:Product: 1216RSGA.txt
:Issued: 2006 Dec 16 2234 UTC
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
# Space Environment Center and the U.S. Air Force.
#
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 350 Issued at 2200Z on 16 Dec 2006
IA.  Analysis of Solar Active Regions and Activity from  15/2100Z
to 16/2100Z:  Solar activity declined to very low levels today. 
Region 930 (S06W72) remains a magnetically complex region.  Some
decay was noted in the penumbra of the delta structure in the
southern portion of the large asymmetrical sunspot.  Several minor
B-class flares were observed during the period from Region 930.  No
new regions were numbered today.
IB.  Solar Activity Forecast:  Solar activity is expected to be at
moderate to high levels.  Region 930 remains capable of producing an
isolated X-class flare.
IIA.  Geophysical Activity Summary 15/2100Z to 16/2100Z:
The geomagnetic field was at quiet to active levels. The elevated
conditions were due to the lingering effects of the transient
resulting from the X3 flare that occurred on 13 December.  A shock
passage was observed at the ACE spacecraft at approximately 16/1722Z
which was followed by a Sudden Impulse at the Boulder magnetometer
at 16/1756Z (13 nT).  This latest disturbance is associated with the
X1 flare that occurred on 14 December.  The greater than 2 MeV
electron flux at geosynchronous orbit reached high levels again
today.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to range from active to major storm levels with isolated
severe storm conditions possible on 17 December due to the effects
of today's transient passage.  A return to quiet to unsettled levels
are expected on 18 and 19 December.
III.  Event Probabilities 17 Dec-19 Dec
Class M    60/25/10
Class X    25/05/01
Proton     25/05/01
PCAF       yellow
IV.  Penticton 10.7 cm Flux
Observed           16 Dec 082
Predicted   17 Dec-19 Dec  080/075/075
90 Day Mean        16 Dec 081
V.  Geomagnetic A Indices
Observed Afr/Ap 15 Dec  048/104
Estimated Afr/Ap 16 Dec  010/010
Predicted Afr/Ap 17 Dec-19 Dec  030/040-008/010-004/005
VI.  Geomagnetic Activity Probabilities 17 Dec-19 Dec
A.  Middle Latitudes
Active                30/20/15
Minor storm           35/10/05
Major-severe storm    35/05/01
B.  High Latitudes
Active                20/25/20
Minor storm           40/10/05
Major-severe storm    35/05/01