Viewing archive of Thursday, 15 September 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 Sep 15 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 258 Issued at 2200Z on 15 Sep 2011IA. Analysis of Solar Active Regions and Activity from 14-2100Z to 15-2100Z Solar activity was low. Nine C-class flares were
observed during the period. The largest was a C4/Sf at 15/0029Z from
Region 1297 (S18W64). Region 1295 (N22E30) showed growth in its
trailing spots.
IB. Solar Activity Forecast
Solar activity is expected to be low
with a chance for isolated M-class flares during the period (16-18
September).
IIA. Geophysical Activity Summary 14-2100Z to 15-2100Z
The geomagnetic field was at predominantly quiet levels. The greater
than 2 MeV electron flux at geosynchronous orbit was at high levels
throughout the period.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at predominantly quiet levels on day one (16
September). Unsettled to active levels are possible late on day one,
due to the expected arrival of the full halo CME observed at
14/0000Z. Activity is expected to be at unsettled to active levels,
with isolated minor storm levels at high latitudes on day two (17
September) as the CME continues. Activity is expected to decrease to
quiet to active levels on day three (18 September).
III. Event Probabilities 16 Sep to 18 Sep
| Class M | 35% | 35% | 35% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 15 Sep 141 Predicted 16 Sep-18 Sep 140/140/135 90 Day Mean 15 Sep 101
V. Geomagnetic A Indices
Observed Afr/Ap 14 Sep 005/004 Estimated Afr/Ap 15 Sep 004/004 Predicted Afr/Ap 16 Sep-18 Sep 010/010-018/020-010/015
VI. Geomagnetic Activity Probabilities 16 Sep to 18 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 25% | 25% | 25% |
| Minor storm | 10% | 15% | 10% |
| Major-severe storm | 01% | 05% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 30% | 30% | 30% |
| Minor storm | 15% | 20% | 15% |
| Major-severe storm | 05% | 05% | 01% |
All times in UTC
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