Viewing archive of Saturday, 21 October 2017
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 2017 Oct 21 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 294 Issued at 2200Z on 21 Oct 2017IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z
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
20/2328Z from Region 2685 (S10E85). There are currently 1 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 days one, two, and three (22 Oct,
23 Oct, 24 Oct).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 485 km/s at 21/2040Z. Total IMF reached 12
nT at 21/1325Z. The maximum southward component of Bz reached -7 nT at
21/1215Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 3951 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to active levels on day one (22 Oct), quiet levels on day
two (23 Oct) and quiet to minor storm levels on day three (24 Oct).
III. Event Probabilities 22 Oct to 24 Oct
| Class M | 20% | 20% | 20% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 21 Oct 077 Predicted 22 Oct-24 Oct 080/082/084 90 Day Mean 21 Oct 082
V. Geomagnetic A Indices
Observed Afr/Ap 20 Oct 005/008 Estimated Afr/Ap 21 Oct 008/010 Predicted Afr/Ap 22 Oct-24 Oct 009/010-005/005-012/018
VI. Geomagnetic Activity Probabilities 22 Oct to 24 Oct
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 15% | 10% | 30% |
| Minor storm | 05% | 01% | 10% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 30% | 20% | 30% |
| Major-severe storm | 25% | 10% | 45% |
All times in UTC
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