Viewing archive of Thursday, 23 April 2015
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 2015 Apr 23 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 113 Issued at 2200Z on 23 Apr 2015IA. Analysis of Solar Active Regions and Activity from 22-2100Z to 23-2100Z
Solar activity has been at moderate levels for the past 24
hours. The largest solar event of the period was a M1 event observed at
23/1007Z from Region 2322 (just beyond west limb). There are currently 8
numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with
a slight chance for an M-class flare on days one, two, and three (24
Apr, 25 Apr, 26 Apr).
IIA. Geophysical Activity Summary 22-2100Z to 23-2100Z
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
555 km/s at 22/2319Z. Total IMF reached 6 nT at 22/2210Z. The maximum
southward component of Bz reached -4 nT at 22/2138Z. Electrons greater
than 2 MeV at geosynchronous orbit reached a peak level of 955 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be predominantly quiet to unsettled for the next three days (24-26
Apr).
III. Event Probabilities 24 Apr to 26 Apr
| Class M | 20% | 20% | 20% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 23 Apr 141 Predicted 24 Apr-26 Apr 135/130/125 90 Day Mean 23 Apr 131
V. Geomagnetic A Indices
Observed Afr/Ap 22 Apr 009/011 Estimated Afr/Ap 23 Apr 009/010 Predicted Afr/Ap 24 Apr-26 Apr 007/008-009/012-007/008
VI. Geomagnetic Activity Probabilities 24 Apr to 26 Apr
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 25% | 15% |
| Minor storm | 05% | 05% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 20% | 15% |
| Minor storm | 25% | 30% | 25% |
| Major-severe storm | 20% | 30% | 20% |
All times in UTC
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