Viewing archive of Tuesday, 18 August 2009
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 2009 Aug 18 2201 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 2009IA. Analysis of Solar Active Regions and Activity from 17-2100Z to 18-2100Z Solar activity was very low. No flares were detected.
The visible disk was spotless.
IB. Solar Activity Forecast
Solar activity is expected to be very
low.
IIA. Geophysical Activity Summary 17-2100Z to 18-2100Z
Geomagnetic field activity was at quiet levels.
IIB. Geophysical Activity Forecast
Geomagnetic field activity is
expected to increase to unsettled to active levels on day one (19
August) in response to a recurrent coronal hole high-speed stream
(CH HSS). Activity is expected to decrease to quiet to unsettled
levels on day two (20 August) as the CH HSS subsides. Quiet levels
are expected on day three (21 August).
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 067 Predicted 19 Aug-21 Aug 068/068/068 90 Day Mean 18 Aug 068
V. Geomagnetic A Indices
Observed Afr/Ap 17 Aug 002/003 Estimated Afr/Ap 18 Aug 005/005 Predicted Afr/Ap 19 Aug-21 Aug 015/012-007/007-005/005
VI. Geomagnetic Activity Probabilities 19 Aug to 21 Aug
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 30% | 25% | 10% |
| Minor storm | 10% | 05% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 40% | 30% | 15% |
| Minor storm | 20% | 10% | 01% |
| Major-severe storm | 05% | 01% | 01% |
All times in UTC
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