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

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 124 Issued at 2200Z on 04 May 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 C5 event observed at
04/1236Z from Region 1739 (N13E57). There are currently 9 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 (05 May, 06 May,
07 May).

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 417 km/s at
03/2131Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 2096 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to active levels on day one (05 May) and quiet to
unsettled levels on days two and three (06 May, 07 May).

III. Event probabilities 05 May-07 May
Class M 45/45/45
Class X 05/05/05
Proton 05/05/05
PCAF green

IV. Penticton 10.7 cm Flux
Observed 04 May 142
Predicted 05 May-07 May 142/140/140
90 Day Mean 04 May 116

V. Geomagnetic A Indices
Observed Afr/Ap 03 May 005/007
Estimated Afr/Ap 04 May 006/007
Predicted Afr/Ap 05 May-07 May 008/010-007/008-008/008

VI. Geomagnetic Activity Probabilities 05 May-07 May
A. Middle Latitudes
Active 20/10/10
Minor Storm 05/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/20
Minor Storm 30/25/20
Major-severe storm 25/20/10