Viewing archive of Friday, 24 September 2021

Solar activity report

Report of Solar-Geophysical Activity 2021 Sep 24 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 267 Issued at 2200Z on 24 Sep 2021

IA. Analysis of Solar Active Regions and Activity from 23-2100Z to 24-2100Z

Solar activity has been at low levels for the past 24 hours. The largest solar event of the period was a C2 event observed at 24/0701Z from Region 2871 (S28E01). There are currently 5 numbered sunspot regions on the disk.
IB. Solar Activity Forecast
Solar activity is expected to be very low with a chance for a C-class flares on days one, two, and three (25 Sep, 26 Sep, 27 Sep).
IIA. Geophysical Activity Summary 23-2100Z to 24-2100Z
The geomagnetic field has been at quiet to unsettled levels for the past 24 hours. Solar wind speed reached a peak of 511 km/s at 24/0830Z. Total IMF reached 9 nT at 23/2309Z. The maximum southward component of Bz reached -6 nT at 24/0635Z. Electrons greater than 2 MeV at geosynchronous orbit reached a peak level of 309 pfu.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to be at quiet to unsettled levels on day one (25 Sep), quiet to minor storm levels on day two (26 Sep) and unsettled to major storm levels on day three (27 Sep).
III. Event Probabilities 25 Sep to 27 Sep
Class M05%05%05%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       24 Sep 088
  Predicted   25 Sep-27 Sep 088/086/082
  90 Day Mean        24 Sep 082

V. Geomagnetic A Indices
  Observed Afr/Ap 23 Sep  010/008
  Estimated     Afr/Ap 24 Sep  007/010
  Predicted    Afr/Ap 25 Sep-27 Sep  009/010-011/018-020/028

VI. Geomagnetic Activity Probabilities 25 Sep to 27 Sep
A. Middle Latitudes
Minor storm10%35%40%
Major-severe storm01%10%20%
B. High Latitudes
Minor storm25%25%20%
Major-severe storm35%70%75%

All times in UTC

<< Go to daily overview page


A lot of people come to SpaceWeatherLive to follow the Sun's activity or if there is aurora to be seen, but with more traffic comes higher server costs. Consider a donation if you enjoy SpaceWeatherLive so we can keep the website online!

Support SpaceWeatherLive with our merchandise
Check out our merchandise

Latest alerts

Get instant alerts!

Space weather facts

Last X-flare2024/05/29X1.45
Last M-flare2024/05/30M1.0
Last geomagnetic storm2024/05/17Kp6 (G2)
Spotless days
Last spotless day2022/06/08
Monthly mean Sunspot Number
April 2024136.5 +31.6
May 2024146.7 +10.2
Last 30 days146.7 +5.6

This day in history*

Solar flares
*since 1994

Social networks