:Product: 20010513RSGA.txt
:Issued: 2001 May 13 2200 UTC
# 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 133 Issued at 2200Z on 13 May 2001
IA.  Analysis of Solar Active Regions and Activity from  12/2100Z
to 13/2100Z:  Solar activity increased to moderate levels. Region
9455 (S18W11) produced two M-class flares early in the period. The
first was an M3/1b at 12/2335 UTC with an associated 230 SFU
Tenflare and Type IV radio sweep. The second was an M3/Sn at 13/0304
UTC associated with a 220 SFU Tenflare and Type II and IV radio
sweeps. Coronal mass ejections followed both flares, but the bulk of
the mass appeared to be directed southward. Region 9455 remained a
moderate-sized sunspot group with a mix of polarities evident within
its interior spots. Region 9454 (N12E32) remained the largest spot
on the disk at around 400 millionths, but was relatively inactive.
It showed a weak mixing of polarities in the vicinity of its trailer
spots. Minor spot development was noted within Region 9451 (S22W39),
which produced an isolated subflare late in the period. New Region
9457 (S19E03) was numbered.
IB.  Solar Activity Forecast:  Solar activity is expected to be at
low to moderate levels with a fair chance for isolated M-class
flares from Region 9455. There is also a slight chance for an
isolated M-class flare from Region 9454.
IIA.  Geophysical Activity Summary 12/2100Z to 13/2100Z:
Geomagnetic field activity ranged from unsettled to minor storm
levels. Active to minor storm levels occurred until 13/0600 UTC,
followed by mostly unsettled conditions. The greater than 2 MeV
electron flux reached high levels during the period.
IIB.  Geophysical Activity Forecast:  Geomagnetic field activity is
expected to be at unsettled to active levels during the period. The
greater than 2 MeV electron flux may reach high levels during the
period.
III.  Event Probabilities 14 May-16 May
Class M    40/40/40
Class X    05/05/05
Proton     05/05/05
PCAF       green
IV.  Penticton 10.7 cm Flux
Observed           13 May 139
Predicted   14 May-16 May  145/150/160
90 Day Mean        13 May 167
V.  Geomagnetic A Indices
Observed Afr/Ap 12 May  020/034
Estimated Afr/Ap 13 May  020/020
Predicted Afr/Ap 14 May-16 May  015/015-015/012-015/020
VI.  Geomagnetic Activity Probabilities 14 May-16 May
A.  Middle Latitudes
Active                30/30/30
Minor storm           10/10/10
Major-severe storm    05/05/05
B.  High Latitudes
Active                40/40/40
Minor storm           15/15/15
Major-severe storm    10/10/10