:Product: 20011020RSGA.txt
:Issued: 2001 Oct 20 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 293 Issued at 2200Z on 20 Oct 2001
::::::CORRECTED COPY:::::::
IA.  Analysis of Solar Active Regions and Activity from  19/2100Z
to 20/2100Z:  Solar activity was at moderate levels.  Region 9658
(S15W73) produced an M3/1f flare at 20/2325 UTC and associated
discrete frequency radio bursts.  Other activity was centered around
Region's 9661 (N15W48) and 9670 (S19E19).  Both of these regions
produced minor C-class flares though the course of the period.
Region 9661 was generally stable and has shown gradual decay as the
magnetic delta configuration is no longer apparent in regions spot
group.  Two new regions were numbered today, Region 9675 (S14E69),
and Region 9676 (N13E70).
IB.  Solar Activity Forecast:  Solar activity is expected to be at
moderate to high levels.  Region 9661 still remains capable of
producing an M-class or isolated major flares.
IIA.  Geophysical Activity Summary 19/2100Z to 20/2100Z:
The geomagnetic field was predominantly at quiet to unsettled levels.
Brief active conditions were observed at both the middle and high
latitudes in the 20/1200-1500 UTC period.  The greater than 10 MeV
proton flux at geosynchronous orbit passed the 10 pfu threshold at
19/2225 UTC, reached a maximum of 11 pfu at 19/2235 UTC.  The short
lived 10 MeV proton event ended at 19/2255 UTC though flux levels
remained elevated at time of bulletin issue.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be at quiet to minor storm levels with the possibility
of isolated major storm conditions late on day one and through day
two of the period.  Analysis of the full halo CME, on LASCO imagery
(X1/2b flare at 19/0105 UTC from Region 9661), indicated shock
arrival late on day one or early on day two.  A second full halo CME
(X1/2b flare at 19/1630 UTC from Region 9661) is expected to arrive
late on day two of the period.  The greater than 10 MeV proton flux
levels from geosynchronous orbit could remain elevated through first
day of the period.
III.  Event Probabilities 21 Oct-23 Oct
Class M    70/70/70
Class X    15/15/15
Proton     15/15/15
PCAF       Yellow
IV.  Penticton 10.7 cm Flux
Observed           20 Oct 245
Predicted   21 Oct-23 Oct  245/240/235
90 Day Mean        20 Oct 190
V.  Geomagnetic A Indices
Observed Afr/Ap 19 Oct  006/008
Estimated Afr/Ap 20 Oct  ???/???
Predicted Afr/Ap 21 Oct-23 Oct  025/030-030/035-015/025
VI.  Geomagnetic Activity Probabilities 21 Oct-23 Oct
A.  Middle Latitudes
Active                55/55/40
Minor storm           30/30/10
Major-severe storm    05/05/01
B.  High Latitudes
Active                55/55/45
Minor storm           30/30/15
Major-severe storm    10/10/05