Solar Activity

» 24 hr Summary: Solar activity reached moderate levels due to an M1.7 flare at 24/1936 UTC from Region 4513 (N04E10, Ekc/beta-gamma-delta). EUV dimming was observed in SUVI 195 imagery at 24/1950 UTC associated with the flare. Analysis of potential CMEs will be conducted as imagery becomes available.

Slight growth and separation occurred in Region 4513 along with motion across its delta magnetic configuration. Slight growth occurred in Regions 4516 (N17W55, Cao/beta) and 4517 (N10W03, Dao/beta). Region 4515 (S08E23, Hsx/alpha) was stable.

» Forecast: Solar activity is expected to be at low levels, with a chance for M-flares (R1-R2/Minor-Moderate) and a slight chance for an X-flare (R3/Strong or greater) over 25-27 Aug.

Energetic Particle

» 24 hr Summary: The greater than 2 MeV electron flux reached high levels with a peak flux of 1,640 pfu observed at 24/1610 UTC. The greater than 10 MeV proton flux remained elevated, but below S1 (Minor) levels, ranging from 2-4 pfu throughout the period.

» Forecast: The greater than 2 MeV electron flux is expected to reach high levels on 24-27 Aug. There is a chance for the greater than 10 MeV proton flux to reach S1 (Minor) levels on 25 Aug due to the aforementioned M1.7 flare. The ACE/SIS instrument showed a slight increase in the greater than 10 and 30 MeV levels at L1. A decrease to slight chance for S1 levels is expected on 26-27 Aug.

Solar Wind

» 24 hr Summary: Solar wind parameters were at nominal levels with solar wind speed averaging around 365 km/s. Total field ranged from 4-6 nT while the Bz component was between +/-4 nT. Phi angle was predominantly negative.

» Forecast: Nominal solar wind conditions are expected through approximately midday on 27 Aug. An enhancement is expected by mid to late on 27 Aug due to the onset of positive polarity CH HSS conditions. Solar wind speeds are likely to be more enhanced than the previous rotation due to a more developed northerly extension of the CH. Solar wind speeds in the 500-600 km/s range are likely.

Geospace

» 24 hr Summary: The geomagnetic field was at quiet to unsettled levels under an ambient solar wind environment.

» Forecast: The geomagnetic field is expected to be mostly quiet through midday on 27 Aug under ambient solar wind conditions. By mid to late on 27 Aug, Unsettled to active levels are expected, with a chance for G1 (Minor) storm levels, due to the onset of CH HSS conditions.


Prepared by:
The U.S. Dept. of Commerce, NOAA, SWPC