Joint USAF/NOAA Report of Solar and Geophysical Activity 12 Sep 2008

Product: Report of Solar-Geophysical Activity
Issued: 2008 Sep 12 2200 UTC
Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Weather Prediction Center and the U.S. Air Force.

Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 256 Issued at 2200Z on 12 Sep 2008

IA. Analysis of Solar Active Regions and Activity from 11/2100Z to 12/2100Z: Solar activity was very low. The visible solar disk was spotless.

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

IIA. Geophysical Activity Summary 11/2100Z to 12/2100Z: The geomagnetic field was quiet. The greater than 2 MeV electron flux at geosynchronous orbit was at high levels today.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels for 13 September. Predominately unsettled conditions with isolated active levels are expected for 14 September. Unsettled to active conditions with isolated minor storming are expected for 15 September. The increase in activity is due to a recurrent coronal hole high speed stream.

III. Event Probabilities 13 Sep-15 Sep

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

IV. Penticton 10.7 cm Flux

• Observed 12 Sep 066
• Predicted 13 Sep-15 Sep 066/066/066
• 90 Day Mean 12 Sep 066

V. Geomagnetic A Indices

• Observed Afr/Ap 11 Sep 001/002
• Estimated Afr/Ap 12 Sep 002/005
• Predicted Afr/Ap 13 Sep-15 Sep 005/008-010/015-015/020

VI. Geomagnetic Activity Probabilities 13 Sep-15 Sep

A. Middle Latitudes

• Active 10/25/35
• Minor storm 01/05/10
• Major-severe storm 01/01/05

B. High Latitudes

• Active 25/30/40
• Minor storm 05/10/20
• Major-severe storm 01/01/10