NOAA SEC Report of Solar-Geophysical Activity 28 Mar 2002

:Product: Report of Solar-Geophysical Activity

:Issued: 2002 Mar 28 2210 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 087 Issued at 2200Z on 28 Mar 2002

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

to 28/2100Z:  Solar activity was at low levels.  The period began

with multiple low level C-class flares that went optically

uncorrelated.  Region 9880 (N09W63) may have been responsible for

several of the minor C-class flares and underwent slight decay late

in the period.  The gamma portion of yesterday’s magnetic

classification is no longer evident.  Region 9885 (N11E69) is

believed responsible for the largest flare during the period,

producing a C7 x-ray flare at 28/1800 UTC.  This region has shown

steady growth in penumbral coverage.  Region 9878 (N09W26) was

unimpressive this period and has been in steady decay, the delta

spot observed yesterday has become two distinct separate spots.

Although less magnetically complex, this region retains a gamma

magnetic signature.  No new regions were numbered today.

IB.  Solar Activity Forecast:  Solar activity is expected to be at

low to moderate levels.  Regions 9880 and 9885 are magnetically

complex enough to produce isolated M-class flare activity.

IIA.  Geophysical Activity Summary 27/2100Z to 28/2100Z:

The geomagnetic field activity levels were at quiet to unsettled

levels.

IIB.  Geophysical Activity Forecast:  The geomagnetic field levels

are expected to be at quiet to unsettled conditions throughout the

forecast period.

III.  Event Probabilities 29 Mar-31 Mar

Class M    45/45/35

Class X    05/05/05

Proton     05/05/05

PCAF       green

IV.  Penticton 10.7 cm Flux

Observed           28 Mar 176

Predicted   29 Mar-31 Mar  170/170/165

90 Day Mean        28 Mar 206

V.  Geomagnetic A Indices

Observed Afr/Ap 27 Mar  003/005

Estimated Afr/Ap 28 Mar  003/005

Predicted Afr/Ap 29 Mar-31 Mar  005/008-006/008-010/010

VI.  Geomagnetic Activity Probabilities 29 Mar-31 Mar

A.  Middle Latitudes

Active                15/15/20

Minor storm           05/05/05

Major-severe storm    01/01/01

B.  High Latitudes

Active                20/20/25

Minor storm           05/05/05

Major-severe storm    02/02/02