Summary and Forecast

Solar Summary

(last updated 27 Sep 2016 23:30 UT)

Activity 27 Sep: Low Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 27 Sep: 86/29

Solar Forecast

(last updated 27 Sep 2016 23:30 UT)

28 Sep 29 Sep 30 Sep Activity Very low to low Very low to low Very low to low Fadeouts None expected None expected None expected 10.7cm/SSN 85/27 85/27 80/20 COMMENT: The solar activity was at very low levels for the UT day, 27 September. There is still one sunspot region (Region 2597) located at S14W48 and it produced one weak C-class flare (27/0805) and three B-class flares during the last 24 hours. The two day outlook (28-29 September) is for very low solar activity with chance of C-class flares, possibly from Region 2597. No Earth-directed CMEs were observed in the available coronagraph imagery The solar wind speeds were steady around 500 km/s from 27/0000 UT to 27/1600 UT and thereafter continued to trend towards strongly enhanced levels. The current solar wind speed is around 700 km/s. These enhancements in the solar wind speeds are due to the arrival of high speed streams from a large positive polarity coronal hole now taking geoeffective position on the solar disk. The north south component of the Interplanetary Magnetic Field (IMF) fluctuated between -10 and +5 nT. Bt had been steady near 10 nT for most of the UT day and has declined to a weaker value of 5 nT during last few hours of the UT day. The two day outlook (28-29 September) is for the solar winds to further enhance as the coronal effects are expected to persist for few more days. In the previous three rotation, the daily mean solar wind speeds were greater than 500 km/s for at least 6 consecutive days during the passage of this coronal hole. Similar effects are expected in this rotation.

Solar Activity levels are explained in the SWS Solar Terrestrial Glossary.