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Here is the current forecast discussion on space weather and geophysical activity, issued 2015 Aug 20 1230 UTC.
Solar Activity
24 hr Summary: Solar activity reached low levels. Region 2403 (S12E44, Dac/beta-gamma) continued to exhibit slight growth in its leader and intermediate spots and produced three low-level C-class flares during the period. The largest flare was a long duration C3/2n flare at 20/0526 UTC. Region 2401 (S10W36, Dai/beta) showed decay in its leader and trailer spots and was relatively inactive.
An approximately 11 degree long filament was observed in SDO/AIA 304 imagery, lifting off the southeast limb near S25E54 from approximately 19/1309 - 1700 UTC. Coronal dimming could also been seen on SDO/AIA 193 imagery just south of Region 2403, at approximately the same time. Forecaster analysis indicated that the ejection was off of the Sun-Earth line. No Earth-directed CMEs were detected in available LASCO coronagraph imagery.
Forecast: As Region 2403 continues to increase in size and magnetic complexity, solar activity is likely to be low with a slight chance for an M-class (R1-R2, Minor-Moderate) flare for days one through three (21-23 Aug).
Energetic Particle
24 hr Summary: The greater than 2 MeV electron flux reached high levels with a maximum of 3,900 pfu at 19/1805 UTC. The greater than 10 MeV proton flux was at background levels throughout the period.
Forecast: The greater than 2 MeV electron flux is expected to be at moderate to high levels over the next three days (20-22 Aug). The greater than 10 MeV proton flux is expected to remain at background levels (Below S1-Minor) throughout the forecast period.
Solar Wind
24 hr Summary: Solar wind parameters, measured by the ACE spacecraft, were enhanced throughout the period, yet most values remained fairly steady or exhibited slight increases. Solar wind speeds fluctuated throughout the period in the 470-520 km/s range. The IMF total field fluctuated between 4 and 9 nT, the Bz component varied between +/- 8 nT, and the phi angle remained in a predominantly positive orientation during the period.
Forecast: The solar wind environment is expected to remain slightly disturbed the first half of day one (20 Aug), before the positive polarity coronal hole (CH) in the north moves into a potentially geoeffective position. As the CH influence increases, slight enhancements could be reflected in the wind speeds and mag field by mid to late day. By day two (21 Aug), CH high speed stream (HSS) effects should persist, keeping the solar wind environment slightly agitated through day three (22 Aug).
Geospace
24 hr Summary: The geomagnetic field was predominantly at quiet to unsettled levels with an isolated period of active conditions.
Forecast: The geomagnetic field is expected to be at quiet to active levels on day one (20 Aug) as the positive polarity CH in the north moves into a potentially geoeffective position. Quiet to unsettled levels are expected on days two and three (21 - 22 Aug) as CH HSS effects begin to wane.
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![Today's Space Weather Forecast Discussion - 2015 Aug 20 20:07 UTC]()
Live data: SunSpotWatch.com
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