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

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2004 Sep 27 2210 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 271 Issued at 2200Z on 27 Sep 2004

IA. Analysis of Solar Active Regions and Activity from 26/2100Z
to 27/2100Z: Solar activity was very low. Today’s activity
consisted of a few low level B-class flares. An 8 degree filament
near N08E40 disappeared sometime in the last 24 hours.

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

IIA. Geophysical Activity Summary 26/2100Z to 27/2100Z:
The geomagnetic field was mostly quiet. The greater than 2 MeV
electrons at geosynchronous orbit reached high levels today.

IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be quiet to unsettled.

III. Event Probabilities 28 Sep-30 Sep
Class M 01/01/01
Class X 01/01/01
Proton 01/01/01
PCAF green

IV. Penticton 10.7 cm Flux
Observed 27 Sep 090
Predicted 28 Sep-30 Sep 090/095/095
90 Day Mean 27 Sep 111

V. Geomagnetic A Indices
Observed Afr/Ap 26 Sep 002/004
Estimated Afr/Ap 27 Sep 005/005
Predicted Afr/Ap 28 Sep-30 Sep 005/008-005/008-005/005

VI. Geomagnetic Activity Probabilities 28 Sep-30 Sep
A. Middle Latitudes
Active 20/20/20
Minor storm 10/10/10
Major-severe storm 05/05/05
B. High Latitudes
Active 30/30/30
Minor storm 10/10/10
Major-severe storm 05/05/05