Joint USAF/NOAA Report of Solar and Geophysical Activity 23 May 2007
Product: Report of Solar-Geophysical Activity
Issued: 2007 May 23 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 143 Issued at 2200Z on 23 May 2007
IA. Analysis of Solar Active Regions and Activity from 22/2100Z to 23/2100Z: Solar activity continues at very low levels. Region 956 (N03W60) produced a B5 flare at 23/0732Z. A Type II radio sweep (582 km/s) accompanied this flare and a CME was obvious on STEREO imagery. Region 956 continues its slow decay and is now a small beta sunspot group.
IB. Solar Activity Forecast: Solar activity is expected to continue at very low levels. Region
IIA. Geophysical Activity Summary 22/2100Z to 23/2100Z: The geomagnetic field ranged from quiet to major storming. Extended periods of southward Bz accounted for the most disturbed periods. Transient flow from the 19 May CME likely contributed to this disturbance.
IIB. Geophysical Activity Forecast: The geomagnetic field is expected to range from unsettled to major storming over the next three days. A recurrent coronal hole high speed stream is rotating into a geoeffective position and is expected to produce storm periods. Transient material from today’s CME and the CME on 22 May will likely contribute to the disturbed periods.
III. Event Probabilities 24 May-26 May
- Class M 01/01/01
- Class X 01/01/01
- Proton 01/01/01
- PCAF green
IV. Penticton 10.7 cm Flux
- Observed 23 May 070
- Predicted 24 May-26 May 070/070/070
- 90 Day Mean 23 May 074
V. Geomagnetic A Indices
- Observed Afr/Ap 22 May 010/011
- Estimated Afr/Ap 23 May 025/030
- Predicted Afr/Ap 24 May-26 May 012/020-020/025-025/025
VI. Geomagnetic Activity Probabilities 24 May-26 May
A. Middle Latitudes
- Active 30/40/40
- Minor storm 15/25/25
- Major-severe storm 05/10/10
B. High Latitudes
- Active 40/45/45
- Minor storm 25/35/35
- Major-severe storm 15/20/20
