Joint USAF/NOAA Report of Solar and Geophysical Activity 31 May 2005
Prepared jointly by the U.S. Dept. of Commerce, NOAA,
Space Environment Center and the U.S. Air Force.
Updated 2005 May 31 2210 UTC
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 151 Issued at 2200Z on 31 May 2005
IA. Analysis of Solar Active Regions and Activity from 30/2100Z
to 31/2100Z: Solar activity was low. Region 770 (N12W27), a
seemingly simple spot group, had the one C-class flare of the day.
It produced a C2/Sf at 1442UTC with associated type II sweep. It has
been quiet since that event. One new region, Region 772 (S18E50) was
numbered, making a total of five spotted regions visible.
IB. Solar Activity Forecast: Solar activity is expected to persist
at the low level.
IIA. Geophysical Activity Summary 30/2100Z to 31/2100Z:
The geomagnetic field was unsettled to active. Yesterday’s storm
conditions have passed and the field has returned to more normal
conditions. Energetic electrons at geosynchronous orbit attained
high levels during the past 24 hours.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be generally unsettled. There is a slight chance of a
small disturbance later in the period from a possible CME associated
with the C2/Sf with type II that occurred today.
III. Event Probabilities 01 Jun-03 Jun
- Class M 10/10/10
- Class X 01/01/01
- Proton 01/01/01
- PCAF green
IV. Penticton 10.7 cm Flux
- Observed 31 May 096
- Predicted 01 Jun-03 Jun 095/095/095
- 90 Day Mean 31 May 092
V. Geomagnetic A Indices
- Observed Afr/Ap 30 May 032/067
- Estimated Afr/Ap 31 May 015/018
- Predicted Afr/Ap 01 Jun-03 Jun 010/015-010/012-010/018
VI. Geomagnetic Activity Probabilities 01 Jun-03 Jun
A. Middle Latitudes
- Active 25/25/25
- Minor storm 10/10/10
- Major-severe storm 05/05/05
B. High Latitudes
- Active 30/30/30
- Minor storm 10/10/10
- Major-severe storm 05/05/05
