Joint USAF/NOAA Report of Solar and Geophysical Activity 05 Sep 2008

Product: Report of Solar-Geophysical Activity
Issued: 2008 Sep 05 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 249 Issued at 2200Z on 05 Sep 2008

IA. Analysis of Solar Active Regions and Activity from 04/2100Z to 05/2100Z: Solar activity was very low. No flares occurred during the past 24 hours and the solar disk continues to be spotless.

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

IIA. Geophysical Activity Summary 04/2100Z to 05/2100Z: The geomagnetic field was predominantly quiet during the past 24 hours, with the exception of an unsettled period from 0300-0600Z. Solar wind observations at ACE show a generally declining trend in the solar wind velocity with values around 500 km/s at the end of the period. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels during the past 24 hours.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled for the next two days (06-07 September). Activity is expected to decrease to quiet levels for the third day (08 September).

III. Event Probabilities 06 Sep-08 Sep

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

IV. Penticton 10.7 cm Flux

• Observed 05 Sep 065
• Predicted 06 Sep-08 Sep 066/066/066
• 90 Day Mean 05 Sep 066

V. Geomagnetic A Indices

• Observed Afr/Ap 04 Sep 017/033
• Estimated Afr/Ap 05 Sep 007/010
• Predicted Afr/Ap 06 Sep-08 Sep 007/010-005/008-005/005

VI. Geomagnetic Activity Probabilities 06 Sep-08 Sep

A. Middle Latitudes

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

B. High Latitudes

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