NOAA SEC Report of Solar-Geophysical Activity 21 Aug 2001

:Product: Report of Solar-Geophysical Activity
:Issued: 2001 Aug 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 233 Issued at 2200Z on 21 Aug 2001
IA.  Analysis of Solar Active Regions and Activity from  20/2100Z
to 21/2100Z:  Solar activity remained low. Region 9585 (N15E11)
produced isolated subflares, none of which were associated with
significant X-ray emission. New Region 9591 (S18E71) rotated into
view. It was the likely source for a bright surge near SE19 at
21/1050 UTC. A filament erupted from the southwest quadrant around
mid-period. The eruption was associated with a long-duration C2
X-ray event that peaked at 21/1303 UTC and a coronal mass ejection
that did not appear to be Earth directed.
IB.  Solar Activity Forecast:  Solar activity is expected to be at
low to moderate levels. There will be a fair chance for an isolated
M-class flare during the period.
IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z:
Geomagnetic field activity ranged from quiet to active levels.
Activity increased to unsettled to active levels after 21/0900 UTC.
The greater than 10 MeV proton flux remained slightly enhanced and
gradually decreased toward background in the wake of the proton
event of 16 - 18 August.
IIB.  Geophysical Activity Forecast:  Geomagnetic field activity is
expected to be at quiet to unsettled levels during most of the
period.
III.  Event Probabilities 22 Aug-24 Aug
Class M    30/30/30
Class X    05/05/05
Proton     01/01/05
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           21 Aug 160
Predicted   22 Aug-24 Aug  165/170/175
90 Day Mean        21 Aug 152
V.  Geomagnetic A Indices
Observed Afr/Ap 20 Aug  006/010
Estimated Afr/Ap 21 Aug  014/016
Predicted Afr/Ap 22 Aug-24 Aug  012/010-010/010-012/012
VI.  Geomagnetic Activity Probabilities 22 Aug-24 Aug
A.  Middle Latitudes
Active                25/20/20
Minor storm           10/10/10
Major-severe storm    01/01/01
B.  High Latitudes
Active                30/25/25
Minor storm           15/15/15
Major-severe storm    01/01/01