Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 4 April 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 94 Issued at 2200Z on 04 Apr 2013

IA. Analysis of Solar Active Regions and Activity from 03/2100Z to
04/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C1 event observed at
04/0957Z from Region 1713 (N09W06). There are currently 7 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast: Solar activity is likely to be low with a
slight chance for an M-class flare on days one, two, and three (05 Apr,
06 Apr, 07 Apr).

IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z: The geomagnetic
field has been at quiet levels for the past 24 hours. Solar wind speed,
as measured by the ACE spacecraft, reached a peak speed of 364 km/s at
04/1508Z. Total IMF reached 6 nT at 04/0906Z. The maximum southward
component of Bz reached -4 nT at 04/0918Z. Electrons greater than 2 MeV
at geosynchronous orbit reached a peak level of 3225 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels on days one and three (05 Apr, 07 Apr) and quiet
to unsettled levels on day two (06 Apr).

III. Event probabilities 05 Apr-07 Apr
Class M 10/10/10
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 04 Apr 129
Predicted 05 Apr-07 Apr 130/130/130
90 Day Mean 04 Apr 114

V. Geomagnetic A Indices
Observed Afr/Ap 03 Apr 003/003
Estimated Afr/Ap 04 Apr 004/005
Predicted Afr/Ap 05 Apr-07 Apr 006/005-009/008-005/005

VI. Geomagnetic Activity Probabilities 05 Apr-07 Apr
A. Middle Latitudes
Active 10/10/10
Minor Storm 01/05/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 20/20/20
Major-severe storm 20/15/20