Viewing archive of Tuesday, 31 May 2011
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 2011 May 31 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 151 Issued at 2200Z on 31 May 2011IA. Analysis of Solar Active Regions and Activity from 30-2100Z to 31-2100Z
Solar activity has been low. Region 1226 (S22E27) and
Region 1227 (S18E39) each produced C1 x-ray events in the past 24
hours. Region 1226 was classified as a Dhc group with Beta magnetic
characteristics while Region 1227 was a Dsi group with more complex
Beta-Gamma characteristics. Region 1228 (N17E50) rapidly evolved
into a Cso type group as new trailing spots emerged. New Region
1230 (N19E58) was numbered today. This new region, and the remainng
regions, were generally quiescent, small and magnetically simple.
IB. Solar Activity Forecast
Solar activity is expected to be low,
with a slight chance for M-class events for the next three days (1 -
3 Jun).
IIA. Geophysical Activity Summary 30-2100Z to 31-2100Z
The geomagnetic field ranged from quiet to active levels over the
past 24 hours. Heliospheric imagery from STEREO-B suggests the
increased activity was the result of a transient, weak CME. The
greater than 2 MeV electron flux at geosynchronous orbit reached
high levels during the period.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be unsettled to active on day 1 (01 Jun) , quiet to
unsettled on day 2 (02 Jun), and unsettled to active on day 3 (03
Jun). ENLIL model output indicates the passage of the 29 May CME
early on day 1. A brief return to generally quiet conditions on day
2 is followed by disturbed conditions on day 3 as a recurrent
coronal hole high speed stream begins to influence the
magnetosphere.
III. Event Probabilities 01 Jun to 03 Jun
| Class M | 20% | 20% | 20% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 31 May 112 Predicted 01 Jun-03 Jun 115/115/110 90 Day Mean 31 May 108
V. Geomagnetic A Indices
Observed Afr/Ap 30 May 007/009 Estimated Afr/Ap 31 May 010/012 Predicted Afr/Ap 01 Jun-03 Jun 010/010-007/008-010/010
VI. Geomagnetic Activity Probabilities 01 Jun to 03 Jun
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 10% | 20% |
| Minor storm | 10% | 05% | 10% |
| Major-severe storm | 05% | 01% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 15% | 20% |
| Minor storm | 25% | 10% | 20% |
| Major-severe storm | 10% | 05% | 15% |
All times in UTC
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