Report of Solar-Geophysical Activity

Issued: 2012 May 28 2200 UTC
Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Weather Prediction Center and the U.S. Air Force.

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 149 Issued at 2200Z on 28 May 2012

IA.  Analysis of Solar Active Regions and Activity from  27/2100Z
to 28/2100Z:  Solar activity was very low.  Region 1491 (N22W70)
produced a B7 flare at 28/1249Z, which was the largest flare of the
period.  Region 1490 (S13E04) produced three nominal B-class flares
during the period.  A CME associated with a filament eruption was
observed in LASCO C2 imagery at 28/0800Z off of the northwest
quadrant of the solar disk.  The CME does not appear to be Earth
directed.
IB.  Solar Activity Forecast:  Solar activity is expected to be very
low to low for the next three days (29-31 May).
IIA.  Geophysical Activity Summary 27/2100Z to 28/2100Z:
The geomagnetic field was quiet to unsettled. The greater than 2 MeV
electron flux at geosynchronous orbit reached high levels during the
period.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be mostly quiet for the next three days (29-31 May).
III.  Event Probabilities 29 May-31 May
Class M    05/05/05
Class X    01/01/01
Proton     01/01/01
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           28 May 110
Predicted   29 May-31 May  110/110/110
90 Day Mean        28 May 117
V.  Geomagnetic A Indices
Observed Afr/Ap 27 May  003/005
Estimated Afr/Ap 28 May  005/007
Predicted Afr/Ap 29 May-31 May  004/005-004/005-004/005
VI.  Geomagnetic Activity Probabilities 29 May-31 May
A.  Middle Latitudes
Active                05/05/05
Minor storm           01/01/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor storm           10/10/10
Major-severe storm    05/05/05

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 1909
Begin Time: 2012 May 24 1235 UTC
Yesterday Maximum 2MeV Flux: 2753 pfu

NOAA Space Weather Scale descriptions can be found at
www.swpc.noaa.gov/NOAAscales

Potential Impacts: Satellite systems may experience significant charging resulting in increased risk to satellite systems.