NOAA SEC Report of Solar-Geophysical Activity – 21 Mar 2002

:Product: Report of Solar-Geophysical Activity

:Issued: 2002 Mar 21 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 080 Issued at 2200Z on 21 Mar 2002

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

to 21/2100Z:  Solar activity remained at low levels. Region 9866

(S09W84) produced a C-class flare and a few bright surges as it

began to cross the west limb. Regions 9870 (S20W73), 9871 (S18W32)

and 9873 (S18W67) each produced C-class subflares, but were

otherwise unremarkable. New Regions 9879 (N15W50) and 9880 (N08E35)

were numbered.

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

low to moderate levels. There is a fair chance for an isolated,

low-level M-class flare during the period.

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

Geomagnetic field activity was at quiet to unsettled levels. The

greater than 10 MeV proton flux at geosynchronous orbit was enhanced

in the wake of yesterday’s proton event, but gradually decreased

toward background levels.

IIB.  Geophysical Activity Forecast:  Geomagnetic field activity is

forecast to be at unsettled to active levels on 22 March in response

to a partial-halo CME observed on 19 March. Quiet to unsettled

conditions are expected during the rest of the period. There is a

slight chance for a proton flare early in the period from Region

9866 as it rotates out of view.

III.  Event Probabilities 22 Mar-24 Mar

Class M    50/40/40

Class X    05/05/05

Proton     10/05/05

PCAF       green

IV.  Penticton 10.7 cm Flux

Observed           21 Mar 174

Predicted   22 Mar-24 Mar  170/165/165

90 Day Mean        21 Mar 213

V.  Geomagnetic A Indices

Observed Afr/Ap 20 Mar  007/007

Estimated Afr/Ap 21 Mar  006/008

Predicted Afr/Ap 22 Mar-24 Mar  015/015-012/012-010/010

VI.  Geomagnetic Activity Probabilities 22 Mar-24 Mar

A.  Middle Latitudes

Active                30/25/20

Minor storm           20/15/10

Major-severe storm    10/05/05

B.  High Latitudes

Active                35/30/25

Minor storm           25/20/15

Major-severe storm    15/10/05