Joint USAF/NOAA Report of Solar and Geophysical Activity 27 Aug 2004

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

Updated 2004 Aug 27 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 240 Issued at 2200Z on 27 Aug 2004

IA. Analysis of Solar Active Regions and Activity from 26/2100Z
to 27/2100Z: Solar activity decreased to very low levels today.
Flares were limited to very minor B-class events today. Region 663
(N10W27) showed a little growth in magnetic complexity yet spot area
decreased over the period. Region 664 (S11W58) decayed into an Hsx
alpha spot group since yesterday. An eruptive prominence at S02 on
the west solar limb occurred at 27/0906Z through 27/0931Z. No new
regions were numbered today.

IB. Solar Activity Forecast: Solar activity is expected to be at
very low to low levels. Region 663 has the potential to produce
isolated low level C-class flare activity.

IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z:
The geomagnetic field was at quiet to unsettled levels today.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at quiet to unsettled levels throughout the period.

III. Event Probabilities 28 Aug-30 Aug

• Class M 05/05/05
• Class X 01/01/01
• Proton 01/01/01
• PCAF green

IV. Penticton 10.7 cm Flux

• Observed 27 Aug 091
• Predicted 28 Aug-30 Aug 090/085/085
• 90 Day Mean 27 Aug 110

V. Geomagnetic A Indices

• Observed Afr/Ap 26 Aug 004/007
• Estimated Afr/Ap 27 Aug 005/008
• Predicted Afr/Ap 28 Aug-30 Aug 006/008-004/008-004/005

VI. Geomagnetic Activity Probabilities 28 Aug-30 Aug

A. Middle Latitudes

• Active 15/10/10
• Minor storm 01/01/01
• Major-severe storm 01/01/01

B. High Latitudes

• Active 15/15/15
• Minor storm 05/05/01
• Major-severe storm 01/01/01