:Product: 20040818RSGA.txt
:Issued: 2004 Aug 18 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 231 Issued at 2200Z on 18 Aug 2004
IA.  Analysis of Solar Active Regions and Activity from  17/2100Z
to 18/2100Z:  Solar activity has been high.  Region 656 (S15,L=87)
produced significant flare activity, including an X1.8/Sf at 18/1740
UTC.  Region 661 (N09E06) exhibited gradual growth in size over the
period, and produced several C-class flares.  New Region 662
(N12E28) was numbered today.
IB.  Solar Activity Forecast:  Solar activity is expected to be low
to moderate.  Region 661 may produce C- or M-class flares.
IIA.  Geophysical Activity Summary 17/2100Z to 18/2100Z:
The geomagnetic field has been quiet to unsettled.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be quiet to unsettled all three days.  Isolated active
conditions are possible on days two and three (20-21 Aug) from minor
effects of a small coronal hole that will reach geoeffective
position.
III.  Event Probabilities 19 Aug-21 Aug
Class M    40/20/15
Class X    10/05/01
Proton     05/05/01
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           18 Aug 140
Predicted   19 Aug-21 Aug  115/115/110
90 Day Mean        18 Aug 109
V.  Geomagnetic A Indices
Observed Afr/Ap 17 Aug  009/011
Estimated Afr/Ap 18 Aug  009/012
Predicted Afr/Ap 19 Aug-21 Aug  008/010-008/015-005/010
VI.  Geomagnetic Activity Probabilities 19 Aug-21 Aug
A.  Middle Latitudes
Active                20/30/20
Minor storm           01/05/01
Major-severe storm    01/01/01
B.  High Latitudes
Active                30/35/30
Minor storm           05/10/05
Major-severe storm    01/01/01