Summary and Forecast

Solar Summary

(last updated 12 May 2026 23:31 UT)

Activity 12 May: R0 Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 12 May: 111/62

Solar Forecast

(last updated 12 May 2026 23:31 UT)

13 May 14 May 15 May Activity R1, chance of R2 R1 R1 Fadeouts Possible Possible Possible 10.7cm/SSN 110/60 110/60 110/60 COMMENT: Solar flare activity on UT day 12-May was at the R0 level, with no significant flares observed. There are currently four active regions on the visible solar disk, with Active Region (AR) 4432 (N12W76, beta) the largest. This region has shown some minor decay, and will likely rotate off the visible solar disk over the next 24 hours. All other regions have appeared largely stable during 12-May. Solar flare activity is forecast to be at the R1 level, with a chance of R2 on 13-May. This will decline to R1 conditions on 14-15 May as AR 4432 rotates off the visible solar disk. S0 solar proton conditions were observed throughout UT day 12-May. S0 conditions are expected through 13-15 May. No geoeffective coronal mass ejections (CMEs) were observed over 12-May. An eruption near the south-eastern limb was visible in SDO/AIA 304A imaging at 11/2100UT. A low-velocity south-east-directed CME associated with this event was observed in SOHO/LASCO from 12/0126UT. This event has been modelled to miss the Earth. The solar wind speed was consistent with background conditions on 12-May, broadly ranging between 340 and 390 km/s throughout the day. The interplanetary magnetic field strength (IMF, Bt) peaked at 7 nT, with the north-south component (Bz) ranging between -5 and +5 nT over the UT day. The solar wind will remain at background values over 13-14 May before increasing on 15-May due to a high speed wind stream from an equatorial coronal hole that will connect with Earth.

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