Joint USAF/NOAA Report of Solar and Geophysical Activity 08 Apr 2007

Product: Report of Solar-Geophysical Activity
Issued: 2007 Apr 08 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 098 Issued at 2200Z on 08 Apr 2007

IA. Analysis of Solar Active Regions and Activity from 07/2100Z to 08/2100Z: Solar activity was at very low levels. The visible disk remains void of sunspots. No new regions were numbered today.

IB. Solar Activity Forecast: Solar activity is expected to remain at very low levels.

IIA. Geophysical Activity Summary 07/2100Z to 08/2100Z: The geomagnetic field was at quiet levels. The greater than 2 MeV electron flux at geosynchronous orbit reached high levels again today.

IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be at unsettled to active levels on 09 April due to the onset of a recurrent coronal hole. Isolated minor to major storm periods are possible once the coronal hole becomes geoeffective. Unsettled to isolated active conditions are expected on 10 April. Predominantly quiet to unsettled conditions are expected on 11 April as the coronal hole wanes.

III. Event Probabilities 09 Apr-11 Apr

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

IV. Penticton 10.7 cm Flux

• Observed 08 Apr 071
• Predicted 09 Apr-11 Apr 070/070/070
• 90 Day Mean 08 Apr 076

V. Geomagnetic A Indices

• Observed Afr/Ap 07 Apr 002/003
• Estimated Afr/Ap 08 Apr 003/008
• Predicted Afr/Ap 09 Apr-11 Apr 015/015-010/010-005/008

VI. Geomagnetic Activity Probabilities 09 Apr-11 Apr

A. Middle Latitudes

• Active 30/20/15
• Minor storm 15/10/05
• Major-severe storm 10/05/01

B. High Latitudes

• Active 35/25/20
• Minor storm 20/15/10
• Major-severe storm 15/05/05