Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 13 August 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 225 Issued at 2200Z on 13 Aug 2013

IA. Analysis of Solar Active Regions and Activity from 12/2100Z to
13/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C4 event observed at
13/1850Z from Region 1809 (N14W0*). There are currently 5 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 (14 Aug, 15 Aug,
16 Aug).

IIA. Geophysical Activity Summary 12/2100Z to 13/2100Z: The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
437 km/s at 13/1935Z. Total IMF reached 10 nT at 13/1803Z. The maximum
southward component of Bz reached -8 nT at 13/1518Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 661 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at unsettled to minor storm levels on day one (14 Aug), quiet to
active levels on day two (15 Aug) and quiet to unsettled levels on day
three (16 Aug).

III. Event probabilities 14 Aug-16 Aug
Class M 30/30/30
Class X 05/05/05
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 13 Aug 122
Predicted 14 Aug-16 Aug 120/120/125
90 Day Mean 13 Aug 114

V. Geomagnetic A Indices
Observed Afr/Ap 12 Aug 006/005
Estimated Afr/Ap 13 Aug 005/006
Predicted Afr/Ap 14 Aug-16 Aug 015/018-012/015-010/010

VI. Geomagnetic Activity Probabilities 14 Aug-16 Aug
A. Middle Latitudes
Active 30/30/15
Minor Storm 15/15/05
Major-severe storm 01/05/01
B. High Latitudes
Active 15/15/15
Minor Storm 35/30/25
Major-severe storm 40/50/25