Joint USAF/NOAA Report of Solar and Geophysical Activity 21 Sep 2006

Product: Report of Solar-Geophysical Activity
Issued: 2006 Sep 21 2200 UTC
Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 264 Issued at 2200Z on 21 Sep 2006

IA. Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: Solar activity was very low. Region 910 (S09E10) remains the only sunspot group on the visible disk.

IB. Solar Activity Forecast: Solar activity is expected to continue at very low levels.

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

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet levels on 22 September. Unsettled to active conditions with isolated minor storm periods are possible on 23 September due to a favorably positioned coronal hole high speed stream. Quiet to unsettled conditions are expected to return for 24 September.

III. Event Probabilities 22 Sep-24 Sep

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

IV. Penticton 10.7 cm Flux

• Observed 21 Sep 071
• Predicted 22 Sep-24 Sep 070/070/070
• 90 Day Mean 21 Sep 077

V. Geomagnetic A Indices

• Observed Afr/Ap 20 Sep 003/005
• Estimated Afr/Ap 21 Sep 005/005
• Predicted Afr/Ap 22 Sep-24 Sep 005/005-015/020-010/012

VI. Geomagnetic Activity Probabilities 22 Sep-24 Sep A. Middle Latitudes

• Active 10/40/30
• Minor storm 01/15/10
• Major-severe storm 01/05/05

B. High Latitudes

• Active 15/50/40
• Minor storm 01/20/15
• Major-severe storm 01/10/05