Viewing archive of Monday, 21 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 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 080 Issued at 2200Z on 21 Mar 2011IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z
Solar activity increased to low levels. Isolated
C-class flares were observed, the largest of which was a
long-duration C4 at 21/1719Z from newly-numbered Region 1176
(S13E81). Region 1176 was the return of old Region 1165, which
produced M-class flares during its previous rotation. SOHO/LASCO
images showed a halo-CME, first visible in C2 images at 21/0236Z.
The halo-CME was determined to be a backside event associated with a
flare from old Region 1169 (N20, L=061).
IB. Solar Activity Forecast
Solar activity is expected to be low
during days 1 - 3 (22 - 24 March) with a chance for an M-class flare
from Region 1176.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
Geomagnetic field activity was at quiet levels. A greater than 10 MeV
proton event at geosynchronous orbit began at 21/1950Z and was in
progress at the time of this report. Stereo-A EUVI 195 images
indicated the source for the proton event was likely a flare from
old Region 1169 which also spawned the back sided halo-CME mentioned
above.
IIB. Geophysical Activity Forecast
Geomagnetic activity is
expected to be at quiet levels during days 1 - 2 (22 - 23 March).
Geomagnetic activity is expected to increase to quiet to unsettled
levels on day 3 (24 March) as a coronal hole high-speed stream
begins to disturb the field. The greater than 10 MeV event at
geosynchronous orbit is expected to end on day 1 (March 22).
III. Event Probabilities 22 Mar to 24 Mar
| Class M | 30% | 30% | 30% |
| Class X | 05% | 05% | 05% |
| Proton | 10% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Mar 101 Predicted 22 Mar-24 Mar 115/125/135 90 Day Mean 21 Mar 094
V. Geomagnetic A Indices
Observed Afr/Ap 20 Mar 004/004 Estimated Afr/Ap 21 Mar 002/004 Predicted Afr/Ap 22 Mar-24 Mar 005/005-005/005-008/008
VI. Geomagnetic Activity Probabilities 22 Mar to 24 Mar
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 10% | 15% |
| Minor storm | 01% | 01% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 20% |
| Minor storm | 01% | 01% | 10% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
Current data suggests there is a slight possibility for aurora to appear at the following high latitude regions in the near future
Gillam, MB, Whitehorse, YT, Yellowknife, NTFairbanks, AK, Utqiagvik, AK
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