Viewing archive of Friday, 21 January 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 Jan 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 021 Issued at 2200Z on 21 Jan 2011IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z
Solar activity was low. Region 1147 (N24W07) and new
Region 1149 (N18W05) produced several C-class flares during the
period. Region 1149 produced a C3 flare at 21/0417Z. This was the
largest flare observed during the past 24 hours.
IB. Solar Activity Forecast
Solar activity is expected to be low
with a slight chance for an isolated M-class flare from Region 1149.
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field was quiet.
IIB. Geophysical Activity Forecast
The geomagnetic field is
expected to be quiet to unsettled on day one (22 January), due to a
coronal hole high-speed stream (CH HSS). Activity should decrease to
quiet levels on days two and three (23 - 24 January) as the effects
of the CH HSS wane.
III. Event Probabilities 22 Jan to 24 Jan
| Class M | 10% | 10% | 10% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Jan 088 Predicted 22 Jan-24 Jan 085/085/085 90 Day Mean 21 Jan 084
V. Geomagnetic A Indices
Observed Afr/Ap 20 Jan 004/003 Estimated Afr/Ap 21 Jan 005/005 Predicted Afr/Ap 22 Jan-24 Jan 007/007-005/005-005/005
VI. Geomagnetic Activity Probabilities 22 Jan to 24 Jan
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 05% |
| Minor storm | 01% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 20% | 15% | 10% |
| Minor storm | 05% | 01% | 01% |
| Major-severe storm | 01% | 01% | 01% |
All times in UTC
Current data suggests there is a slight possibility for aurora to appear at the following high latitude regions in the near future
TórshavnOulu, Rovaniemi, Sodankylä
Trondheim
Arkhangelsk
Kiruna, Luleå, Umeå
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