Viewing archive of Saturday, 10 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 10 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 344 Issued at 2200Z on 10 Dec 2011IA. Analysis of Solar Active Regions and Activity from 09-2100Z to 10-2100Z
Solar activity was low. Region 1375 (N09E39) produced a
C1 x-ray event at 10/0631Z. The remainder of the disk and limb was
quiet and stable.
IB. Solar Activity Forecast
Solar activity is expected to remain
at low levels with a slight chance for M-class activity all three
days of the period (11 - 13 December).
IIA. Geophysical Activity Summary 09-2100Z to 10-2100Z
The geomagnetic field was at quiet to unsettled levels. Solar wind
velocities gradually increased through the period from 350 km/s to a
peak of near 500 km/s at about 10/1000Z. Excursions of southward
interplanetary magnetic field Bz to -10 nT were observed between
01/0200Z - 0600Z.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be at quiet to unsettled levels with isolated active
periods on day one (11 December) due to effects of a recurrent
coronal hole high speed stream (CH HSS). A return to mostly quiet
conditions are expected by days two and three (12 - 13 December) as
effects from the CH HSS wane.
III. Event Probabilities 11 Dec to 13 Dec
| Class M | 20% | 20% | 20% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 10 Dec 140 Predicted 11 Dec-13 Dec 140/140/140 90 Day Mean 10 Dec 146
V. Geomagnetic A Indices
Observed Afr/Ap 09 Dec 003/003 Estimated Afr/Ap 10 Dec 005/005 Predicted Afr/Ap 11 Dec-13 Dec 007/008-005/005-005/005
VI. Geomagnetic Activity Probabilities 11 Dec to 13 Dec
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 05% | 05% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 10% | 10% |
| Minor storm | 05% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
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