NOAA SEC Report of Solar-Geophysical Activity 19 Mar 2002

:Product: Report of Solar-Geophysical Activity

:Issued: 2002 Mar 19 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 078 Issued at 2200Z on 19 Mar 2002

IA.  Analysis of Solar Active Regions and Activity from  18/2100Z

to 19/2100Z:  Solar activity was moderate.  Region 9866 (S10W59)

produced a long duration  M1/1f flare at 19/1144 UTC.  Two partial

halo CMEs in rapid succession occurred along with this event, with

an estimated plane of sky speed for the combined ejecta in the range

of 700-750 km/s.  Region 9866 has simplified to a beta-gamma

magnetic configuration.  Two new regions were numbered today:

Region 9874 (N18E21) and Region 9875 (S18E63).

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

moderate.  Region 9866 and Region 9871 have the potential for

M-class events.  There is a slight possibility for an isolated

X-class or proton event.

IIA.  Geophysical Activity Summary 18/2100Z to 19/2100Z:

The geomagnetic field was at quiet to minor storm levels  Minor storm

levels were observed early in the day, due to a three hour period of

sustained southward Bz during 0200-0500 UTC.  The greater than 10

MeV proton event remains in progress, with a maximum flux of 53 pfu

observed at 19/0650 UTC.

IIB.  Geophysical Activity Forecast:  The geomagnetic field is

expected to be quiet to active.  Active conditions are expected on

day one from effects of the CME on 18 March.  Actiment is expected

to subside during day two.  By day three, effects from the CME

activity discussed in section 1A above are expected to result in

predominantly active conditions.

III.  Event Probabilities 20 Mar-22 Mar

Class M    55/55/55

Class X    10/10/10

Proton     10/10/10

PCAF       yellow

IV.  Penticton 10.7 cm Flux

Observed           19 Mar 175

Predicted   20 Mar-22 Mar  175/175/170

90 Day Mean        19 Mar 214

V.  Geomagnetic A Indices

Observed Afr/Ap 18 Mar  009/012

Estimated Afr/Ap 19 Mar  012/015

Predicted Afr/Ap 20 Mar-22 Mar  020/020-012/010-015/015

VI.  Geomagnetic Activity Probabilities 20 Mar-22 Mar

A.  Middle Latitudes

Active                30/25/35

Minor storm           20/15/25

Major-severe storm    10/05/10

B.  High Latitudes

Active                35/30/35

Minor storm           25/20/25

Major-severe storm    15/10/15