:Product: 20041231RSGA.txt
:Issued: 2004 Dec 31 2200 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 366 Issued at 2200Z on 31 Dec 2004
IA.  Analysis of Solar Active Regions and Activity from  30/2100Z
to 31/2100Z:  Solar activity was at moderate levels today.  Region
715 (N04E34) produced an M4/2n event that occurred at 30/2218Z along
with an associated Tenflare (230 sfu), a Type IV spectral radio
sweep, and a Type II spectral radio sweep with an estimated shock
velocity of 1378 km/s.  A related CME was observed on LASCO imagery
which appears to have a slight Earth directed component.  A more
recent M1 x-ray flare occurred at 31/1445Z from this region, and due
to insufficient data, it is uncertain whether this flare produced a
CME.  White light analysis has shown a decay in sunspot area over
the period although a small delta magnetic structure can be seen in
the southern most cluster of the penumbral spots.  The remainder of
the disk/limbs were quiescent today.  A new region was numbered
today as Region 717 (N07W56).
IB.  Solar Activity Forecast:  Solar activity is expected to be at
low to moderate levels.  Region 715 remains capable of producing
M-class flare activity.
IIA.  Geophysical Activity Summary 30/2100Z to 31/2100Z:
The geomagnetic field was at quiet to unsettled levels today.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be at quiet to unsettled levels through day one (1 Jan)
of the period.  A recurrent high speed coronal hole stream and the
CME's that occurred yesterday in response to the M2/Sf event and the
M4/2n event that occurred today should induce active to minor storm
conditions on days two and three (2-3 Jan).
III.  Event Probabilities 01 Jan-03 Jan
Class M    60/50/50
Class X    10/10/10
Proton     05/05/05
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           31 Dec 099
Predicted   01 Jan-03 Jan  100/100/095
90 Day Mean        31 Dec 105
V.  Geomagnetic A Indices
Observed Afr/Ap 30 Dec  012/015
Estimated Afr/Ap 31 Dec  008/009
Predicted Afr/Ap 01 Jan-03 Jan  008/012-015/020-015/015
VI.  Geomagnetic Activity Probabilities 01 Jan-03 Jan
A.  Middle Latitudes
Active                20/35/35
Minor storm           01/15/15
Major-severe storm    01/05/05
B.  High Latitudes
Active                25/40/35
Minor storm           05/20/15
Major-severe storm    01/10/05