Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 19 September 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 262 Issued at 2200Z on 19 Sep 2013

IA. Analysis of Solar Active Regions and Activity from 18/2100Z to
19/2100Z: Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C1 event observed at
19/0817Z from Region 1850 (N09E75). There are currently 7 numbered
sunspot regions on the disk.

IB. Solar Activity Forecast: Solar activity is expected to be very low
with a chance for a C-class flares on days one, two, and three (20 Sep,
21 Sep, 22 Sep).

IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z: 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
600 km/s at 18/2127Z. Total IMF reached 7 nT at 18/2137Z. The maximum
southward component of Bz reached -5 nT at 19/0715Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 414 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on day one (20 Sep) and quiet levels
on days two and three (21 Sep, 22 Sep).

III. Event probabilities 20 Sep-22 Sep
Class M 05/05/05
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 19 Sep 108
Predicted 20 Sep-22 Sep 110/110/110
90 Day Mean 19 Sep 111

V. Geomagnetic A Indices
Observed Afr/Ap 18 Sep 006/007
Estimated Afr/Ap 19 Sep 010/012
Predicted Afr/Ap 20 Sep-22 Sep 007/008-005/005-005/005

VI. Geomagnetic Activity Probabilities 20 Sep-22 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