Viewing archive of Wednesday, 31 December 2025

Solar activity report

Report of Solar-Geophysical Activity 2025 Dec 31 2200 UTC
Prepared by the NOAA © SWPC and processed by SpaceWeatherLive.com

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 365 Issued at 2200Z on 31 Dec 2025

IA. Analysis of Solar Active Regions and Activity from 30-2100Z to 31-2100Z

Solar activity has been at high levels for the past 24 hours. There are currently 7 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is likely to be moderate with a slight chance for an X-class flare on days one, two, and three (01 Jan, 02 Jan, 03 Jan).
IIA. Geophysical Activity Summary 30-2100Z to 31-2100Z
The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 616 km/s at 31/1506Z. Total IMF reached 12 nT at 31/1458Z. The maximum southward component of Bz reached -6 nT at 31/1158Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 3898 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to minor storm levels on days one and two (01 Jan, 02 Jan) and unsettled to major storm levels on day three (03 Jan). Protons have a chance of crossing threshold on day one (01 Jan), have a slight chance of crossing threshold on day two (02 Jan) and have a slight chance of crossing threshold on day three (03 Jan).
III. Event Probabilities 01 Jan to 03 Jan
Class M55%55%55%
Class X20%20%20%
Proton40%20%10%
PCAFgreen
IV. Penticton 10.7 cm Flux
  Observed       31 Dec 171
  Predicted   01 Jan-03 Jan 170/165/160
  90 Day Mean        31 Dec 147

V. Geomagnetic A Indices
  Observed Afr/Ap 30 Dec  005/008
  Estimated     Afr/Ap 31 Dec  007/007
  Predicted    Afr/Ap 01 Jan-03 Jan  014/018-014/016-028/042

VI. Geomagnetic Activity Probabilities 01 Jan to 03 Jan
A. Middle Latitudes
Active40%40%30%
Minor storm30%30%40%
Major-severe storm05%05%25%
B. High Latitudes
Active05%05%05%
Minor storm20%20%15%
Major-severe storm65%65%85%

All times in UTC

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