Date: 2026 Jul 27 0030 UTC
Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
Solar activity reached moderate levels following an impulsive M3.2 (R1-Minor) flare from Region 4494 (S04W04, Dac/beta-delta) at 26/1528 UTC. An associated Type II radio sweep, with an estimated speed of 1057 km/s, was observed at 26/1529 UTC, but no CME has been observed in coronagraph imagery as of this writing. Region 4494 maintained its weak delta configuration, but continued to experience overall decay. Region 4493 (N05W73, Ehi/beta-gamma) exhibited significant loss in its trailer spots as it approached the Western limb. Region 4495 (S02W13, Dao/beta) displayed decent growth and contributed a few low level C-class flares during the period. Region 4496 (N05E33, Dao/beta) initially showed slight growth, but began to decay about halfway through the period. Newly developed Region 4497 (S20W20, Bxo/beta was numbered and remained inactive. No new Earth-directed CMEs were observed in available coronagraph imagery.
Forecast: Solar activity is expected to remain low, with a strong chance for M-class (R1-R2; Minor-Moderate) flares through 29 Jul.Energetic Particle The greater than 2 MeV electron flux reached high levels at 26/1534 UTC, after reaching a peak of 1,159 pfu at 26/1515 UTC. The greater than 10 MeV proton flux was at background values.
Forecast: The greater than 2 MeV electron flux is likely to reach high levels on 27 Jul as CH HSS effects diminish. Moderate are then levels likely on 28-29 Jul. The greater than 10 MeV proton flux is expected to remain at background throughout the period.
Solar wind conditions edged closer to background levels. Total field strength averaged between 2-5 nT, the Bz component varied between +/-4 nT, and solar wind speeds steadily decreased from 520 km/s to 440 km/s. The phi angle remained in a negative orientation.
Forecast: The solar wind environment is expected to be near background levels through most of 27 Jul. Enhancements are likely late in the period with the anticipated weak, flanking influences of a CME from 24 Jul. Enhanced parameters are likely to persist through 28 Jul, then taper off on 29 Jul as CME effects subside.
Forecast: Mostly quiet conditions are expected the first half of 27 Jul. Weak CME influences late on 27 Jul should bring active conditions and a chance for G1 (Minor) storm levels, with conditions likely lasting into 28 Jul. Quiet to unsettled conditions should return by 29 Jul as CME effects diminish.