NOAA SEC Report of Solar-Geophysical Activity 25 Mar 2002

:Product: Report of Solar-Geophysical Activity

:Issued: 2002 Mar 25 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 084 Issued at 2200Z on 25 Mar 2002

IA.  Analysis of Solar Active Regions and Activity from  24/2100Z

to 25/2100Z:  Solar activity was low. Region 9878 (N08E15) produced

the two largest events of the period – a C6/Sf at 25/1039Z and a C9

flare at 25/2008Z. No significant changes were noted in this

moderately complex beta-gamma spot group. Regions 9880 (N08W22) and

9881 (S03W48) have shown some growth this period, but remain

relatively stable.

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

to moderate. Region 9878 has the potential to produce isolated

M-class flares. Expect minor C-class flares from Regions 9876

(S15E05), 9880, and 9881.

IIA.  Geophysical Activity Summary 24/2100Z to 25/2100Z:

The geomagnetic field was quiet to unsettled. The period began in a

disturbed state in the waning stages of yesterday’s major

geomagnetic storm. Another interplanetary shock was observed at ACE

at 25/0058Z. The field remained quiet to unsettled following this

shock as Bz remained northward for the duration of this weak

transient passage.

IIB.  Geophysical Activity Forecast:  The geomagnetic field is

expected to continue at quiet to unsettled levels with isolated

active periods.

III.  Event Probabilities 26 Mar-28 Mar

Class M    40/40/40

Class X    05/05/05

Proton     05/05/05

PCAF       green

IV.  Penticton 10.7 cm Flux

Observed           25 Mar 170

Predicted   26 Mar-28 Mar  170/170/170

90 Day Mean        25 Mar 209

V.  Geomagnetic A Indices

Observed Afr/Ap 24 Mar  029/047

Estimated Afr/Ap 25 Mar  010/015

Predicted Afr/Ap 26 Mar-28 Mar  010/010-010/010-005/005

VI.  Geomagnetic Activity Probabilities 26 Mar-28 Mar

A.  Middle Latitudes

Active                40/30/25

Minor storm           15/10/10

Major-severe storm    05/01/01

B.  High Latitudes

Active                45/35/30

Minor storm           20/15/15

Major-severe storm    05/05/05