Joint USAF/NOAA Report of Solar and Geophysical Activity 31 Jul 2002
:Product: Report of Solar-Geophysical Activity
:Issued: 2002 Jul 31 2210 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 212 Issued at 2200Z on 31 Jul 2002
IA. Analysis of Solar Active Regions and Activity from 30/2100Z
to 31/2100Z: Solar activity was at moderate levels. Region 39
(S15W44) produced an M1/Sb flare at 31/0153 UTC with associated
discrete frequency radio burst. This region continues its gradual
decay but maintains a delta configuration in the leader spot.
Region 50 (S08W32) has shown growth in area and spot count while
maintaining its beta-gamma magnetic configuration. Region 44
(S21W49) appears to have been relatively stable in the last 24
hours. New Region 56 (N04E49) was numbered today.
IB. Solar Activity Forecast: Solar activity is expected to be
moderate. M-class activity is expected from Region 39, Region 44 or
Region 50. An isolated X-class event is possible from Region 39.
IIA. Geophysical Activity Summary 30/2100Z to 31/2100Z:
The geomagnetic field was at quiet to unsettled levels. A weak shock
was detected at the L1 position by the NASA/ACE spacecraft at
approximately 31/1100 UTC. The Bz component of the IMF was
northward resulting in little geomagnetic activity.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled. Isolated active conditions are
possible on days one and two of the forecast period.
III. Event Probabilities 01 Aug-03 Aug
Class M 75/75/75
Class X 20/20/20
Proton 20/20/20
PCAF yellow
IV. Penticton 10.7 cm Flux
Observed 31 Jul 209
Predicted 01 Aug-03 Aug 205/200/200
90 Day Mean 31 Jul 167
V. Geomagnetic A Indices
Observed Afr/Ap 30 Jul 005/008
Estimated Afr/Ap 31 Jul 009/012
Predicted Afr/Ap 01 Aug-03 Aug 012/015-015/015-010/010
VI. Geomagnetic Activity Probabilities 01 Aug-03 Aug
A. Middle Latitudes
Active 30/35/25
Minor storm 10/15/05
Major-severe storm 01/01/01
B. High Latitudes
Active 35/40/30
Minor storm 15/20/10
Major-severe storm 01/01/01
