Viewing archive of Thursday, 29 December 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 Dec 29 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 363 Issued at 2200Z on 29 Dec 2011IA. Analysis of Solar Active Regions and Activity from 28-2100Z to 29-2100Z Solar activity has been at moderate levels for the past
24 hours. Region 1389 (S23E58) produced the largest event of the
period, an M1/1F flare at 29/1350Z. Region 1398 continues to grow
and evolve as it rotates around the east limb.
IB. Solar Activity Forecast
Solar activity is expected to be at
low to moderate levels for the next three days (30 December - 01
January).
IIA. Geophysical Activity Summary 28-2100Z to 29-2100Z
The geomagnetic field has been at quiet to unsettled levels for
the past 24 hours. Solar wind speeds, as measured by the ACE
spacecraft, have shown an increase from 280 km/s to almost 450 km/s
in the past 24 hours. Signatures in the solar wind indicate the
possible arrivals of the forecasted CMEs, however the intensity was
lower than expected.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at quiet to unsettled levels for day one (30
December) as the effects of the CMEs wane. Predominantly
quiet levels are expected on day two (31 December). A return to
quiet to unsettled levels is expected on day three (01 January) as a
coronal hole high speed stream moves into a geoeffective position.
III. Event Probabilities 30 Dec to 01 Jan
| Class M | 40% | 40% | 40% |
| Class X | 05% | 05% | 05% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 29 Dec 147 Predicted 30 Dec-01 Jan 145/145/145 90 Day Mean 29 Dec 144
V. Geomagnetic A Indices
Observed Afr/Ap 28 Dec 004/003 Estimated Afr/Ap 29 Dec 005/006 Predicted Afr/Ap 30 Dec-01 Jan 012/008-005/005-008/010
VI. Geomagnetic Activity Probabilities 30 Dec to 01 Jan
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 05% | 10% |
| Minor storm | 05% | 01% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 20% | 10% | 15% |
| Major-severe storm | 20% | 05% | 15% |
All times in UTC
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