UT, there was an unusual skywave outage on the path from Northern European Loran-C stations Jan Mayen and Bo, lasting about 45 minutes. It is visible as an interruption of the four purple strips on

http://df6nm.bplaced.net/LoranView/LoranView_110402_0800-1600.jpg

 

This is reminiscent but quite different from the usual SID effects, which are normally induced by solar x-ray flares and would have affected the whole sunlit hemisphere at once. In this case, more southerly and easterly paths were unchanged. Also no pronounced dip or enhancement appeared on any of the VLF MSK signals. The NOAA space-weather site

http://www.swpc.noaa.gov/today.html

has no indication of a significant x-ray burst at the time, albeit a generally high level of magnetic activity.

 

Any ideas?

 

Best 73,

Markus (DF6NM)