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Solar activity report

Report of Solar-Geophysical Activity 2017 Apr 20 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 110 Issued at 2200Z on 20 Apr 2017

IA. 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 chance for a C-class flares and a slight chance for an M-class flare on days one, two, and three (21 Apr, 22 Apr, 23 Apr).
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic field has been at unsettled to major storm levels for the past 24 hours. Solar wind speed reached a peak of 657 km/s at 20/1056Z. Total IMF reached 16 nT at 19/2117Z. The maximum southward component of Bz reached -12 nT at 20/0005Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 546 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to active levels on day one (21 Apr), quiet to unsettled levels on day two (22 Apr) and active to major storm levels on day three (23 Apr).
III. Event Probabilities 21 Apr to 23 Apr
Class M 10%10%10%
Class X 01%01%01%
Proton01%01%01%
PCAFgreen
IV. Penticton 10.7 cm Flux
  Observed       20 Apr 081
  Predicted    21 Apr-23 Apr 085/085/085
  90 Day Mean        20 Apr 078

V. Geomagnetic A Indices
  Observed Afr/Ap 19 Apr  012/017
  Estimated     Afr/Ap 20 Apr  024/035
  Predicted     Afr/Ap 21 Apr-23 Apr  010/012-007/008-028/040

VI. Geomagnetic Activity Probabilities 21 Apr to 23 Apr
A. Middle Latitudes
Active30%20%30%
Minor storm 05%05%40%
Major-severe storm 01%01%15%
B. High Latitudes
Active15%20%05%
Minor storm 30%30%20%
Major-severe storm 35%25%75%

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