Joint USAF/NOAA Solar Geophysical Activity Report and Forecast 22 December 2012

Joint USAF/NOAA Solar Geophysical Activity Report and Forecast
SDF Number 357 Issued at 2200Z on 22 Dec 2012

IA. Analysis of Solar Active Regions and Activity from 21/2100Z to
22/2100Z: 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
21/2355Z from Region 1635 (N09E35). There are currently 3 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast: Solar activity is likely to be low for the
next three days (23 – 25 December).

IIA. Geophysical Activity Summary 21/2100Z to 22/2100Z: 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 433 km/s at
22/0251Z. Total IMF reached 3.7 nT at 22/1952Z. The maximum southward
component of Bz reached -2.7 nT at 22/0316Z. Electrons greater than 2
MeV at geosynchronous orbit reached a peak level of 190 pfu.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected
to be at quiet to unsettled levels for days one and two (23 – 24
December) due to effects from a co-rotating interaction region and
coronal hole high speed stream (CH HSS). Quiet conditions are expected
to return on day three (25 December) as CH HSS effects wane.

III. Event probabilities 23 Dec-25 Dec
Class M 05/05/05
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 22 Dec 115
Predicted 23 Dec-25 Dec 120/120/120
90 Day Mean 22 Dec 120

V. Geomagnetic A Indices
Observed Afr/Ap 21 Dec 003/003
Estimated Afr/Ap 22 Dec 002/003
Predicted Afr/Ap 23 Dec-25 Dec 006/008-008/008-005/005

VI. Geomagnetic Activity Probabilities 23 Dec-25 Dec
A. Middle Latitudes
Active 10/10/05
Minor Storm 01/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 15/20/15
Minor Storm 15/20/10
Major-severe storm 05/10/05