:Product: 20020721RSGA.txt
:Issued: 2002 Jul 21 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 202 Issued at 2200Z on 21 Jul 2002
IA.  Analysis of Solar Active Regions and Activity from  20/2100Z
to 21/2100Z:  Solar activity was high. The event in progress at issue
time yesterday, from behind the east limb near S10, reached  the X3
level at 20/2130UTC. There was an associated type II sweep and
tenflare. The site of the activity has, as yet, failed to fully
appear, but should do so in the next 24 hours. Some plage and
faculae are now visible in that vicinity. Elsewhere, Regions 30
(N18W76) and 36 (S06W02) continue to impress in white light and
H-alpha, but have been relatively quiet. One new region, 38
(N17E51), was assigned.
IB.  Solar Activity Forecast:  Solar activity is expected to be
moderate. Watch the east limb for more energetic activity over the
next three days.
IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z:
The geomagnetic field was at quiet to minor storm levels during the
period. Faster than normal solar wind, with some southward Bz,
brought periods of minor storm conditions to local nighttime
sectors. An enhancement in the greater than 10 MeV protons has
occurred, with current readings near 5 pfu. The greater than 2 MeV
electrons at geosynchronous orbit reached high levels for a few
hours near midday.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be unsettled to mildly active for the next three days.
III.  Event Probabilities 22 Jul-24 Jul
Class M    70/70/70
Class X    20/20/20
Proton     20/20/20
PCAF       yellow
IV.  Penticton 10.7 cm Flux
Observed           21 Jul 183
Predicted   22 Jul-24 Jul  185/185/185
90 Day Mean        21 Jul 161
V.  Geomagnetic A Indices
Observed Afr/Ap 20 Jul  013/018
Estimated Afr/Ap 21 Jul  015/018
Predicted Afr/Ap 22 Jul-24 Jul  010/012-010/010-010/010
VI.  Geomagnetic Activity Probabilities 22 Jul-24 Jul
A.  Middle Latitudes
Active                30/30/30
Minor storm           15/15/15
Major-severe storm    05/05/05
B.  High Latitudes
Active                40/40/40
Minor storm           15/15/15
Major-severe storm    05/05/05