Joint USAF/NOAA Report of Solar and Geophysical Activity 02 Sep 2007

Product: Report of Solar-Geophysical Activity
Issued: 2007 Sep 02 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 245 Issued at 2200Z on 02 Sep 2007

IA. Analysis of Solar Active Regions and Activity from 01/2100Z to 02/2100Z: Solar activity was very low. There were only three, low-level B-class flares during the last 24 hours.

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

IIA. Geophysical Activity Summary 01/2100Z to 02/2100Z: The geomagnetic field was mostly unsettled to active with some isolated minor storm periods. The increase in activity corresponds to a high speed solar wind stream associated with a favorably positioned coronal hole. Real-time solar wind speeds increased up to 600-650 km/s early in the period, and remained at that level throughout the day. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be mostly unsettled with isolated active periods during the next 24 hours (03 September) as the current solar wind stream persists. Conditions should decline to predominantly quiet for the second and third days (04-05 September).

III. Event Probabilities 03 Sep-05 Sep

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

IV. Penticton 10.7 cm Flux

• Observed 02 Sep 069
• Predicted 03 Sep-05 Sep 069/069/069
• 90 Day Mean 02 Sep 071

V. Geomagnetic A Indices

• Observed Afr/Ap 01 Sep 009/011
• Estimated Afr/Ap 02 Sep 018/020
• Predicted Afr/Ap 03 Sep-05 Sep 010/015-005/005-005/005

VI. Geomagnetic Activity Probabilities 03 Sep-05 Sep

A. Middle Latitudes

• Active 35/15/15
• Minor storm 15/05/05
• Major-severe storm 05/01/01

B. High Latitudes

• Active 35/15/15
• Minor storm 15/05/05
• Major-severe storm 05/01/01