Joint USAF/NOAA Report of Solar and Geophysical Activity 10 Aug 2002

:Product: Report of Solar-Geophysical Activity

:Issued: 2002 Aug 10 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 222 Issued at 2200Z on 10 Aug 2002

IA.  Analysis of Solar Active Regions and Activity from  09/2100Z

to 10/2100Z:  Solar activity was low.  No optical reports were

received for the minor C-class flare activity observed throughout

the period.  However, a large filament located near central meridian

at about N30 appeared to dissipate early in the period, in

association with a subsequent CME evident in LASCO C2 imagery at

about 09/2330 UTC.  This CME appears directed largely north of the

ecliptic.  Two new regions rotated into view on the east limb and

were numbered today:  Region 67 (N09E71) and Region 68 (S07E71).

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

predominantly low.  Region 61 (N08W15) is still a moderately large

region which could produce isolated M-class activity during the

period.

IIA.  Geophysical Activity Summary 09/2100Z to 10/2100Z:

The geomagnetic field was at unsettled to minor storm levels early in

the period, then at quiet to unsettled levels for the remainder.

The isolated minor storm period was observed at higher latitudes

during 10/0300-0600 UTC, in probable association with a sustained

period of southward Bz during that time.

IIB.  Geophysical Activity Forecast:  The geomagnetic field is

expected to be mainly quiet to unsettled for the first day of the

forecast period.  Isolated active periods are possible on day two

and three, due to expected coronal hole effects, or possibly some

flanking shock passage effects from the CME activity described in

section 1A above.

III.  Event Probabilities 11 Aug-13 Aug

Class M    25/25/25

Class X    01/01/01

Proton     01/01/01

PCAF       green

IV.  Penticton 10.7 cm Flux

Observed           10 Aug 148

Predicted   11 Aug-13 Aug  145/150/150

90 Day Mean        10 Aug 164

V.  Geomagnetic A Indices

Observed Afr/Ap 09 Aug  009/015

Estimated Afr/Ap 10 Aug  009/015

Predicted Afr/Ap 11 Aug-13 Aug  008/010-012/012-015/015

VI.  Geomagnetic Activity Probabilities 11 Aug-13 Aug

A.  Middle Latitudes

Active                15/25/30

Minor storm           05/10/10

Major-severe storm    01/01/01

B.  High Latitudes

Active                20/30/35

Minor storm           05/10/10

Major-severe storm    01/01/01