Joint USAF/NOAA Report of Solar and Geophysical Activity 21 Apr 2007
Product: Report of Solar-Geophysical Activity
Issued: 2007 Apr 21 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 111 Issued at 2200Z on 21 Apr 2007
IA. Analysis of Solar Active Regions and Activity from 20/2100Z to 21/2100Z: 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 20/2100Z to 21/2100Z: The geomagnetic field was quiet.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to be quiet to unsettled with possible active periods at high latitudes on 22 April due to a recurrent coronal hole high speed stream. Expect quiet to unsettled conditions on 23 – 24 April.
III. Event Probabilities 22 Apr-24 Apr
- Class M 01/01/01
- Class X 01/01/01
- Proton 01/01/01
- PCAF Green
IV. Penticton 10.7 cm Flux
- Observed 21 Apr 069
- Predicted 22 Apr-24 Apr 070/070/070
- 90 Day Mean 21 Apr 075
V. Geomagnetic A Indices
- Observed Afr/Ap 20 Apr 002/003
- Estimated Afr/Ap 21 Apr 005/010
- Predicted Afr/Ap 22 Apr-24 Apr 010/015-008/008-005/005
VI. Geomagnetic Activity Probabilities 22 Apr-24 Apr
A. Middle Latitudes
- Active 25/20/15
- Minor storm 10/10/05
- Major-severe storm 01/01/01
B. High Latitudes
- Active 35/25/25
- Minor storm 20/15/15
- Major-severe storm 05/01/01