Viewing archive of Wednesday, 21 December 2016

Solar activity report

Report of Solar-Geophysical Activity 2016 Dec 21 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 356 Issued at 2200Z on 21 Dec 2016

IA. Analysis of Solar Active Regions and Activity from 20-2100Z to 21-2100Z

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 (22 Dec, 23 Dec, 24 Dec).
IIA. Geophysical Activity Summary 20-2100Z to 21-2100Z
The geomagnetic field has been at quiet to major storm levels for the past 24 hours. Solar wind speed reached a peak of 674 km/s at 21/1251Z. Total IMF reached 15 nT at 21/1626Z. The maximum southward component of Bz reached -11 nT at 21/0839Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 506 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at active to minor storm levels on day one (22 Dec) and quiet to active levels on days two and three (23 Dec, 24 Dec).
III. Event Probabilities 22 Dec to 24 Dec
Class M 01%01%01%
Class X 01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       21 Dec 075
  Predicted    22 Dec-24 Dec 075/080/085
  90 Day Mean        21 Dec 081

V. Geomagnetic A Indices
  Observed Afr/Ap 20 Dec  004/004
  Estimated     Afr/Ap 21 Dec  020/028
  Predicted     Afr/Ap 22 Dec-24 Dec  020/030-011/012-010/012

VI. Geomagnetic Activity Probabilities 22 Dec to 24 Dec
A. Middle Latitudes
Minor storm 25%10%10%
Major-severe storm 05%01%01%
B. High Latitudes
Minor storm 25%25%25%
Major-severe storm 60%35%35%

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