:Product: 20001219RSGA.txt
:Issued: 2000 Dec 19 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 354 Issued at 2200Z on 19 Dec 2000
IA.  Analysis of Solar Active Regions and Activity from  18/2100Z
to 19/2100Z:  Solar activity was low. Region 9278 (N09E37) produced
today's largest event, a C9/Sf at 1024Z. The region covers a
relatively small area, but showed additional brightenings and
subflares during the past 24 hours. Region 9279 (S11E54) contributed
a C3/1f at 18/2312Z. New region 9280 (N10E72) rotated into view
today as a moderate-sized D-type group but has been stable so far.
IB.  Solar Activity Forecast:  Solar activity is expected to be low,
but there is a slight-to-fair chance for an isolated M-class event
sometime over the next three days.
IIA.  Geophysical Activity Summary 18/2100Z to 19/2100Z:
The geomagnetic field was quiet to unsettled during the past 24
hours.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be mostly unsettled during the next 24 hours. An
increase to mostly active is expected during the 2nd and 3rd days as
a response to the full-halo CME that occurred on 18 December.
III.  Event Probabilities 20 Dec-22 Dec
Class M    35/35/35
Class X    01/01/01
Proton     01/01/01
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           19 Dec 199
Predicted   20 Dec-22 Dec  200/200/195
90 Day Mean        19 Dec 176
V.  Geomagnetic A Indices
Observed Afr/Ap 18 Dec  007/010
Estimated Afr/Ap 19 Dec  005/010
Predicted Afr/Ap 20 Dec-22 Dec  010/012-025/025-025/025
VI.  Geomagnetic Activity Probabilities 20 Dec-22 Dec
A.  Middle Latitudes
Active                25/30/30
Minor storm           10/25/25
Major-severe storm    05/20/20
B.  High Latitudes
Active                25/30/30
Minor storm           10/25/25
Major-severe storm    05/20/20