Summary and Forecast

Solar Summary

(last updated 19 Aug 2026 23:30 UT)

Activity 19 Aug: R1 Flares Max Fadeout Freq. Sectors M1.0 1851UT possible lower E. Asia/Aust. Observed 10.7 cm flux/Equivalent Sunspot Number for 19 Aug: 126/79

Solar Forecast

(last updated 19 Aug 2026 23:30 UT)

20 Aug 21 Aug 22 Aug Activity R0-R1 R0-R1 R0-R1 Fadeouts Possible Possible Possible 10.7cm/SSN 125/78 125/78 125/78 COMMENT: Solar flare activity on UT day 19-Aug was at the R1 level due to an M1.0 flare at 19/1851UT produced by Active Region (AR) 4513 (N04E75, beta) near the eastern limb. There are currently four numbered sunspot regions visible on the solar disk and one unnumbered region. AR 4507 (N05W66, beta) is the largest region on the disk and has shown decay in its trailer spots. Region 4513 recently rotated over the eastern limb and appears stable. An unnumbered region recently appeared near S12W41 (beta) and has shown spot growth. All other regions are either stable or in decay. Solar flare activity is expected to be at R0-R1 levels over 20-22 Aug due to the observed flare activity from AR 4513. S0 solar radiation storm conditions were observed on UT day 19-Aug. S0 solar radiation storm conditions are expected over 20-22 Aug. No Earth-directed coronal mass ejections (CMEs) have been observed. The solar wind speed on UT day 19-Aug was mostly steady, ranging between 535 and 615 km/s, and is currently near 590 km/s. The peak total interplanetary magnetic field strength (IMF, Bt) was 10 nT and the north-south IMF component (Bz) range was -8 to +7 nT. The solar wind speed is expected to remain elevated over 20-22 Aug due to coronal hole high speed wind stream effects from a northern hemisphere coronal hole.

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