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Solar activity report

Report of Solar-Geophysical Activity 2018 Apr 20 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 110 Issued at 2200Z on 20 Apr 2018

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 1 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 Apr, 22 Apr, 23 Apr).
IIA. Geophysical Activity Summary 19-2100Z to 20-2100Z
The geomagnetic field has been at quiet to major storm levels for the past 24 hours. Solar wind speed reached a peak of 637 km/s at 20/1932Z. Total IMF reached 23 nT at 20/0517Z. The maximum southward component of Bz reached -19 nT at 20/0812Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 2168 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at unsettled to minor storm levels on day one (21 Apr), quiet to unsettled levels on day two (22 Apr) and quiet levels on day three (23 Apr).
III. Event Probabilities 21 Apr to 23 Apr
Class M01%01%01%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       20 Apr 073
  Predicted   21 Apr-23 Apr 075/075/075
  90 Day Mean        20 Apr 070

V. Geomagnetic A Indices
  Observed Afr/Ap 19 Apr  002/002
  Estimated     Afr/Ap 20 Apr  029/048
  Predicted    Afr/Ap 21 Apr-23 Apr  019/025-010/010-005/005

VI. Geomagnetic Activity Probabilities 21 Apr to 23 Apr
A. Middle Latitudes
Minor storm25%10%01%
Major-severe storm10%01%01%
B. High Latitudes
Minor storm25%30%20%
Major-severe storm55%35%10%

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