Viewing archive of Friday, 26 August 2011

Solar activity report

Report of Solar-Geophysical Activity 2011 Aug 26 2200 UTC
Prepared by the NOAA © SWPC and processed by

Joint USAF/NOAA Report of Solar and Geophysical Activity

SDF Number 238 Issued at 2200Z on 26 Aug 2011

IA. Analysis of Solar Active Regions and Activity from 25-2100Z to 26-2100Z

Solar activity was at low levels. Region 1271 (N17W69) produced two C-class events during the period, the largest a C2 x-ray event at 26/1313Z. The region continued to exhibit decay in spot count, area and magnetic complexity. Other activity consisted of a B9 x-ray event from Region 1279 (N13E61), observed at 26/1333Z. New Region 1280 (N17E24) emerged on the disk as a simple bi-polar spot group. The remainder of the regions were quiet and stable.
IB. Solar Activity Forecast
Solar activity is expected to be low for the next three days (27 - 29 August). A slight chance for M-class activity exists on days one and two from Region 1271 before the region rotates around the west limb on 28 August.
IIA. Geophysical Activity Summary 25-2100Z to 26-2100Z
The geomagnetic field was quiet. Observations from the ACE spacecraft indicated steady conditions with wind speeds averaging about 400 km/s.
IIB. Geophysical Activity Forecast
The geomagnetic field is expected to remain at quiet levels for day one (27 August). By day two (28 August), activity levels are expected to increase to quiet to unsettled, with isolated active periods, due to a geoeffective, recurrent coronal hole high speed stream. The conditions are expected to persist through day three (29 August).
III. Event Probabilities 27 Aug to 29 Aug
Class M10%05%01%
Class X01%01%01%
IV. Penticton 10.7 cm Flux
  Observed       26 Aug 105
  Predicted   27 Aug-29 Aug  105/100/100
  90 Day Mean        26 Aug 097
V. Geomagnetic A Indices
  Observed Afr/Ap 25 Aug  004/004
  Estimated     Afr/Ap 26 Aug  002/004
  Predicted    Afr/Ap 27 Aug-29 Aug  005/005-007/010-007/008
VI. Geomagnetic Activity Probabilities 27 Aug to 29 Aug
A. Middle Latitudes
Minor storm01%05%05%
Major-severe storm01%01%01%
B. High Latitudes
Minor storm01%15%10%
Major-severe storm01%01%01%

<< Go to daily overview page

Latest news


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!


Space weather facts

Last X-flare:2017/09/10X8.2
Last M-flare:2017/10/20M1.0
Last geomagnetic storm:2019/10/26Kp5 (G1)
Number of spotless days in 2020:11
Current stretch spotless days:9

This day in history*

Solar flares
*since 1994

Social networks