Viewing archive of Saturday, 17 May 2008
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 2008 May 17 2203 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 138 Issued at 2200Z on 17 May 2008IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z Solar activity was very low.
IB. Solar Activity Forecast
Solar activity is expected to remain
very low.
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic field was quiet.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet on the first day of the forecast period (18
May), becoming unsettled to active on day two as a recurrent coronal
hole high speed stream becomes geoeffective. Conditions on day
three will continue to be unsettled to active, with a chance for
minor storms at high latitudes.
III. Event Probabilities 18 May to 20 May
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 17 May 071 Predicted 18 May-20 May 072/072/072 90 Day Mean 17 May 071
V. Geomagnetic A Indices
Observed Afr/Ap 16 May 003/004 Estimated Afr/Ap 17 May 005/005 Predicted Afr/Ap 18 May-20 May 005/005-010/012-015/030
VI. Geomagnetic Activity Probabilities 18 May to 20 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 10% | 20% | 30% |
| Minor storm | 05% | 10% | 15% |
| Major-severe storm | 01% | 01% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 10% | 25% | 45% |
| Minor storm | 05% | 15% | 25% |
| Major-severe storm | 01% | 01% | 10% |
All times in UTC
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