Joint USAF/NOAA Report of Solar and Geophysical Activity 08 Sep 2004

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

Updated 2004 Sep 08 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 252 Issued at 2200Z on 08 Sep 2004

IA. Analysis of Solar Active Regions and Activity from 07/2100Z
to 08/2100Z: Solar activity has been low. A C1.5 flare occurred at
0110 UTC and was observed by SXI on the east limb at N05. A C1.0
flare was observed at 2002 UTC from Region 669 (S05W09). Region 669
also produced a B9.0 at 0349 UTC and a B9.7 at 1458 UTC. A 20
degree filament disappeared from N01W35 between 1324 UTC and 1519
UTC, but there was no obvious CME that could be associated.

IB. Solar Activity Forecast: Solar activity is expected to be low.
There is a slight chance for an isolated M class flare.

IIA. Geophysical Activity Summary 07/2100Z to 08/2100Z:
The geomagnetic field has been quiet to unsettled with an isolated
active period from 0600 to 0900 UTC. Solar wind data from ACE has
indicated a decrease in solar wind speed during the past 24 hours
from approximately 440 km/s to 380 km/s.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled for the next three days (09-11
September).

III. Event Probabilities 09 Sep-11 Sep

• Class M 15/15/15
• Class X 01/01/01
• Proton 01/01/01
• PCAF Green

IV. Penticton 10.7 cm Flux

• Observed 08 Sep 125
• Predicted 09 Sep-11 Sep 130/135/140
• 90 Day Mean 08 Sep 111

V. Geomagnetic A Indices

• Observed Afr/Ap 07 Sep 011/016
• Estimated Afr/Ap 08 Sep 008/010
• Predicted Afr/Ap 09 Sep-11 Sep 006/010-006/008-006/008

VI. Geomagnetic Activity Probabilities 09 Sep-11 Sep

A. Middle Latitudes

• Active 25/25/25
• Minor storm 05/05/05
• Major-severe storm 05/05/05

B. High Latitudes

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