Viewing archive of Wednesday, 20 September 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 Sep 20 2200 UTCPrepared by the NOAA © SWPC and processed by SpaceWeatherLive.com
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 263 Issued at 2200Z on 20 Sep 2017IA. Analysis of Solar Active Regions and Activity from 19-2100Z to 20-2100Z
Solar activity has been at very low levels for the past 24
hours. There are currently 2 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low
with a slight chance for a C-class flare on days one, two, and three (21
Sep, 22 Sep, 23 Sep).
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic
field has been at quiet to unsettled levels for the past 24 hours. Solar
wind speed reached a peak of 533 km/s at 19/2118Z. Total IMF reached 6
nT at 20/2016Z. The maximum southward component of Bz reached -4 nT at
20/1158Z. Electrons greater than 2 MeV at geosynchronous orbit reached a
peak level of 33761 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected
to be at quiet to unsettled levels on days one and three (21 Sep, 23
Sep) and quiet levels on day two (22 Sep).
III. Event Probabilities 21 Sep to 23 Sep
| Class M | 01% | 01% | 01% |
| Class X | 01% | 01% | 01% |
| Proton | 01% | 01% | 01% |
| PCAF | green | ||
IV. Penticton 10.7 cm Flux
Observed 20 Sep 074 Predicted 21 Sep-23 Sep 074/073/075 90 Day Mean 20 Sep 081
V. Geomagnetic A Indices
Observed Afr/Ap 19 Sep 006/008 Estimated Afr/Ap 20 Sep 009/011 Predicted Afr/Ap 21 Sep-23 Sep 007/008-006/005-007/008
VI. Geomagnetic Activity Probabilities 21 Sep to 23 Sep
| A. Middle Latitudes | |||
|---|---|---|---|
| Active | 20% | 10% | 20% |
| Minor storm | 05% | 01% | 05% |
| Major-severe storm | 01% | 01% | 01% |
| B. High Latitudes | |||
|---|---|---|---|
| Active | 15% | 15% | 15% |
| Minor storm | 30% | 20% | 25% |
| Major-severe storm | 30% | 20% | 30% |
All times in UTC
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