Viewing archive of Thursday, 31 March 2011
Solar activity report
Any mentioned solar flare in this report has a scaling factor applied by the Space Weather Prediction Center (SWPC). Because of the SWPC scaling factor, solar flares are reported as 42% smaller than for the science quality data. The scaling factor has been removed from our archived solar flare data to reflect the true physical units.
Report of Solar-Geophysical Activity 2011 Mar 31 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 090 Issued at 2200Z on 31 Mar 2011IA. Analysis of Solar Active Regions and Activity from 30-2100Z to 31-2100Z Solar activity remained at low levels. Region 1176
(S16W51) produced a C2/Sf flare at 31/1535Z. Region 1183 (N15E14)
produced a C1 flare at 31/0202Z. Both regions exhibited gradual
decay during the period. No new regions were assigned.
IB. Solar Activity Forecast
Solar activity is expected to be low
during the period (01 - 03 April) with a chance for moderate levels
(isolated M-class).
IIA. Geophysical Activity Summary 30-2100Z to 31-2100Z
Geomagnetic activity was at quiet levels.
IIB. Geophysical Activity Forecast
Geomagnetic activity is
expected to be at quiet to unsettled levels on day 1 (01 April) due
to possible coronal hole high-speed stream effects. Activity is
expected to decrease to quiet levels during days 2 - 3 (02 - 03
April).
III. Event Probabilities 01 Apr to 03 Apr
| Class M | 30% | 30% | 30% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 31 Mar 113 Predicted 01 Apr-03 Apr 115/115/110 90 Day Mean 31 Mar 098
V. Geomagnetic A Indices
Observed Afr/Ap 30 Mar 004/005 Estimated Afr/Ap 31 Mar 003/005 Predicted Afr/Ap 01 Apr-03 Apr 008/008-005/005-005/005
VI. Geomagnetic Activity Probabilities 01 Apr to 03 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 10% | 10% |
| Minor storm | 05% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 15% | 15% |
| Minor storm | 10% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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