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Solar activity report

Report of Solar-Geophysical Activity 2017 Apr 23 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 113 Issued at 2200Z on 23 Apr 2017

IA. Analysis of Solar Active Regions and Activity from 22-2100Z to 23-2100Z

Solar activity has been at very low levels for the past 24 hours. There are currently 3 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 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 active to major storm levels for the past 24 hours. Solar wind speed reached a peak of 813 km/s at 23/2023Z. Total IMF reached 9 nT at 23/0406Z. The maximum southward component of Bz reached -7 nT at 23/0351Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 20544 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at active to minor storm levels on day one (24 Apr) and unsettled to minor storm levels on days two and three (25 Apr, 26 Apr).
III. Event Probabilities 24 Apr to 26 Apr
Class M01%01%01%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       23 Apr 083
  Predicted   24 Apr-26 Apr 084/084/084
  90 Day Mean        23 Apr 078

V. Geomagnetic A Indices
  Observed Afr/Ap 22 Apr  037/061
  Estimated     Afr/Ap 23 Apr  030/044
  Predicted    Afr/Ap 24 Apr-26 Apr  023/030-015/020-015/020

VI. Geomagnetic Activity Probabilities 24 Apr to 26 Apr
A. Middle Latitudes
Minor storm25%25%25%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm25%25%25%
Major-severe storm65%60%60%

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