:Product: 20040715RSGA.txt
:Issued: 2004 Jul 15 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 197 Issued at 2200Z on 15 Jul 2004
IA.  Analysis of Solar Active Regions and Activity from  14/2100Z
to 15/2100Z:  Analysis of Solar Active Regions and Activity from 
14/2100Z to 15/2100Z:  Solar activity was high. Region 649 (S10E40)
produced two impulsive X-class flares: an X1 at 0141 UTC and an X1
at 1824 UTC. Both of these events originated near the delta
configuration in the dominant trailer spot. Although the spot is not
large, the close proximity of opposite polarity spots is creating an
area of strong magnetic gradients. There was also some magnetic flux
emergence to the south of this spot during the past 24 hours. Both
of the events were compact and bright. LASCO coronagraph data did
not show a CME in association with the first X1 event. As of
forecast issue time the LASCO data seemed to indicate a slow,
relatively faint CME off the east limb in association with the
second X1 event.
IB.  Solar Activity Forecast:  Solar activity is expected to be
moderate to high, with Region 649 as the dominant source for
activity. Additional M-class flares are expected and there is a fair
chance for additional major flare activity out of 649, especially if
magnetic flux continues to emerge.
IIA.  Geophysical Activity Summary 14/2100Z to 15/2100Z:
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 tomorrow (16 July) with a chance for
some isolated active periods at higher latitudes. Conditions should
be predominantly unsettled for the 2nd and 3rd days (17-18 July).
III.  Event Probabilities 16 Jul-18 Jul
Class M    75/75/75
Class X    30/30/30
Proton     15/15/15
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           15 Jul 146
Predicted   16 Jul-18 Jul  140/140/140
90 Day Mean        15 Jul 098
V.  Geomagnetic A Indices
Observed Afr/Ap 14 Jul  006/009
Estimated Afr/Ap 15 Jul  007/010
Predicted Afr/Ap 16 Jul-18 Jul  012/020-010/012-008/010
VI.  Geomagnetic Activity Probabilities 16 Jul-18 Jul
A.  Middle Latitudes
Active                30/25/25
Minor storm           15/15/10
Major-severe storm    05/05/05
B.  High Latitudes
Active                35/30/30
Minor storm           15/15/10
Major-severe storm    05/05/05