Summary and Forecast

Solar Summary

(last updated 01 Jun 2026 23:30 UT)

Activity 01 Jun: R0 Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 01 Jun: 132/86

Solar Forecast

(last updated 01 Jun 2026 23:30 UT)

02 Jun 03 Jun 04 Jun Activity R0, chance of R1 R0, chance of R1 R0, chance of R1 Fadeouts None expected None expected None expected 10.7cm/SSN 128/81 130/84 127/80 COMMENT: Solar flare activity on UT day 01-Jun was at the R0 level, with no significant flaring activity. There are currently nine numbered active regions (ARs) visible on the solar disk. AR 4455 (N15E12, beta) is the largest region on the disk and has shown minor spot development in its trailer spots over the UT day. AR 4446 (S13N48, beta) has exhibited development in its trailer spots. Newly numbered region 4458 (S09E20, beta) recently appeared on the solar disk and has shown rapid spot development. A second newly numbered region 4459 (N11E60, beta) recently appeared and has shown mild growth. All other regions are either stable or in decay. Solar flare activity is expected to be at the R0 level over 02-04 Jun, with a chance of R1. S0 solar radiation storm conditions were observed on UT day 01-Jun. S0 solar radiation storm conditions are expected over 02-04 Jun. No Earth-directed coronal mass ejections (CMEs) have been observed. The solar wind speed on UT day 01-Jun decreased, ranging from 460 to 385 km/s and is currently near 395 km/s. The peak total interplanetary magnetic field strength (IMF, Bt) was 7 nT and the north-south IMF component (Bz) range was -7 to 0 nT. Southward IMF conditions were observed for most of the UT day, with the strongest observed over the interval 01/1212-1546UT. The solar wind speed is expected to remain near background levels on 02-Jun, then increase late on 03-Jun due to coronal hole high speed wind stream effects from a small equatorial coronal hole.

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