Viewing archive of Thursday, 28 May 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 May 28 2201 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 148 Issued at 2200Z on 28 May 2009IA. Analysis of Solar Active Regions and Activity from 27-2100Z to 28-2100Z Solar activity continued to be very low. The disk is
spotless and no flares occurred.
IB. Solar Activity Forecast
Solar activity is expected to remain
very low.
IIA. Geophysical Activity Summary 27-2100Z to 28-2100Z
The geomagnetic field was quiet to mildly unsettled. A sudden impulse
measuring 33 nT at Boulder occurred at 0520 UTC, bringing unsettled
conditions in its wake. The source of this impulse is of dubious
origin.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet throughout the forecast period.
III. Event Probabilities 29 May to 31 May
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | Green | ||
IV. Penticton 10.7 cm Flux
Observed 28 May 068 Predicted 29 May-31 May 068/068/068 90 Day Mean 28 May 069
V. Geomagnetic A Indices
Observed Afr/Ap 27 May 002/003 Estimated Afr/Ap 28 May 005/005 Predicted Afr/Ap 29 May-31 May 005/005-005/005-005/005
VI. Geomagnetic Activity Probabilities 29 May to 31 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 10% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 10% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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