Joint USAF/NOAA Report of Solar and Geophysical Activity 30 Apr 2008

Product: Report of Solar-Geophysical Activity
Issued: 2008 Apr 30 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 121 Issued at 2200Z on 30 Apr 2008

IA. Analysis of Solar Active Regions and Activity from 29/2100Z to 30/2100Z: Solar activity was very low. 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 29/2100Z to 30/2100Z: The geomagnetic field was quiet to unsettled. 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 with isolated active periods for the next three days (01-03 May). Elevated activity expected on day one is in response to the CME observed on 26 April. Activity on days two and three is in response to a recurrent coronal hole high speed stream that is expected to rotate into a geoeffective position.

III. Event Probabilities 01 May-03 May

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

IV. Penticton 10.7 cm Flux

• Observed 30 Apr 067
• Predicted 01 May-03 May 070/070/070
• 90 Day Mean 30 Apr 071

V. Geomagnetic A Indices

• Observed Afr/Ap 29 Apr 004/008
• Estimated Afr/Ap 30 Apr 010/010
• Predicted Afr/Ap 01 May-03 May 010/015-010/010-010/010

VI. Geomagnetic Activity Probabilities 01 May-03 May

A. Middle Latitudes

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

B. High Latitudes

• Active 50/40/40
• Minor storm 15/10/10
• Major-severe storm 05/05/05