Joint USAF/NOAA Report of Solar and Geophysical Activity 04 May 2008

Product: Report of Solar-Geophysical Activity
Issued: 2008 May 04 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 125 Issued at 2200Z on 04 May 2008

IA. Analysis of Solar Active Regions and Activity from 03/2100Z to 04/2100Z: Solar activity was very low. New Region 993 (S29E27) emerged on the disk during the period as a small, simple Bxo Beta group. The region has a new cycle magnetic configuration and appears to be growing slowly.

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

IIA. Geophysical Activity Summary 03/2100Z to 04/2100Z: The geomagnetic field was at quiet to unsettled levels. Solar wind velocities, as measured at the ACE satellite, remain elevated at about 550 km/s.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at quiet to unsettled levels with a chance for isolated active periods all three days of the forecast period (05-07 May) due to the high-speed stream.

III. Event Probabilities 05 May-07 May

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

IV. Penticton 10.7 cm Flux

• Observed 04 May 068
• Predicted 05 May-07 May 068/068/068
• 90 Day Mean 04 May 071

V. Geomagnetic A Indices

• Observed Afr/Ap 03 May 009/012
• Estimated Afr/Ap 04 May 008/012
• Predicted Afr/Ap 05 May-07 May 008/008-008/010-008/008

VI. Geomagnetic Activity Probabilities 05 May-07 May

A. Middle Latitudes

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

B. High Latitudes

• Active 30/30/30
• Minor storm 10/10/10
• Major-severe storm 05/05/05