Viewing archive of Thursday, 4 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 04 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 216 Issued at 2200Z on 04 Aug 2011IA. Analysis of Solar Active Regions and Activity from 03-2100Z to 04-2100Z
Solar activity was high. Region 1261 (N15W49) produced
a M9/2B at 0357Z. This event had associated Type II and Type IV
radio sweeps and a CME with an approximate speed of 2100 km/s in
STEREO A COR-2 imagery. Region 1261 has appeared to decay in the
southern most trailing spots and is classified as a Dai spot class
with a Beta-Gamma-Delta magnetic classification. Region 1263
(N17W18) has been relatively stable, only managing a few C-class
flares. Region 1263 is classified as a Dki spot class with a
Beta-Gamma-Delta magnetic classification. New Region 1266 (N18E38)
was numbered today.
IB. Solar Activity Forecast
Solar activity is expected to be
moderate to high. Further M-class activity is expected from Region
1261. Region 1263 has the potential for M-class activity as well.
There continues to be a chance for isolated major flare activity.
IIA. Geophysical Activity Summary 03-2100Z to 04-2100Z
The geomagnetic field was quiet. The greater than 10 MeV proton flux
at geosynchronous orbit crossed the 10 PFU threshold at 0635Z and
reached a peak of 80.1 PFU at 1030Z. The greater than 100 MeV
proton flux at geosynchronous orbit crossed the 1 PFU threshold at
0510Z and reached a peak of 1.8 PFU at 0740Z. This proton event was
associated with the M9 flare at 0357Z.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at minor to major storm levels with a chance for
severe storm periods as the effects of three CMEs are expected to
impact the Earths geomagnetic field early on 05 August. Active to
minor storm levels are expected on 06 August. Unsettled to active
levels are expected on 07 August.
III. Event Probabilities 05 Aug to 07 Aug
| Class M | 75% | 75% | 65% |
| Class X | 15% | 15% | 10% |
| Proton | 95% | 50% | 30% |
| PCAF | red | ||
IV. Penticton 10.7 cm Flux
Observed 04 Aug 116 Predicted 05 Aug-07 Aug 115/110/110 90 Day Mean 04 Aug 096
V. Geomagnetic A Indices
Observed Afr/Ap 03 Aug 003/003 Estimated Afr/Ap 04 Aug 005/005 Predicted Afr/Ap 05 Aug-07 Aug 050/050-030/030-015/020
VI. Geomagnetic Activity Probabilities 05 Aug to 07 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 30% | 25% |
| Minor storm | 35% | 30% | 15% |
| Major-severe storm | 50% | 20% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 30% | 25% |
| Minor storm | 30% | 30% | 20% |
| Major-severe storm | 55% | 30% | 15% |
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
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