Joint USAF/NOAA Report of Solar and Geophysical Activity 22 Apr 2007
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Product: Report of Solar-Geophysical Activity
Issued: 2007 Apr 22 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 112 Issued at 2200Z on 22 Apr 2007
IA. Analysis of Solar Active Regions and Activity from 21/2100Z to 22/2100Z: Solar activity was very low. The visible solar disk remains spotless.
IB. Solar Activity Forecast: Solar activity is expected to be very low.
IIA. Geophysical Activity Summary 21/2100Z to 22/2100Z: The geomagnetic field was quiet to unsettled. The solar wind speed increased to about 450 km/s due to a recurrent coronal hole high speed stream.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled for the next three days (23 – 25 April). Isolated active periods are possible at high latitudes on 23 April due to the coronal hole high speed stream.
III. Event Probabilities 23 Apr-25 Apr
- Class M 01/01/01
- Class X 01/01/01
- Proton 01/01/01
- PCAF Green
IV. Penticton 10.7 cm Flux
- Observed 22 Apr 069
- Predicted 23 Apr-25 Apr 070/070/070
- 90 Day Mean 22 Apr 074
V. Geomagnetic A Indices
- Observed Afr/Ap 21 Apr 002/002
- Estimated Afr/Ap 22 Apr 008/012
- Predicted Afr/Ap 23 Apr-25 Apr 010/010-005/005-005/005
VI. Geomagnetic Activity Probabilities 23 Apr-25 Apr
A. Middle Latitudes
- Active 25/20/20
- Minor storm 10/05/05
- Major-severe storm 01/01/01
B. High Latitudes
- Active 30/20/20
- Minor storm 15/05/05
- Major-severe storm 05/01/01