Joint USAF/NOAA Report of Solar and Geophysical Activity 01 Apr 2005
Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2005 Apr 01 2210 UTC
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 091 Issued at 2200Z on 01 Apr 2005
IA. Analysis of Solar Active Regions and Activity from 31/2100Z
to 01/2100Z: Solar activity was at very low levels today. Region
747 (S09E10) underwent growth this period in sunspot area and
magnetic complexity. Region 748 (N09E46) is a single HSX alpha spot
group. No new regions were numbered today.
IB. Solar Activity Forecast: Solar activity is expected to be at
very low levels.
IIA. Geophysical Activity Summary 31/2100Z to 01/2100Z:
The geomagnetic field was at predominantly quiet to unsettled levels.
A brief period of active conditions were observed at the high
latitudes in conjunction with a sustained southward Bz occurring
between 01/0600 and 0900Z. 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 at unsettled to active levels throughout the period
due to a recurrent coronal hole high speed stream. Isolated minor
storm conditions may be possible on 3 and 4 April.
III. Event Probabilities 02 Apr-04 Apr
- Class M 01/01/01
- Class X 01/01/01
- Proton 01/01/01
- PCAF green
IV. Penticton 10.7 cm Flux
- Observed 01 Apr 078
- Predicted 02 Apr-04 Apr 080/080/085
- 90 Day Mean 01 Apr 096
V. Geomagnetic A Indices
- Observed Afr/Ap 31 Mar 005/009
- Estimated Afr/Ap 01 Apr 007/010
- Predicted Afr/Ap 02 Apr-04 Apr 015/015-015/025-020/035
VI. Geomagnetic Activity Probabilities 02 Apr-04 Apr
A. Middle Latitudes
- Active 30/30/35
- Minor storm 10/10/20
- Major-severe storm 05/05/15
B. High Latitudes
- Active 30/40/40
- Minor storm 10/20/35
- Major-severe storm 05/10/20
