Viewing archive of Sunday, 17 December 2017

Solar activity report

Report of Solar-Geophysical Activity 2017 Dec 17 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 351 Issued at 2200Z on 17 Dec 2017

IA. Analysis of Solar Active Regions and Activity from 16-2100Z to 17-2100Z

Solar activity has been at very low levels for the past 24 hours. There are currently 0 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low on days one, two, and three (18 Dec, 19 Dec, 20 Dec).
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic field has been at quiet to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 666 km/s at 17/1531Z. Total IMF reached 15 nT at 17/1044Z. The maximum southward component of Bz reached -9 nT at 17/0339Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 901 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at unsettled to minor storm levels on days one and two (18 Dec, 19 Dec) and quiet to active levels on day three (20 Dec).
III. Event Probabilities 18 Dec to 20 Dec
Class M 01%01%01%
Class X 01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       17 Dec 071
  Predicted    18 Dec-20 Dec 072/072/072
  90 Day Mean        17 Dec 075

V. Geomagnetic A Indices
  Observed Afr/Ap 16 Dec  003/002
  Estimated     Afr/Ap 17 Dec  019/025
  Predicted     Afr/Ap 18 Dec-20 Dec  017/022-014/020-013/016

VI. Geomagnetic Activity Probabilities 18 Dec to 20 Dec
A. Middle Latitudes
Minor storm 25%20%15%
Major-severe storm 05%05%01%
B. High Latitudes
Minor storm 25%25%30%
Major-severe storm 55%55%45%

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