Viewing archive of Thursday, 17 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 17 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 076 Issued at 2200Z on 17 Mar 2011IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z Solar activity was at very low levels. Region 1169
(N18W89) produced a single B4 X-ray event at 17/1153Z. After further
analysis, the partial-halo CME associated with the long-duration
C3/Sf flare at 16/2034Z from Region 1169 (N17W75 at the time of the
event) did not appear to be Earth-directed. New Region 1174 (N22W36)
emerged on the disk as a simple bi-polar group.
IB. Solar Activity Forecast
Solar activity is expected to be at
predominately very low levels for the next three days (18 - 20
March). A chance for C-class activity exists all three days.
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic field was quiet at all latitudes.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet for the next three days (18 - 20 March).
III. Event Probabilities 18 Mar to 20 Mar
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 17 Mar 090 Predicted 18 Mar-20 Mar 085/080/085 90 Day Mean 17 Mar 094
V. Geomagnetic A Indices
Observed Afr/Ap 16 Mar 001/000 Estimated Afr/Ap 17 Mar 002/002 Predicted Afr/Ap 18 Mar-20 Mar 005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 18 Mar to 20 Mar
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 10% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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