Status Report

NOAA SEC Report of Solar-Geophysical Activity 4 Nov 2001

By SpaceRef Editor
November 4, 2001
Filed under , ,
:Product: Report of Solar-Geophysical Activity
:Issued: 2001 Nov 04 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 308 Issued at 2200Z on 04 Nov 2001
IA.  Analysis of Solar Active Regions and Activity from  03/2100Z
to 04/2100Z:  Solar activity has been high. Region 9684 (N06W27)
produced an X1/3b flare beginning at 1603 UTC, maximum at 1620 UTC,
and ending at 1647 UTC. The event was accompanied by strong radio
bursts, a type II sweep, and a type IV sweep. A CME was observed to
enter the C2 field of view during the flare, with the leading edge
just visible at 1635 UTC. The front edge moved quickly across C2 and
exited somewhere between 1655 UTC and 1705 UTC. Region 9684 has
grown and the leader and trailer spots merged during the past 24
hours, making the region a beta-gamma-delta group. Region 9687
(S20E35) continues to be a complex, beta-gamma group and produced a
few C-class subflares. Region 9682 (N13W64) is still the largest
group on the disk but could only muster a couple of subflares. A 10
degree filament just west of Region 9684 disappeared sometime
between 03/2208 UTC and 04/0629 UTC.
IB.  Solar Activity Forecast:  Solar activity is expected to be
moderate to high. M-class events are likely to occur during the next
three days. There is a fair chance for an additional major flare
from Region 9684, especially if new magnetic flux continues to
emerge. Regions 9682 and 9687 also continue to pose a slight threat
for major flare activity.
IIA.  Geophysical Activity Summary 03/2100Z to 04/2100Z:
The geomagnetic field was quiet to unsettled during the past 24
hours. A greater than 100 MeV proton event began at 1650 UTC,
shortly after today's X-class flare. Flux levels rose quickly
initially, but began to level off around 1800 UTC, although they are
still climbing slowly. The maximum 100 MeV flux observed so far is
56 pfu at 2035 UTC. A greater than 10 MeV proton event began at 1705
UTC. This event also seems to be leveling off, and the maximum flux
observed so far is 1180 pfu at 2040 UTC.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be unsettled to slightly active tomorrow. Major storm
conditions are likely to follow the arrival of a shock from today's
solar event, sometime early on the 2nd day (06 November). The
disturbance is expected to last for about 24 hours, and a decrease
to mostly active conditions should occur on the third day. Today's
greater than 100 MeV proton event is expected to continue for the
next 12 hours. The greater than 10 MeV proton event should continue
tomorrow, and is likely to get an enhancement of flux levels on the
second day with the arrival of the interplanetary shock from today's
solar event.
III.  Event Probabilities 05 Nov-07 Nov
Class M    80/80/80
Class X    25/25/25
Proton     99/80/25
PCAF       in progress
IV.  Penticton 10.7 cm Flux
Observed           04 Nov 227
Predicted   05 Nov-07 Nov  220/215/210
90 Day Mean        04 Nov 206
V.  Geomagnetic A Indices
Observed Afr/Ap 03 Nov  001/003
Estimated Afr/Ap 04 Nov  007/008
Predicted Afr/Ap 05 Nov-07 Nov  015/015-050/050-025/025
VI.  Geomagnetic Activity Probabilities 05 Nov-07 Nov
A.  Middle Latitudes
Active                25/10/20
Minor storm           15/15/35
Major-severe storm    15/75/35
B.  High Latitudes
Active                25/05/15
Minor storm           15/10/30
Major-severe storm    15/80/35

SpaceRef staff editor.