Viewing archive of Saturday, 13 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 13 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 225 Issued at 2200Z on 13 Aug 2011IA. Analysis of Solar Active Regions and Activity from 12-2100Z to 13-2100Z Solar activity has been very low. The largest X-ray
event of the past 24 hours was a B1 flare at 13/1431 UTC in Region
1269 (S21W09). All active regions currently on the solar disk are
small and simple.
IB. Solar Activity Forecast
Solar activity is expected to be very
low for the next three days (14-16 August). There is a slight chance
of an isolated C-class X-ray flare.
IIA. Geophysical Activity Summary 12-2100Z to 13-2100Z
The geomagnetic field was quiet. Solar wind observations from the
NASA ACE spacecraft indicate nominal background conditions with a
solar wind speed of about 320 km/s, density near 4 p/cc, and the
southward component of the IMF (Bz) fluctuating +/- 4 nT around
zero. 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 quiet to unsettled for the next three days (14-16
August) as a co-rotating interaction region followed by a negative
polarity coronal hole high-speed stream become geoeffective.
III. Event Probabilities 14 Aug to 16 Aug
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 13 Aug 083 Predicted 14 Aug-16 Aug 082/080/080 90 Day Mean 13 Aug 096
V. Geomagnetic A Indices
Observed Afr/Ap 12 Aug 003/005 Estimated Afr/Ap 13 Aug 004/005 Predicted Afr/Ap 14 Aug-16 Aug 012/012-010/010-010/010
VI. Geomagnetic Activity Probabilities 14 Aug to 16 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 40% | 30% | 30% |
| Minor storm | 10% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 40% | 35% | 30% |
| Minor storm | 15% | 15% | 10% |
| Major-severe storm | 05% | 05% | 05% |
All times in UTC
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