Joint USAF/NOAA Report of Solar and Geophysical Activity 21 Sep 2005

Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2005 Sep 21 2204 UTC

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 264 Issued at 2200Z on 21 Sep 2005

IA. Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: Solar activity was very low. Region 810 (N08E21) is the only region with spots on the visible disk.

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

IIA. Geophysical Activity Summary 20/2100Z to 21/2100Z: The geomagnetic field was quiet to unsettled. The greater then 2 MeV electron flux at geosynchronous orbit was high again today.

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

III. Event Probabilities 22 Sep-24 Sep

• Class M 10/10/10
• Class X 01/01/01
• Proton 01/01/01
• PCAF green

IV. Penticton 10.7 cm Flux

• Observed 21 Sep 086
• Predicted 22 Sep-24 Sep 085/080/080
• 90 Day Mean 21 Sep 093

V. Geomagnetic A Indices

• Observed Afr/Ap 20 Sep 003/006
• Estimated Afr/Ap 21 Sep 003/012
• Predicted Afr/Ap 22 Sep-24 Sep 005/010-005/010-005/010

VI. Geomagnetic Activity Probabilities 22 Sep-24 Sep

A. Middle Latitudes

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

B. High Latitudes

• Active 20/20/20
• Minor storm 10/10/10
• Major-severe storm 05/05/05