Report of Solar Geophysical Activity (RSGA)

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 115 Issued at 2200Z on 25 Apr 2013

IA.  Analysis of Solar Active Regions and Activity from 24/2100Z to
25/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C5 event observed at
25/1940Z. There are currently 6 numbered sunspot regions on the disk.
IB.  Solar Activity Forecast: Solar activity is expected to be low with
a chance for M-class flares on days one, two, and three (26 Apr, 27 Apr,
28 Apr).
IIA.  Geophysical Activity Summary 24/2100Z to 25/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed at ACE reached a peak of 619 km/s at 25/2014Z. Total IMF
reached 10 nT at 24/2135Z. The maximum southward component of Bz reached
-6 nT at 24/2109Z. Electrons greater than 2 MeV at geosynchronous orbit
reached a peak flux of 157 pfu.
IIB.  Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (26 Apr) and quiet levels on
days two and three (27 Apr, 28 Apr). Protons have a slight chance of
crossing threshold on days one through three (26-28 Apr).

III.  Event probabilities 26 Apr-28 Apr
Class M    40/40/30
Class X    15/15/10
Proton     15/15/10
PCAF       green

IV.  Penticton 10.7 cm Flux
Observed           25 Apr 119
Predicted   26 Apr-28 Apr 120/120/120
90 Day Mean        25 Apr 112

V.  Geomagnetic A Indices
Observed Afr/Ap 24 Apr  015/024
Estimated Afr/Ap 25 Apr  011/011
Predicted Afr/Ap 26 Apr-28 Apr  011/012-006/005-005/005

VI.  Geomagnetic Activity Probabilities 26 Apr-28 Apr
A.  Middle Latitudes
Active                15/10/10
Minor Storm           05/01/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                15/15/15
Minor Storm           25/15/15
Major-severe storm    25/10/10