Summary and Forecast
Solar Summary
(last updated 23 Apr 2025 23:31 UT)
Activity 23 Apr: R0 Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 23 Apr: 167/121
Solar Forecast
(last updated 23 Apr 2025 23:31 UT)
24 Apr 25 Apr 26 Apr Activity R0-R1 R0-R1 R0-R1 Fadeouts Possible Possible Possible 10.7cm/SSN 160/114 165/119 165/119 COMMENT: Solar activity on UT day 23-Apr was R0. Solar region AR4064 (N11W16, beta-gamma) is currently the largest and most complex region on the visible solar disk. This medium sized region is growing with intermediate spot development evident. Solar region AR4070 (S13E31, beta) is also growing, though this region currently has a more simple bipole magnetic configuration. Solar region AR4062 (S03W40, alpha) is a stable simple monopole. Other regions are quite small and magnetically simple. The largest flare was a C3.9 at 23/1455UT from region AR4064. There are currently eight numbered sunspot regions on the solar disk, with a small spot emerging on disk at N12E57. No solar filament eruptions have been observed. Solar activity is expected to be R0-R1 over 24-26 Apr. No Earth directed CMEs have been observed. A southwest CME was observed from 23/0800UT and is considered to be far side due to the lack of any on disk plasma motion/flare activity. S0 solar radiation storm conditions were observed on UT day 23-Apr. S0 solar radiation storm conditions are expected over 24-26 Apr. The solar wind speed was strong with an initial declining trend then a slight increase toward the end of the UT day and ranged from 458 km/s to 583 km/s and is currently near 534 km/s. The peak total interplanetary field strength (IMF, Bt) was 9 nT and the north-south IMF component range (Bz) was +6 to -4 nT. The solar wind speed is expected to remain mostly elevated over 24-25 Apr, due to a large coronal hole in the southern solar hemisphere. Due to the shape of this coronal hole the solar wind speed may decrease and then subsequently increase again. A small CME impact is possible on late 24-Apr.
Solar Activity levels are explained in the SWS Solar Terrestrial Glossary.
