Viewing archive of Thursday, 28 September 2023

Solar activity report

Report of Solar-Geophysical Activity 2023 Sep 28 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 271 Issued at 2200Z on 28 Sep 2023

IA. Analysis of Solar Active Regions and Activity from 27-2100Z to 28-2100Z

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 28/0907Z from Region 3450 (S19E58). There are currently 7 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 days one, two, and three (29 Sep, 30 Sep, 01 Oct).
IIA. Geophysical Activity Summary 27-2100Z to 28-2100Z
The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 479 km/s at 28/0135Z. Total IMF reached 8 nT at 28/2054Z. The maximum southward component of Bz reached -4 nT at 28/0236Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 1186 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet levels on day one (29 Sep), quiet to active levels on day two (30 Sep) and quiet to unsettled levels on day three (01 Oct).
III. Event Probabilities 29 Sep to 01 Oct
Class M30%30%30%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       28 Sep 148
  Predicted   29 Sep-01 Oct 148/148/145
  90 Day Mean        28 Sep 162

V. Geomagnetic A Indices
  Observed Afr/Ap 27 Sep  012/015
  Estimated     Afr/Ap 28 Sep  006/006
  Predicted    Afr/Ap 29 Sep-01 Oct  005/005-010/012-008/008

VI. Geomagnetic Activity Probabilities 29 Sep to 01 Oct
A. Middle Latitudes
Minor storm01%10%05%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm15%30%25%
Major-severe storm10%40%25%

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