Joint USAF/NOAA Report of Solar and Geophysical Activity 21 Aug 2002

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 233 Issued at 2200Z on 21 Aug 2002

IA.  Analysis of Solar Active Regions and Activity from  20/2100Z

to 21/2100Z:  Solar activity has been high.  Region 69 (S08W58)

produced an X1/1b event at 21/0534 UTC with an associated Type II

radio sweep.  This region continues to produce the majority of

C-class and M-class events and maintains its beta-gamma-delta

magnetic configuration.
IB.  Solar Activity Forecast:  Solar activity is expected to be

moderate to high.  Region 69 still posses the potential for an

isolated major flare.
IIA.  Geophysical Activity Summary 20/2100Z to 21/2100Z:

The geomagnetic field has been at unsettled to severe storm

conditions.  The ACE satellite observed an extended period of

southward Bz in the solar wind from 20/2048-21/1247 UTC.
IIB.  Geophysical Activity Forecast:  The geomagnetic field is

expected to be quiet to unsettled.  Isolated active levels are still

possible as a result of the solar activity from Region 69 over the

past several days.
III.  Event Probabilities 22 Aug-24 Aug

Class M    75/75/75

Class X    20/20/20

Proton     10/10/10

PCAF       yellow
IV.  Penticton 10.7 cm Flux

Observed           21 Aug 220

Predicted   22 Aug-24 Aug  220/215/215

90 Day Mean        21 Aug 169
V.  Geomagnetic A Indices

Observed Afr/Ap 20 Aug  016/023

Estimated Afr/Ap 21 Aug  034/035

Predicted Afr/Ap 22 Aug-24 Aug  012/015-012/012-015/015
VI.  Geomagnetic Activity Probabilities 22 Aug-24 Aug

A.  Middle Latitudes

Active                30/30/30

Minor storm           15/15/15

Major-severe storm    05/05/05

B.  High Latitudes

Active                35/35/35

Minor storm           20/20/20

Major-severe storm    10/10/10