Moderate M1.6 solar flare erupts at 09:57 UTC on August 21, 2026

A moderate M1.6 solar flare erupted at 09:57 UTC on August 21, 2026.

Today’s flares include several C-class solar flares. Flares and their start, peak, and end times are as follows: C2.4 at 00:25 UTC (region 4507), C4.1 at 02:01 UTC (region 4507), C6.7 at 02:20 UTC (region 4507), C1.3 at 03:52 UTC (region 4513), C1.5 at 05:09 UTC (region 4513), C1.8 at 05:52 UTC (region 4513), and C6.2 at 06:35 UTC (region 4513). No X- or M-class events are confirmed during this timeframe in the event data provided.

In 24 hours to 00:30 UTC on August 21, solar activity reached moderate levels. The most significant event was an M8.1 flare at 11:42 UTC on August 20. Additional minor M-class flares (M1.8 and M2.9) also occurred on August 20. No Earth-directed coronal mass ejections were observed.

Solar activity is expected to be at low levels over August 21–23, with a chance for isolated M-class flares (R1–R2/Minor–Moderate).

Active sunspot regions presently observed on the Earth-facing solar disk include AR 4506 (N12W0*, Beta), AR 4507 (N04W82, Beta-Gamma), AR 4508 (N09W50, Alpha), AR 4510 (N12W0*, Beta), AR 4513 (N04E69, Beta), and AR 4514 (S10W56, Beta).

Over the past 24 hours, the greater than 2 MeV electron flux at geosynchronous orbit remained at normal to moderate levels. The greater than 10 MeV proton flux remained at background levels. The greater than 2 MeV electron flux is likely to exceed 1 000 pfu on August 21 and remain high through August 23 due to coronal hole high speed stream influences. The greater than 10 MeV proton flux is expected to remain at background levels through August 23.

Solar wind parameters continued to reflect the waning influence of a negative polarity coronal hole high speed stream. Total magnetic field strength was at or below 6 nT, with the Bz component reaching as far south as -5 nT. Solar wind speeds slowly declined, with peak speeds near 600 km/s and lows near 500 km/s by the end of the period. Solar wind is expected to continue showing waning coronal hole influences through August 23.

The geomagnetic field was quiet to unsettled during the reporting period. Geomagnetic activity is likely to reach active levels over August 20–22 as the ongoing coronal hole high speed stream subsides, with unsettled levels likely on August 23.