Joint USAF/NOAA Report of Solar and Geophysical Activity 10 Aug 2008

Product: Report of Solar-Geophysical Activity
Issued: 2008 Aug 10 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 223 Issued at 2200Z on 10 Aug 2008

IA. Analysis of Solar Active Regions and Activity from 09/2100Z to 10/2100Z: Solar activity was very low. The visible solar disk remains spotless. No flares were observed during the past 24 hours.

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

IIA. Geophysical Activity Summary 09/2100Z to 10/2100Z: The geomagnetic field ranged from quiet to minor storm conditions. Observations measured at the ACE spacecraft show a continued influence of the recurrent coronal hole high speed solar wind stream. Solar wind speed has averaged around 630 km/s with Bz fluctuations from +4 nT to -7 nT.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled conditions for day one (11 August) of the forecast. Predominately quiet levels are expected for days two and three (12-13 August) as the high speed stream becomes less geoeffective.

III. Event Probabilities 11 Aug-13 Aug

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

IV. Penticton 10.7 cm Flux

• Observed 10 Aug 066
• Predicted 11 Aug-13 Aug 066/066/066
• 90 Day Mean 10 Aug 067

V. Geomagnetic A Indices

• Observed Afr/Ap 09 Aug 016/018
• Estimated Afr/Ap 10 Aug 010/010
• Predicted Afr/Ap 11 Aug-13 Aug 007/008-005/005-005/005

VI. Geomagnetic Activity Probabilities 11 Aug-13 Aug

A. Middle Latitudes

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

B. High Latitudes

• Active 20/05/05
• Minor storm 05/01/01
• Major-severe storm 01/01/01