Viewing archive of Thursday, 21 March 2013
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 2013 Mar 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 80 Issued at 2200Z on 21 Mar 2013IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z Solar activity has been at low levels for the past 24 hours.
The largest solar event of the period was a C3 event observed at
21/1822Z from Region 1692 (N09W85). There are currently 4 numbered
sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is likely to be low with a
slight chance for an M-class flare on day one (22 Mar) and expected to
be very low with a chance for a C-class flares on days two and three (23
Mar, 24 Mar).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic
field has been at quiet to active levels for the past 24 hours. Solar
wind speed, as measured by the ACE spacecraft, reached a peak speed of
574 km/s at 21/0122Z. Total IMF reached 9 nT at 20/2108Z. The maximum
southward component of Bz reached -8 nT at 20/2244Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 1851 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on days one and two (22 Mar, 23 Mar)
and quiet levels on day three (24 Mar).
III. Event Probabilities 22 Mar to 24 Mar
| Class M | 10% | 05% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Mar 106 Predicted 22 Mar-24 Mar 105/100/100 90 Day Mean 21 Mar 116
V. Geomagnetic A Indices
Observed Afr/Ap 20 Mar 007/009 Estimated Afr/Ap 21 Mar 011/015 Predicted Afr/Ap 22 Mar-24 Mar 007/008-008/008-006/005
VI. Geomagnetic Activity Probabilities 22 Mar to 24 Mar
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 05% |
| Minor storm | 05% | 05% | 01% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 20% | 20% | 10% |
| Major-severe storm | 20% | 20% | 05% |
All times in UTC
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