Viewing archive of Thursday, 18 August 2005
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 2005 Aug 18 2204 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 2005IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z
Solar activity was very low. Newly numbered Region 799
(S12W56) was responsible for several B-class flares. LASCO imagery
showed a CME at 18/1654 UTC directed towards the southwest which was
likely associated with a B2 flare which occurred from Region 799 at
18/1605 UTC.
IB. Solar Activity Forecast
Solar activity is expected to be very
low to low.
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
The geomagnetic field was quiet to active due to the continued
influence of a coronal hole high speed stream. Solar wind speed at
ACE has gradually decreased from approximately 700 km/s to 620 km/s.
The greater than 2 MeV electron flux at geosynchronous orbit reached
high levels today.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet to unsettled with a chance of isolated active
periods on 19 August as the coronal hole high speed stream moves out
of geoeffective position. Quiet to unsettled conditions are expected
on 20 - 21 August.
III. Event Probabilities 19 Aug to 21 Aug
| Class M | 05% | 05% | 05% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 18 Aug 083 Predicted 19 Aug-21 Aug 085/085/085 90 Day Mean 18 Aug 093
V. Geomagnetic A Indices
Observed Afr/Ap 17 Aug 011/018 Estimated Afr/Ap 18 Aug 010/015 Predicted Afr/Ap 19 Aug-21 Aug 008/010-004/007-004/007
VI. Geomagnetic Activity Probabilities 19 Aug to 21 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 15% | 15% |
| Minor storm | 10% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 25% | 20% | 20% |
| Minor storm | 10% | 10% | 10% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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