A strange proton flux was observed today, as you can see here:
SIDC has issued this ALERT:
http://www.sidc.be/products/presto/Issued: 2011 Mar 21 0957 UTC
The proton flux measured by GOES13 increased this morning. The storm threshold is not reached. We don't expect the threshold to be passed. A back sided plasma cloud came into view of STEREO B COR2 at 02:54UT, March 21, 2011. This CME is probably associated with the increased proton levels. The Earth is magnetically connected with the source site behind the Sun. The Parker spiral has bended magnetic field lines that guide the electrically charged protons. The Earth is near such field lines along which these protons travel. This is a rare event.