Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 31 March 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 90 Issued at 2200Z on 31 Mar 2013

IA. Analysis of Solar Active Regions and Activity from 30/2100Z to
31/2100Z: Solar activity has been at very low levels for the past 24
hours. There are currently 6 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 (01 Apr,
02 Apr, 03 Apr).

IIA. Geophysical Activity Summary 30/2100Z to 31/2100Z: 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 579 km/s at
30/2143Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 3680 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels on days one and two (01 Apr, 02 Apr) and quiet to
unsettled levels on day three (03 Apr).

III. Event probabilities 01 Apr-03 Apr
Class M 10/10/15
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 31 Mar 113
Predicted 01 Apr-03 Apr 120/125/130
90 Day Mean 31 Mar 115

V. Geomagnetic A Indices
Observed Afr/Ap 30 Mar 012/016
Estimated Afr/Ap 31 Mar 003/004
Predicted Afr/Ap 01 Apr-03 Apr 004/005-004/005-009/008

VI. Geomagnetic Activity Probabilities 01 Apr-03 Apr
A. Middle Latitudes
Active 05/10/20
Minor Storm 01/01/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 15/15/30
Major-severe storm 05/10/25