Solar Activity

» 24 hr Summary: Solar activity has been at low levels with only C-class flares observed. Most of the activity has come from Regions 4172 (N11W45, Eai/beta-gamma) and 4178 (N09W76, Dsi/beta-gamma). Flux emergence within 4172 has slowed and the interior, as well as the trailing spots have decayed. Consolidation of spots in 4178 increased the size of the leader with its trailing spots in decay. All other regions are fairly simple in their magnetic complexity and have remained quiet.

There were no Earth-directed CMEs in coronagraph imagery.

» Forecast: Solar activity is likely to continue at low levels through 16 August. However, a high chance for isolated M-class flares (R1-2/Minor-Moderate radio blackouts) will remain probable due to the flare potential of Region 4172 and 4178.

Energetic Particle

» 24 hr Summary: Due to the persistent enhancement of particle flux within the coronal hole (CH) high speed stream (HSS) eminating primarily from the large, positive polarity CH in the southern hemisphere, the greater than 2 MeV electron flux surpassed the 1,000 particle flux units (pfu) on both GOES satellites. The GOES-19 satellite observed a peak of 8,355 pfu at 13/1635 UTC and has been on the steady decline since.

The greater than 10 MeV proton flux remained at background.

» Forecast: CH HSS influences are forecast to remain geoeffective through 15 August with waning influences into 16 Aug. In response, the greater than 2 MeV electron flux at geosynchronous orbit is expected to continue to reach high levels (at or above 1,000 pfu) through the forecast period.

The greater than 10 MeV proton flux is expected to remain at background levels through 16 August. There remains a very slight chance (<10%) for radiation storming levels to hit the S1 threshold based on the potential for significant flaring from Regions 4172 and/or 4178 which are moving into a more favorable, geoeffective position in the western hemisphere.

Solar Wind

» 24 hr Summary: Solar wind parameters, as measured at Lagrange point 1 (L1) by the ACE spacecraft, reflected a continued, but weakening positive polarity CH HSS regime. Total field (Bt) remained around 5 nT with the north-south (Bz) component oscillating between +/-5 nT. Solar wind speeds gradually declined from 600 km/s to around 500 km/s. Phi was predominantly in the positive (away from the Sun) solar sector with a few excursions into negative orientation.

» Forecast: Waning influences from the CH HSS are expected through 16 Aug. Solar wind analyses project wind speeds to be down towards 400 km/s by 16 Aug indicating a more nominal wind speed environment.

Geospace

» 24 hr Summary: The geomagnetic field has been at unsettled levels for most of the day, with an isolated late period of active levels.

» Forecast: Current conditions are expected to persist through 15 Aug with mostly quiet conditions thereafter.

-Bri


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