NOAA SEC Report of Solar-Geophysical Activity 28 Mar 2001

:Product: Report of Solar-Geophysical Activity
:Issued: 2001 Mar 28 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 087 Issued at 2200Z on 28 Mar 2001
IA.  Analysis of Solar Active Regions and Activity from  27/2100Z
to 28/2100Z:  Solar activity was moderate.  Region 9393 (N13E00) once
again produced the most activity with four M-class events during the
period.  The first was an M1/Sf at 28/0158Z, the second was an M1/Sn
at 28/0947Z, the third was an M4/Sf at 28/1240Z and the fourth was
an M1/1f at 28/1909Z.   Regions 9403 (S13E36) and 9397 (S09E19)
produced upper C-class level events.  Region 9393 continued growing
and currently covers an area of over 2200 millionths in white light.
The region is also maintaining a very complex beta-gamma-delta
magnetic configuration.  Four new regions were numbered today,
Region 9405 (S13W20), Region 9406 (N25E67), 9407 (N11E64), and 9408
(S08E38).
IB.  Solar Activity Forecast:  Solar activity is expected to be
moderate to high.  Region 9393 has the best potential to produce a
major flare.
IIA.  Geophysical Activity Summary 27/2100Z to 28/2100Z:
The geomagnetic field was quiet to major storm.  Minor to major storm
conditions were observed from 28/0900Z to 28/1500Z.  An
earth-directed full halo CME was seen in LASCO/SOHO imagery.  The
halo occurred at approximately 28/1300Z and was associated with the
M4/Sf event in Region 9393.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is
expected to be predominately quiet to unsettled with possible
isolated active conditions on the first day.  Conditions are
expected to increase during the middle of the period reaching minor
to major storm levels due to a CME passage.  Conditions are expected
to decrease towards the end of the period to unsettled to active
levels.  There is the possiblilty for a proton event if Region 9393
produces a major flare event.
III.  Event Probabilities 29 Mar-31 Mar
Class M    75/75/75
Class X    20/20/20
Proton     15/15/15
PCAF       yellow
IV.  Penticton 10.7 cm Flux
Observed           28 Mar 274
Predicted   29 Mar-31 Mar  270/265/255
90 Day Mean        28 Mar 162
V.  Geomagnetic A Indices
Observed Afr/Ap 27 Mar  016/018
Estimated Afr/Ap 28 Mar  024/030
Predicted Afr/Ap 29 Mar-31 Mar  014/015-030/030-020/020
VI.  Geomagnetic Activity Probabilities 29 Mar-31 Mar
A.  Middle Latitudes
Active                25/30/40
Minor storm           10/40/30
Major-severe storm    01/15/10
B.  High Latitudes
Active                30/20/30
Minor storm           15/45/40
Major-severe storm    05/25/20