Moderate M1.0 solar flare erupts at 18:51 UTC on August 19, 2026

A moderate M1.0 solar flare erupted at 18:51 UTC on August 19, 2026.

Today’s flares include C3.9 (max at 00:37 UTC, AR 4507), C2.0 (max at 02:31 UTC, AR 4507), C3.9 (max at 02:56 UTC, AR 4507), C3.0 (max at 03:46 UTC), C5.0 (max at 04:54 UTC), C1.3 (max at 06:36 UTC, AR 4507), C2.7 (max at 08:44 UTC, AR 4507), C2.0 (max at 09:10 UTC, AR 4507), and C1.3 (max at 11:05 UTC, AR 4507).

In 24 hours to 11:55 UTC on August 19, solar activity continued at low levels, with most C-class flares originating at AR 4507. The largest flare was a C5.0 at 04:54 UTC. Most visible active regions showed some decay.

Solar activity is expected to continue at low levels from August 19 to 21, with a chance for M-class flares (R1 – Minor to R2 – Moderate).

Active sunspot regions presently observed on the Earth-facing solar disk include AR 4506 (N12W72 – Beta), AR 4507 (N04W55 – Beta-Gamma-Delta), AR 4508 (N08W23 – Beta), and AR 4510 (N12W81 – Beta).

Over the past 24 hours, electron flux at geosynchronous orbit was at normal to moderate levels, and proton flux stayed at background levels. The greater than 2 MeV electron flux is likely to remain at low to moderate levels through August 20. High levels are likely by August 21 due to coronal hole high-speed stream influences. The greater than 10 MeV proton flux is expected to remain at background levels through August 20.

Solar wind conditions showed a waning corotating interaction region with dominant negative polarity coronal hole high-speed stream effects near Earth. Total magnetic field strength dropped from 15 nT to 5–10 nT after 19:00 UTC on August 18, with solar wind speeds increasing to 550–600 km/s. The phi angle remained predominantly negative. Solar wind parameters are likely to continue to reflect high-speed streams from negative polarity coronal holes through August 21.

The geomagnetic field ranged from quiet to G1 – Minor storm levels, with G1 levels during 18:00–21:00 UTC on August 18 and 03:00–06:00 UTC on August 19 due to intervals of persistent negative Bz. The geomagnetic field is likely to reach G1 – Minor levels again until the end of August 19 due to coronal hole high-speed stream influence. Mostly active conditions are likely over August 20 to 21 during the waning phase of the high-speed stream.