Viewing archive of Wednesday, 28 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 28 2203 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 149 Issued at 2200Z on 28 May 2008IA. Analysis of Solar Active Regions and Activity from 27-2100Z to 28-2100Z Solar activity was at very low levels. The visible
disk remained spotless.
IB. Solar Activity Forecast
Solar activity is expected to remain
at very low levels.
IIA. Geophysical Activity Summary 27-2100Z to 28-2100Z
The geomagnetic field was at mostly unsettled levels today. At about
27/2200Z, the ACE satellite detected a Solar Sector Boundary
crossing from a negative (toward) orientation to a positive (away)
orientation. At about 28/0130Z, a shock was detected at ACE with
subsequent sharp increases in both density and wind speed,
indicative of a co-rotating interaction region (CIR). The CIR was
followed by the onset of a high speed stream at about 28/0500Z;
solar wind velocities increased to about 525 km/s by the end of the
summary period. The greater than 2 MeV electron flux at
geosynchronous orbit reached high levels for a brief period today.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at quiet to unsettled levels, with a chance for
isolated active periods, during all three days of the forecast
period (29 May to 31 May) due to the high speed stream.
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 071
V. Geomagnetic A Indices
Observed Afr/Ap 27 May 002/003 Estimated Afr/Ap 28 May 010/010 Predicted Afr/Ap 29 May-31 May 008/010-008/010-008/008
VI. Geomagnetic Activity Probabilities 29 May to 31 May
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 30% | 30% | 25% |
| Minor storm | 10% | 10% | 05% |
| Major-severe storm | 05% | 05% | 05% |
All times in UTC
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