NOAA SEC Report of Solar-Geophysical Activity- 6 Feb 2002

:Product: Report of Solar-Geophysical Activity

:Issued: 2002 Feb 06 2210 UT

# 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 037 Issued at 2200Z on 06 Feb 2002

IA.  Analysis of Solar Active Regions and Activity from  05/2100Z

to 06/2100Z:  Solar activity was at moderate levels.  Region 9802

(S13W68) produced an M1.4 flare at 06/1132 UTC.  Region 9816

(S11W58) produced a C8/Sf at 06/0445 UTC with an associated Type II

Radio Sweep (457 km/s).  Region 9802 has shown rapid decay in the

last 24 hours and now has a beta-gamma magnetic configuration with

310 millionths area, 17 spots and an extent of 13 degrees.  Region

9816 also has entered a decay phase.

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

to moderate.  Region 9802, while in a decay phase, still has the

potential for an M-class event.

IIA.  Geophysical Activity Summary 05/2100Z to 06/2100Z:

The geomagnetic field was at unsettled to active levels with one 3

hour period of quiet conditions.  A large coronal hole is centered

at S10W40 and is producing the unsettled to active conditions.  This

coronal hole has an average solar wind speed of 625 km/s over the

last 24 hours.  Average Bz for the last 24 hours was a negative 0 –

5 nT.

IIB.  Geophysical Activity Forecast:  The geomagnetic field is

expected to be at quiet to active levels for the first day of the

forecast period.  Day two and three are expected to return to quiet

to unsettled levels as the coronal hole rotates beyond a

geo-effective position.

III.  Event Probabilities 07 Feb-09 Feb

Class M    55/50/40

Class X    10/05/05

Proton     05/05/01

PCAF       green

IV.  Penticton 10.7 cm Flux

Observed           06 Feb 203

Predicted   07 Feb-09 Feb  205/200/195

90 Day Mean        06 Feb 225

V.  Geomagnetic A Indices

Observed Afr/Ap 05 Feb  015/016

Estimated Afr/Ap 06 Feb  015/016

Predicted Afr/Ap 07 Feb-09 Feb  012/015-010/012-008/010

VI.  Geomagnetic Activity Probabilities 07 Feb-09 Feb

A.  Middle Latitudes

Active                30/20/15

Minor storm           15/10/05

Major-severe storm    01/01/01

B.  High Latitudes

Active                35/25/20

Minor storm           20/15/10

Major-severe storm    01/01/01