Joint USAF/NOAA Report of Solar and Geophysical Activity 12 Apr 2006

Product: Report of Solar-Geophysical Activity
Issued: 2006 Apr 12 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 102 Issued at 2200Z on 12 Apr 2006

IA. Analysis of Solar Active Regions and Activity from 11/2100Z to 12/2100Z: Solar activity was very low. Region 873 (S04E35) has developed in complexity and is now a Dai class spot group. All other regions have remained quiescent.

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

IIA. Geophysical Activity Summary 11/2100Z to 12/2100Z: The geomagnetic field was 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 to unsettled on 13 April. Unsettled to active conditions with possible periods of minor storming are expected on 14 April, increasing to mostly active with possible minor to major storming on 15 April due to a recurrent coronal hole high speed stream. III. Event Probabilities 13 Apr-15 Apr

• Class M 05/05/05
• Class X 01/01/01
• Proton 01/01/01
• PCAF green

IV. Penticton 10.7 cm Flux

• Observed 12 Apr 081
• Predicted 13 Apr-15 Apr 080/080/080
• 90 Day Mean 12 Apr 080

V. Geomagnetic A Indices

• Observed Afr/Ap 11 Apr 003/005
• Estimated Afr/Ap 12 Apr 002/005
• Predicted Afr/Ap 13 Apr-15 Apr 005/010-015/025-020/040

VI. Geomagnetic Activity Probabilities 13 Apr-15 Apr A. Middle Latitudes

• Active 15/35/40
• Minor storm 01/15/20
• Major-severe storm 01/05/05

B. High Latitudes

• Active 20/35/20
• Minor storm 05/30/40
• Major-severe storm 01/15/20