Viewing archive of Friday, 12 August 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 Aug 12 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 224 Issued at 2200Z on 12 Aug 2011IA. Analysis of Solar Active Regions and Activity from 11-2100Z to 12-2100Z
Solar activity was very low. Todays largest event was
a B6 at 11/2309Z which appeared to originate from Region 1263 (N17,
L=296, about a day beyond west limb at the time of the event). The
solar disk now consists of only two spotted regions, Region 1269
(S22E03) and Region 1270 (N23E41). Both groups are very small and
only possess spots without penumbra. A filament eruption in the
northeast quadrant and associated CME were observed, beginning at
about 0336Z. The CME appears to be travelling well out of the
ecliptic plane and is not likely to be geoeffective.
IB. Solar Activity Forecast
Solar activity is expected to be very
low for the next three days.
IIA. Geophysical Activity Summary 11-2100Z to 12-2100Z
The geomagnetic field was quiet during the past 24 hours. Solar wind
observations of the Phi angle from the ACE spacecraft appeared to
indicate a transition to a negative polarity sector. The greater
than 2 MeV electron flux at geosynchronous orbit was at high levels
throughout the period.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be predominantly quiet for day 1 (13 August). An
increase to unsettled levels with a chance for active periods is
expected for days 2 and 3 (14-15 August) as a co-rotating
interaction region followed by a negative polarity coronal hole high
speed stream are expected to become weakly geoeffective.
III. Event Probabilities 13 Aug to 15 Aug
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 12 Aug 083 Predicted 13 Aug-15 Aug 082/082/080 90 Day Mean 12 Aug 096
V. Geomagnetic A Indices
Observed Afr/Ap 11 Aug 003/006 Estimated Afr/Ap 12 Aug 007/007 Predicted Afr/Ap 13 Aug-15 Aug 007/007-012/012-010/010
VI. Geomagnetic Activity Probabilities 13 Aug to 15 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 40% | 30% |
| Minor storm | 05% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 40% | 35% |
| Minor storm | 10% | 15% | 15% |
| Major-severe storm | 01% | 05% | 05% |
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
Whitehorse, YT, Yellowknife, NTFairbanks, AK
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