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

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 247 Issued at 2200Z on 04 Sep 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 C3 event observed at
04/0428Z from Region 1837 (S15W47). There are currently 4 numbered
sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is likely to be low on days
one and two (05 Sep, 06 Sep) and expected to be very low with a chance
for a C-class flares on day three (07 Sep).

IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z: The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
507 km/s at 04/0850Z. Total IMF reached 5 nT at 03/2300Z. The maximum
southward component of Bz reached -4 nT at 03/2142Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 1230 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on days one and two (05 Sep, 06 Sep)
and quiet levels on day three (07 Sep).

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

IV. Penticton 10.7 cm Flux
Observed 04 Sep 109
Predicted 05 Sep-07 Sep 110/105/105
90 Day Mean 04 Sep 114

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

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