Summary and Forecast
Solar Summary
(last updated 15 Mar 2026 23:30 UT)
Activity 15 Mar: R1 Flares Max Fadeout Freq. Sectors M1.0 0939UT possible lower Mid East/Indian Observed 10.7 cm flux/Equivalent Sunspot Number for 15 Mar: 109/59
Solar Forecast
(last updated 15 Mar 2026 23:30 UT)
16 Mar 17 Mar 18 Mar Activity R0,chance R1 R0,chance R1 R0,chance R1 Fadeouts Possible Possible Possible 10.7cm/SSN 108/58 108/58 105/54 COMMENT: Solar activity on UT day 15-Mar was R1 due to an M1.0 flare from AR4392 (S15E34, gamma). Minor localised on disk plasma motion was observed with this flare. The small spots surrounding this regions main spot continue to slowly grow. This medium sized region is currently the largest of the on disk regions. Small solar region AR4395 (S05E45, beta) which was growing rapidly yesterday has now slowed in growth. Another small new region AR4396 (N21E55, beta) has emerged and is currently growing. There are currently six numbered regions on the solar disk, most of which are small. All other sunspot groups are either stable or in decay. Solar activity over 16-18 Mar is expected to be R0, chance R1. No Earth-directed CMEs were observed on UT day 15-Mar. A very faint and narrow southeast CME was observed in LASCO C2 imagery from 15/1112UT possibly following the M1.0 flare. This CME is not considered significant. A northeast CME was observed from 15/1812UT which could not be correlated to on disk activity. S0 solar radiation storm conditions were observed on UT day 15-Mar. S0 solar radiation storm conditions are expected over 16-18 Mar. A large, narrow coronal hole spans from the western solar hemisphere and back across the southern solar hemisphere. On UT day 15-Mar the solar wind speed was strong with a slowly declining trend due to the reducing influence of the wind stream from this coronal hole. The solar wind speed ranged from 680-613 km/s. The solar wind speed is currently at 613 km/s. The peak total interplanetary field strength (IMF, Bt) was 6 nT and the north-south IMF component range (Bz) was +5 to -5 nT. The Bz component fluctuated mildly southward during the UT day. The solar wind is expected to continue to remain elevated on 16-Mar, with an ongoing slow declining trend. The possible weak glancing blow CME arrival on 15-Mar did not eventuate. The GOES geosynchronous 2MeV electron flux is currently elevated above 1000 particles/(cm2 s sr). Elevated electron flux is statistically associated with an increased risk of geosynchronous orbiting satellite operational anomalies.
Solar Activity levels are explained in the SWS Solar Terrestrial Glossary.
