NOAA/USAF Report of Solar-Geophysical Activity 26 October 2000

:Product: Report of Solar-Geophysical Activity
:Issued: 2000 Oct 26 2200 UT
# 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 300 Issued at 2200Z on 26 Oct 2000
IA.  Analysis of Solar Active Regions and Activity from  25/2100Z
to 26/2100Z:  Solar activity remained low. Region 9209 (S24E59)
produced a C8/1n flare at 1611 UTC, the largest event of the period.
It also had other, smaller C-class flares. The other area of
activity was the northwest limb, where a C6/sf erupted from a swath
of spotless plage near N17W77. That flare occurred at 1137 UTC. One
new region, 9210 (S30E74) rotated into view.
IB.  Solar Activity Forecast:  Solar activity is expected to be low
to moderate. Region 9209 may produce an isolated M-class event
during the next three days.
IIA.  Geophysical Activity Summary 25/2100Z to 26/2100Z:
The geomagnetic field was quiet to unsettled. A proton event at
greater than 10 MeV began at 0040 UTC, reached a maximum of 15 pfu
at 0340 UTC, and ended at 1000 UTC. This activity is related to the
CME off the west limb near midday on the 25th.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to persist at quiet to unsettled for the next 36-48 hours.
A mild disturbance from yesterday's halo CME is anticipated to begin
late on the 28th. Active conditions are possible through the end of
the period as the magnetosphere takes an oblique hit from the solar
ejection.
III.  Event Probabilities 27 Oct-29 Oct
Class M    40/40/40
Class X    01/01/01
Proton     01/01/01
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           26 Oct 171
Predicted   27 Oct-29 Oct  175/175/180
90 Day Mean        26 Oct 169
V.  Geomagnetic A Indices
Observed Afr/Ap 25 Oct  009/008
Estimated Afr/Ap 26 Oct  010/010
Predicted Afr/Ap 27 Oct-29 Oct  010/010-015/015-015/015
VI.  Geomagnetic Activity Probabilities 27 Oct-29 Oct
A.  Middle Latitudes
Active                20/30/30
Minor storm           05/10/10
Major-severe storm    01/05/05
B.  High Latitudes
Active                25/40/40
Minor storm           05/15/15
Major-severe storm    01/05/05