Viewing archive of Sunday, 2 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 02 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 275 Issued at 2200Z on 02 Oct 2011IA. Analysis of Solar Active Regions and Activity from 01-2100Z to 02-2100Z Solar activity was moderate. Regions 1302 (N16W55) and
1305 (N12W26) both produced M-class events during the past 24 hours.
The largest was an M3/1n from Region 1305 at 02/0050Z that was
associated with an Earth-directed CME visible in STEREO imagery with
an estimated speed of 532 km/s. Region 1302 decreased significantly
in area but maintained a beta-gamma-delta magnetic configuration.
Region 1305 developed some intermediate spots but held steady in
area and is still considered to have a beta-gamma magnetic class.
Region 1309 (N23E67) was numbered yesterday and is a Dso type group
with a beta magnetic configuration.
IB. Solar Activity Forecast
Solar activity is expected to be low
to moderate with a slight chance for X-class activity for the next
three days (03-05 October) due to flare potential from Regions 1302
and 1305.
IIA. Geophysical Activity Summary 01-2100Z to 02-2100Z
The geomagnetic field was quiet to unsettled with an isolated active
period during the 02/0900-1200Z synoptic period as measured by the
Boulder magnetometer. The increase in activity was due to effects
from a favorably positioned coronal hole high speed stream (CH HSS).
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 mostly quiet on days one and two (03-04 October) as
effects from the CH HSS subside. Day three (05 October) is expected
to begin with quiet to unsettled conditions. A chance for active
conditions and a slight chance for isolated minor storm periods is
expected later in the day due to effects from the combination of the
CMEs observed on 30 September and 01 October.
III. Event Probabilities 03 Oct to 05 Oct
| Class M | 75% | 75% | 75% |
| Class X | 20% | 20% | 15% |
| Proton | 15% | 15% | 10% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 02 Oct 131 Predicted 03 Oct-05 Oct 130/130/130 90 Day Mean 02 Oct 112
V. Geomagnetic A Indices
Observed Afr/Ap 01 Oct 012/009 Estimated Afr/Ap 02 Oct 010/010 Predicted Afr/Ap 03 Oct-05 Oct 005/005-005/005-015/015
VI. Geomagnetic Activity Probabilities 03 Oct to 05 Oct
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 05% | 40% |
| Minor storm | 05% | 01% | 20% |
| Major-severe storm | 01% | 01% | 05% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 05% | 45% |
| Minor storm | 05% | 01% | 20% |
| Major-severe storm | 01% | 01% | 05% |
All times in UTC
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