Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 23 September 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 266 Issued at 2200Z on 23 Sep 2013

IA. Analysis of Solar Active Regions and Activity from 22/2100Z to
23/2100Z: Solar activity has been at very low levels for the past 24
hours. There are currently 5 numbered sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is likely to be low on days
one, two, and three (24 Sep, 25 Sep, 26 Sep).

IIA. Geophysical Activity Summary 22/2100Z to 23/2100Z: 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 425 km/s at
23/0304Z. Total IMF reached 5 nT at 23/0844Z. The maximum southward
component of Bz reached -4 nT at 23/1643Z. Electrons greater than 2 MeV
at geosynchronous orbit reached a peak level of 1893 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on day one (24 Sep) and quiet levels
on days two and three (25 Sep, 26 Sep).

III. Event probabilities 24 Sep-26 Sep
Class M 05/05/05
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 23 Sep 108
Predicted 24 Sep-26 Sep 108/108/108
90 Day Mean 23 Sep 111

V. Geomagnetic A Indices
Observed Afr/Ap 22 Sep 006/007
Estimated Afr/Ap 23 Sep 005/005
Predicted Afr/Ap 24 Sep-26 Sep 008/008-004/005-004/005

VI. Geomagnetic Activity Probabilities 24 Sep-26 Sep
A. Middle Latitudes
Active 10/05/05
Minor Storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 25/15/15
Major-severe storm 10/05/05