Joint USAF/NOAA Report of Solar and Geophysical Activity 31 Mar 2003
SDF Number 090 Issued at 2200Z on 31 Mar 2003
IA. Analysis of Solar Active Regions and Activity from 30/2100Z
to 31/2100Z: Solar activity was low. Occasional low C-class flares
were observed from Regions 318 (S13W49) and 321 (N06W16). Region 323
(S08W29) maintained its moderate size and magnetic complexity, but
was mostly stable this period. Region 319 (N13W57) underwent
considerable decay over the past 24 – 36 hours. New Regions 327
(S07W12) and 328 (S03E14) were numbered today. No other significant
developments were observed.
IB. Solar Activity Forecast: Solar activity is expected to be low.
There is a small chance for a low M-class flare from Region 323.
IIA. Geophysical Activity Summary 30/2100Z to 31/2100Z:
The geomagnetic field ranged from quiet to minor storm levels, with
occasional major storm periods at high latitudes. The high speed
stream that began early on 30 March continues. An extended period of
southward Bz that began at around 1100Z, has continued through the
end of the period and was responsible for the most disturbed
periods. The greater than 2 MeV electrons at geosynchronous orbit
reached high levels.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at unsettled to minor storm levels. Disturbed periods
due to high speed stream effects will continue for the next 2-3
days.
III. Event Probabilities 01 Apr-03 Apr
- Class M 30/30/30
- Class X 05/05/05
- Proton 01/01/01
- PCAF green
IV. Penticton 10.7 cm Flux
- Observed 31 Mar 160
- Predicted 01 Apr-03 Apr 160/155/150
- 90 Day Mean 31 Mar 134
V. Geomagnetic A Indices
- Observed Afr/Ap 30 Mar 019/026
- Estimated Afr/Ap 31 Mar 020/030
- Predicted Afr/Ap 01 Apr-03 Apr 015/020-015/020-015/015
VI. Geomagnetic Activity Probabilities 01 Apr-03 Apr
A. Middle Latitudes
- Active 40/40/30
- Minor storm 20/20/10
- Major-severe storm 10/10/05
B. High Latitudes
- Active 50/50/40
- Minor storm 30/30/20
- Major-severe storm 15/15/10
