Joint USAF/NOAA Report of Solar and Geophysical Activity 11 Aug 2003
Joint USAF/NOAA Report of Solar and Geophysical Activity 11 Aug 2003
SDF Number 223 Issued at 2200Z on 11 Aug 2003
IA. Analysis of Solar Active Regions and Activity from 10/2100Z
to 11/2100Z: Solar activity decreased to very low levels. Several
impulsive B-class flares comprised today’s flare activity. Region
424 (S18W54) has shown a slight decrease in penumbral coverage today
although it continues to exhibit beta-gamma characteristics. Region
431 (S13E43) also underwent slight decay and it too appears to
possess a beta-gamma magnetic structure. No new regions were
numbered today.
IB. Solar Activity Forecast: Solar activity is expected to be at
low levels. An isolated M-class flare is possible from Region 424.
IIA. Geophysical Activity Summary 10/2100Z to 11/2100Z:
The geomagnetic field was at quiet to unsettled levels. 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 minor storm levels for the first two
days of the period due to a recurrent high speed coronal hole
stream. Day three should decrease to predominantly unsettled
conditions as the coronal hole wanes.
III. Event Probabilities 12 Aug-14 Aug
- Class M 20/20/20
- Class X 05/05/05
- Proton 01/01/01
- PCAF green
IV. Penticton 10.7 cm Flux
- Observed 11 Aug 129
- Predicted 12 Aug-14 Aug 130/125/120
- 90 Day Mean 11 Aug 126
V. Geomagnetic A Indices
- Observed Afr/Ap 10 Aug 009/012
- Estimated Afr/Ap 11 Aug 008/008
- Predicted Afr/Ap 12 Aug-14 Aug 020/020-020/035-012/020
VI. Geomagnetic Activity Probabilities 12 Aug-14 Aug
A. Middle Latitudes
- Active 35/35/25
- Minor storm 20/20/10
- Major-severe storm 10/10/01
B. High Latitudes
- Active 40/45/40
- Minor storm 20/35/15
- Major-severe storm 10/15/05