Joint USAF/NOAA Report of Solar and Geophysical Activity 19 Aug 2004

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.

Updated 2004 Aug 19 2200 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 232 Issued at 2200Z on 19 Aug 2004

IA. Analysis of Solar Active Regions and Activity from 18/2100Z
to 19/2100Z: Solar activity has been moderate. Region 656
(S13,L=87) continues to produce M-class flares from the west limb:
an M3.0 at 19/0701 UTC and an M2.1 at 1351 UTC. Region 661 (N09W06)
is stable in size and magnetic conplexity, maintaining its
beta-gamma configuration. A CME was observed on LASCO imagery from
the X1.8 flare reported yesterday, although the CME was not directed
toward Earth. New Region 663 (N08E75) was numbered today.

IB. Solar Activity Forecast: Solar activity is expected to be low
to moderate. Lingering flare activity from Region 656 is still
possible for another day. Region 661 is capable of producing
isolated M-class flares.

IIA. Geophysical Activity Summary 18/2100Z to 19/2100Z:
The geomagnetic field has been quiet to unsettled.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled for the next three days, with
isolated active conditions possible on 20 August.

III. Event Probabilities 20 Aug-22 Aug

• Class M 30/20/20
• Class X 10/05/01
• Proton 05/01/01
• PCAF green

IV. Penticton 10.7 cm Flux

• Observed 19 Aug 121
• Predicted 20 Aug-22 Aug 115/110/105
• 90 Day Mean 19 Aug 109

V. Geomagnetic A Indices

• Observed Afr/Ap 18 Aug 010/013
• Estimated Afr/Ap 19 Aug 008/013
• Predicted Afr/Ap 20 Aug-22 Aug 008/015-005/012-005/010

VI. Geomagnetic Activity Probabilities 20 Aug-22 Aug

A. Middle Latitudes

• Active 30/20/20
• Minor storm 05/01/01
• Major-severe storm 01/01/01

B. High Latitudes

• Active 40/30/30
• Minor storm 10/05/05
• Major-severe storm 01/01/01