Viewing archive of Saturday, 18 August 2007
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 2007 Aug 18 2203 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 230 Issued at 2200Z on 18 Aug 2007IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z Solar activity continues at very low levels. A new
region, rotating into view near S05 on the east limb, produced
occasional B-class flares. The remainder of the disk is spotless.
IB. Solar Activity Forecast
Solar activity is expected to be very
low to low. Early indications are that the region rotating into view
on the SE limb will have C-class flare potential.
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic field was quiet. Solar wind speed declined to near
380 km/s.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet to unsettled. Enhanced solar wind flow from a
coronal hole may produce occasional unsettled periods over the next
few days.
III. Event Probabilities 19 Aug to 21 Aug
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 18 Aug 068 Predicted 19 Aug-21 Aug 070/070/070 90 Day Mean 18 Aug 071
V. Geomagnetic A Indices
Observed Afr/Ap 17 Aug 002/005 Estimated Afr/Ap 18 Aug 002/005 Predicted Afr/Ap 19 Aug-21 Aug 008/012-005/005-005/005
VI. Geomagnetic Activity Probabilities 19 Aug to 21 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 15% | 15% |
| Minor storm | 05% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 20% | 20% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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