Viewing archive of Tuesday, 4 October 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 Oct 04 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 277 Issued at 2200Z on 04 Oct 2011IA. Analysis of Solar Active Regions and Activity from 03-2100Z to 04-2100Z Solar activity has been at low levels for the past 24
hours. Region 1302 (N13W85) produced the largest event of the
period, a long duration C7/Sf x-ray flare at 04/0923Z. Two new
regions were numbered today, Region 1311 (S12E20) in the southeast
quadrant, and Region 1312 (N22E74) in the northeast quadrant.
Finally, a full halo CME was observed in LASCO C2 imagery 04/1248Z.
After careful analysis, this event was determined to be a farsided,
non-Earth directed event.
IB. Solar Activity Forecast
Solar activity is expected to be at
low levels with a slight chance for M-class flares for the next
three days (05-07 October). These slightly elevated flare
probabilities are due to there being over 8 active sunspot regions
on the disk. Even though Region 1302 will be rotating off the
visible disk in one day, Region 1311 and 1310 (S32E02) have shown
some rapid development.
IIA. Geophysical Activity Summary 03-2100Z to 04-2100Z
The geomagnetic field has been at predominantly quiet levels for the
past 24 hours. 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 active with isolated minor storm levels possible on
days one and two (05-06 October), as three Earthbound CMEs are
forecasted to arrive. A return to quiet to unsettled levels on day
three (07 October) is expected, as the effects of the CMEs wane.
III. Event Probabilities 05 Oct to 07 Oct
| Class M | 20% | 20% | 20% |
| Class X | 05% | 01% | 01% |
| Proton | 05% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 04 Oct 130 Predicted 05 Oct-07 Oct 125/120/120 90 Day Mean 04 Oct 112
V. Geomagnetic A Indices
Observed Afr/Ap 03 Oct 003/006 Estimated Afr/Ap 04 Oct 005/007 Predicted Afr/Ap 05 Oct-07 Oct 015/015-018/018-008/008
VI. Geomagnetic Activity Probabilities 05 Oct to 07 Oct
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 45% | 45% | 15% |
| Minor storm | 20% | 25% | 05% |
| Major-severe storm | 05% | 05% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 45% | 45% | 20% |
| Minor storm | 30% | 35% | 10% |
| Major-severe storm | 05% | 05% | 01% |
All times in UTC
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