Status Report

NOAA SEC Report of Solar-Geophysical Activity 21 Jul 2001

By SpaceRef Editor
July 21, 2001
Filed under , ,
:Product: Report of Solar-Geophysical Activity
:Issued: 2001 Jul 21 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 202 Issued at 2200Z on 21 Jul 2001
IA.  Analysis of Solar Active Regions and Activity from  20/2100Z
to 21/2100Z:  Solar activity has been low. Region 9543 (S23W06)
produced today's largest flare, a C6/Sf at 0508 UTC. Region 9543
continues to be the largest group on the disk and is growing slowly.
Region 9548 (N16E09) also showed growth but was stable. Region 9545
(N09W43) showed newly emerging magnetic flux in the middle of the
old fields, and exhibited occasional plage fluctuations, but no
flare-level activity.
IB.  Solar Activity Forecast:  Solar activity is expected to be
predominantly low. There is, however, a slight chance for an
isolated M-class event.
IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z:
The geomagnetic field was quiet to unsettled. The greater than 2 MeV
electron fluxes attained high levels during the past 24 hours.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be quiet to unsettled for the next three days. There is
a possibility for a small increase in activity on the third day in
response to a small but favorably positioned coronal hole.
III.  Event Probabilities 22 Jul-24 Jul
Class M    25/25/25
Class X    01/01/01
Proton     01/01/01
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           21 Jul 139
Predicted   22 Jul-24 Jul  140/140/135
90 Day Mean        21 Jul 157
V.  Geomagnetic A Indices
Observed Afr/Ap 20 Jul  008/008
Estimated Afr/Ap 21 Jul  005/008
Predicted Afr/Ap 22 Jul-24 Jul  007/008-007/010-012/015
VI.  Geomagnetic Activity Probabilities 22 Jul-24 Jul
A.  Middle Latitudes
Active                20/20/35
Minor storm           10/10/20
Major-severe storm    05/05/05
B.  High Latitudes
Active                25/25/35
Minor storm           10/10/20
Major-severe storm    05/05/10

SpaceRef staff editor.