Joint USAF/NOAA Report of Solar and Geophysical Activity 01 May 2005
Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2005 May 01 2200 UTC
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 121 Issued at 2200Z on 01 May 2005
IA. Analysis of Solar Active Regions and Activity from 30/2100Z
to 01/2100Z: Solar activity was low. A C1.9 flare occurred at
01/1638 UTC from a region on the east limb at approximately S12.
Region 756 (S06W11) has decayed slightly in area. No new regions
were numbered.
IB. Solar Activity Forecast: Solar activity is expected to be at
low levels with a chance for an isolated M-class flare from Region
756.
IIA. Geophysical Activity Summary 30/2100Z to 01/2100Z:
The geomagnetic field was at unsettled to minor storm levels with an
isolated major storm period between 01/0300 and 01/0600 UTC. Solar
wind at ACE remained between approximately 600 km/s and 700 km/s.
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 unsettled to active with an isolated minor storm
period possible on 02 May. On 03 – 04 May, conditions are expected
to decrease to quiet to unsettled as the coronal hole high speed
stream moves out of geoeffective position.
III.
- Event Probabilities 02 May-04 May
- Class M 30/30/30
- Class X 01/01/01
- Proton 01/01/01
- PCAF green
IV. Penticton 10.7 cm Flux
- Observed 01 May 112
- Predicted 02 May-04 May 110/110/110
- 90 Day Mean 01 May 091
V. Geomagnetic A Indices
- Observed Afr/Ap 30 Apr 013/021
- Estimated Afr/Ap 01 May 020/026
- Predicted Afr/Ap 02 May-04 May 018/020-008/015-005/008
VI. Geomagnetic Activity Probabilities 02 May-04 May
A. Middle Latitudes
- Active 30/20/15
- Minor storm 15/10/05
- Major-severe storm 05/01/01
B. High Latitudes
- Active 35/25/20
- Minor storm 15/10/10
- Major-severe storm 10/05/01
