Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 21 October 2013

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 294 Issued at 2200Z on 21 Oct 2013

IA. Analysis of Solar Active Regions and Activity from 20/2100Z to
21/2100Z: 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
21/0813Z. There are currently 8 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 (22 Oct, 23 Oct,
24 Oct).

IIA. Geophysical Activity Summary 20/2100Z to 21/2100Z: 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 408 km/s at
21/1942Z. Total IMF reached 5 nT at 21/1703Z. The maximum southward
component of Bz reached -3 nT at 21/1416Z. Electrons greater than 2 MeV
at geosynchronous orbit reached a peak level of 3951 pfu.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels on days one and three (22 Oct, 24
Oct) and quiet levels on day two (23 Oct).

III. Event probabilities 22 Oct-24 Oct
Class M 30/30/30
Class X 05/05/05
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 21 Oct 136
Predicted 22 Oct-24 Oct 135/135/135
90 Day Mean 21 Oct 112

V. Geomagnetic A Indices
Observed Afr/Ap 20 Oct 003/002
Estimated Afr/Ap 21 Oct 008/009
Predicted Afr/Ap 22 Oct-24 Oct 009/008-006/005-006/008

VI. Geomagnetic Activity Probabilities 22 Oct-24 Oct
A. Middle Latitudes
Active 15/05/15
Minor Storm 05/01/05
Major-severe storm 01/01/01
B. High Latitudes
Active 15/15/15
Minor Storm 20/15/20
Major-severe storm 20/10/20