Joint USAF/NOAA Report of Solar and Geophysical Activity 21 Aug 2008

Product: Report of Solar-Geophysical Activity
Issued: 2008 Aug 21 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 234 Issued at 2200Z on 21 Aug 2008

IA. Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: Solar activity was very low.

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

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

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet for the next two days (22-23 August) and quiet to unsettled on day three (24 August).

III. Event Probabilities 22 Aug-24 Aug

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

IV. Penticton 10.7 cm Flux

• Observed 21 Aug 067
• Predicted 22 Aug-24 Aug 066/066/066
• 90 Day Mean 21 Aug 066

V. Geomagnetic A Indices

• Observed Afr/Ap 20 Aug 005/006
• Estimated Afr/Ap 21 Aug 005/005
• Predicted Afr/Ap 22 Aug-24 Aug 005/005-005/005-007/008

VI. Geomagnetic Activity Probabilities 22 Aug-24 Aug

A. Middle Latitudes

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

B. High Latitudes

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