Summary and Forecast

Solar Summary

(last updated 12 May 2024 23:30 UT)

Activity 12 May: R3 Flares Max Fadeout Freq. Sectors M3.2 0045UT possible lower West Pacific M2.4 0552UT possible lower E. Asia/Aust. M1.6 1241UT possible lower European M1.0 1347UT possible lower European M1.5 1356UT possible lower European X1.0 1626UT probable all South American/ Atlantic M4.8 2032UT possible lower East Pacific/ North American M1.1 2206UT possible lower East Pacific/ North American M1.0 2310UT possible lower West Pacific Observed 10.7 cm flux/Equivalent Sunspot Number for 12 May: 222/172

Solar Forecast

(last updated 12 May 2024 23:30 UT)

13 May 14 May 15 May Activity R2-R3 R2-R3 R1-R2 Fadeouts Probable Probable Probable 10.7cm/SSN 220/170 215/165 200/152 COMMENT: Solar activity on UT day 12-May was at the R3 level due an X1 flare from the large solar region AR3664(S19W67, beta-gamma-delta). This region also produced the M4.8, M3.2, M2.4 and two M1 flares and is now approaching the south west solar limb. An R1(M1.0) flare was from solar region AR3679(S09E78, beta) a very small region that has recently rotated onto the solar disk. Small solar regions AR3676(S12E19, beta-gamma) and AR3675(S15W37, beta) have shown rapid growth in the past 24 hours. Small solar region AR3671(N23W05, beta) has shown some growth. There are currently twelve numbered regions on the solar disk. All other sunspot regions are either stable or in decay. Solar activity is expected to be at R2-R3 levels over 13-14 May, with a decline in activity likely on 15-May to R1-R2. Solar flare activity is expected to become less frequent after the departure of AR3664. The GOES solar proton flux has declined and is now at S0. Solar radiation storm conditions are expected to be at S0, with the chance of S1 over 13-14 May. No significantly Earth directed CMEs have been observed in the last 24 hours. In LASCO C2 imagery a southwest directed CME was observed from 12/0348UT which could not be correlated with today's flare activity and is currently considered a far side event. An extremely faint and narrow west directed CME is visible from 12/1136UT and is not considered significant. The solar wind environment on 12-May overall has declined from its recently extremely enhanced state. A weak shock was observed at 12/0856UT which very mildly enhanced the interplanetary magnetic field post shock arrival. This shock was weaker than expected. There is the possibility of a CME arrival over the next 24-48 hours, but confidence is now low on any significant CME arrival. The ACE EPAM low energy ion channel which can be used as a precursor for CME arrival is currently not showing a steady increasing trend. The solar ranged from 740 to 990 km/s and is currently near 820 km/s. The peak total interplanetary field strength (IMF, Bt) was 12 nT and the north-south IMF component (Bz) range was +8 to -6 nT, with Bz mildly southward during the interval 12/1941-2154UT. Two small coronal holes are visible in the northwest and southeast solar quadrant.

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