Joint USAF/NOAA Report of Solar and Geophysical Activity 28 Aug 2002

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 240 Issued at 2200Z on 28 Aug 2002

IA.  Analysis of Solar Active Regions and Activity from  27/2100Z

to 28/2100Z:  Solar activity was at moderate levels.  Region 90

(S04E20) produced an M4/Sf flare at 28/1859 UTC that had an

associated Type II radio sweep with an estimated shock velocity of

736 km/s.  A significant Type four radio sweep and a Tenflare of 930

pfu were also associated with this flare.  Region 83 (S18W84), which

is currently exiting the disk,  produced an M1 flare (correlated

using SOHO/EIT imagery) at 28/1658 UTC.  Region 87 (S08W07) showed

growth during the period as a delta magnetic spot became apparent in

the southeast portion of the spot group.  Region 85 (S08W50) showed

a slight growth in penumbral coverage although remained fairly

quiescent during the period.  No new regions were numbered today.
IB.  Solar Activity Forecast:  Solar activity is expected to be at

low to moderate levels.  Region 87 has the potential to produce

M-class activity.
IIA.  Geophysical Activity Summary 27/2100Z to 28/2100Z:

The geomagnetic field was at quiet to unsettled levels.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is

expected to be quiet to unsettled throughout the period.
III.  Event Probabilities 29 Aug-31 Aug

Class M    45/45/45

Class X    01/01/01

Proton     01/01/01

PCAF       green
IV.  Penticton 10.7 cm Flux

Observed           28 Aug 163

Predicted   29 Aug-31 Aug  160/150/145

90 Day Mean        28 Aug 169
V.  Geomagnetic A Indices

Observed Afr/Ap 27 Aug  014/015

Estimated Afr/Ap 28 Aug  008/008

Predicted Afr/Ap 29 Aug-31 Aug  008/008-008/008-008/008
VI.  Geomagnetic Activity Probabilities 29 Aug-31 Aug

A.  Middle Latitudes

Active                15/15/15

Minor storm           05/05/05

Major-severe storm    01/01/01

B.  High Latitudes

Active                20/20/20

Minor storm           10/10/10

Major-severe storm    01/01/01