Viewing archive of Sunday, 17 December 2023

Solar activity report

Report of Solar-Geophysical Activity 2023 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 2023

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

Solar activity has been at moderate levels for the past 24 hours. The largest solar event of the period was a M1 event observed at 17/2017Z from Region 3514 (N05W94). There are currently 8 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be low with a chance for M-class flares on day one (18 Dec) and expected to be low with a slight chance for an M-class flare on days two and three (19 Dec, 20 Dec).
IIA. Geophysical Activity Summary 16-2100Z to 17-2100Z
The geomagnetic field has been at unsettled to minor storm levels for the past 24 hours. Solar wind speed reached a peak of 565 km/s at 17/0955Z. Total IMF reached 16 nT at 17/1439Z. The maximum southward component of Bz reached -14 nT at 17/1505Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 147 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to minor storm levels on day one (18 Dec) and quiet to active levels on days two and three (19 Dec, 20 Dec).
III. Event Probabilities 18 Dec to 20 Dec
Class M25%10%10%
Class X05%01%01%
IV. Penticton 10.7 cm Flux
  Observed       17 Dec 155
  Predicted   18 Dec-20 Dec 147/145/140
  90 Day Mean        17 Dec 149

V. Geomagnetic A Indices
  Observed Afr/Ap 16 Dec  010/011
  Estimated     Afr/Ap 17 Dec  025/035
  Predicted    Afr/Ap 18 Dec-20 Dec  013/015-013/015-011/012

VI. Geomagnetic Activity Probabilities 18 Dec to 20 Dec
A. Middle Latitudes
Minor storm15%10%10%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm20%20%20%
Major-severe storm20%20%25%

All times in UTC

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