Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 1 April 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 91 Issued at 2200Z on 01 Apr 2013

IA. Analysis of Solar Active Regions and Activity from 31/2100Z to
01/2100Z: 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 on day
one (02 Apr) and likely to be low with a slight chance for an M-class
flare on days two and three (03 – 04 Apr).

IIA. Geophysical Activity Summary 31/2100Z to 01/2100Z: 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 506 km/s at
31/2222Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 3308 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet levels on days one (02 Apr) and quiet to
unsettled levels on day two and three (03 – 04 Apr).

III. Event probabilities 02 Apr-04 Apr
Class M 05/10/10
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 01 Apr 119
Predicted 02 Apr-04 Apr 125/130/130
90 Day Mean 01 Apr 115

V. Geomagnetic A Indices
Observed Afr/Ap 31 Mar 003/004
Estimated Afr/Ap 01 Apr 005/005
Predicted Afr/Ap 02 Apr-04 Apr 004/005-009/008-007/008

VI. Geomagnetic Activity Probabilities 02 Apr-04 Apr
A. Middle Latitudes
Active 10/20/20
Minor Storm 01/05/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 15/30/30
Major-severe storm 10/25/25