Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 24 August 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 236 Issued at 2200Z on 24 Aug 2013

IA. Analysis of Solar Active Regions and Activity from 23/2100Z to
24/2100Z: Solar activity has been at very low levels for the past 24
hours. There are currently 8 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is likely to be low on days
one and two (25 Aug, 26 Aug) and expected to be very low with a chance
for a C-class flares on day three (27 Aug).

IIA. Geophysical Activity Summary 23/2100Z to 24/2100Z: 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 532 km/s at
24/0729Z. Total IMF reached 8 nT at 24/0116Z. The maximum southward
component of Bz reached -4 nT at 24/1225Z. Electrons greater than 2 MeV
at geosynchronous orbit reached a peak level of 3575 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to minor storm levels on day one (25 Aug) and quiet to
unsettled levels on days two and three (26 Aug, 27 Aug).

III. Event probabilities 25 Aug-27 Aug
Class M 05/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 24 Aug 117
Predicted 25 Aug-27 Aug 115/110/105
90 Day Mean 24 Aug 113

V. Geomagnetic A Indices
Observed Afr/Ap 23 Aug 014/016
Estimated Afr/Ap 24 Aug 009/012
Predicted Afr/Ap 25 Aug-27 Aug 019/020-011/012-009/008

VI. Geomagnetic Activity Probabilities 25 Aug-27 Aug
A. Middle Latitudes
Active 40/20/15
Minor Storm 30/05/01
Major-severe storm 10/01/01
B. High Latitudes
Active 05/15/15
Minor Storm 20/30/25
Major-severe storm 75/30/20