:Product: 1218RSGA.txt
:Issued: 2009 Dec 18 2200 UTC
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
# Space Weather Prediction Center and the U.S. Air Force.
#
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 352 Issued at 2200Z on 18 Dec 2009
IA.  Analysis of Solar Active Regions and Activity from  17/2100Z
to 18/2100Z:  Solar activity has been low.  One C-class event
occurred from Region 1035 (N30W45).  It was an optically
uncorrelated, impulsive C7.6 observed at 18/1855Z.  Numerous B-class
events were also observed throughout the period.  Region 1035
continues to grow in area (310 millionths), longitudinal extent (12
degrees) and spot count (14 spots).  However, during the past 24
hours, the large negative polarity penumbra and associated umbra
located near region center decayed resulting in a beta magnetic
configuration for the region.
IB.  Solar Activity Forecast:  Solar activity is expected to be low. 
There is a slight chance for an isolated M-class event from Region
1035.
IIA.  Geophysical Activity Summary 17/2100Z to 18/2100Z:
The geomagnetic field has been quiet.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be quiet for day one (19 December) of the forecast
period.  An increase to unsettled to active levels is expected on
day two (20 December).  The increase in activity levels is due to
the expected arrival of the CME observed on 16 December.  By day
three (21 December), the field will return to mostly quiet levels.
III.  Event Probabilities 19 Dec-21 Dec
Class M    10/10/10
Class X    01/01/01
Proton     01/01/01
PCAF       Green
IV.  Penticton 10.7 cm Flux
Observed           18 Dec 084
Predicted   19 Dec-21 Dec  085/085/083
90 Day Mean        18 Dec 073
V.  Geomagnetic A Indices
Observed Afr/Ap 17 Dec  002/001
Estimated Afr/Ap 18 Dec  002/005
Predicted Afr/Ap 19 Dec-21 Dec  005/005-015/015-007/007
VI.  Geomagnetic Activity Probabilities 19 Dec-21 Dec
A.  Middle Latitudes
Active                15/45/15
Minor storm           05/15/05
Major-severe storm    01/05/01
B.  High Latitudes
Active                20/50/20
Minor storm           10/20/10
Major-severe storm    01/10/01