Summary and Forecast

Solar Summary

(last updated 16 Jun 2026 23:30 UT)

Activity 16 Jun: R0 Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 16 Jun: 113/64

Solar Forecast

(last updated 16 Jun 2026 23:30 UT)

17 Jun 18 Jun 19 Jun Activity R0 R0 R0 Fadeouts None expected None expected None expected 10.7cm/SSN 113/64 115/66 115/66 COMMENT: Solar flare activity on UT day 16-Jun was at the R0 level, with no significant flaring activity. There are currently four numbered active regions (ARs) visible on the solar disk. AR 4465 (N08W36, beta) is the largest region on the disk and has shown mild decay over the UT day. Region 4469 (N08W36, beta) has exhibited mild spot development. Newly numbered region 4470 (N05E70, beta) recently rotated over the eastern limb and appears stable. All other regions are either stable or in decay. Solar flare activity is expected to be at the R0 level over 17-19 Jun. S0 solar radiation storm conditions were observed on UT day 16-Jun. S0 solar radiation storm conditions are expected over 17-19 Jun. No Earth-directed coronal mass ejections (CMEs) have been observed. The solar wind speed on UT day 16-Jun decreased, ranging from 455 to 380 km/s and is currently near 410 km/s. The peak total interplanetary magnetic field strength (IMF, Bt) was 9 nT and the north-south IMF component (Bz) range was -8 to +8 nT. The solar wind speed is expected to remain mildly elevated on 17-Jun, then decline on 18-Jun. A mild increase in the solar wind speed is expected on 19-Jun due to a narrow equatorial coronal hole.

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