:Issued: 2026 Mar 12 1231 UTC :Product: documentation at http://www.sidc.be/products/meu #--------------------------------------------------------------------# # DAILY BULLETIN ON SOLAR AND GEOMAGNETIC ACTIVITY from the SIDC # # (RWC Belgium) # #--------------------------------------------------------------------# SIDC URSIGRAM 60312 SIDC SOLAR BULLETIN 12 Mar 2026, 1230UT SIDC FORECAST SOLAR FLARES : C-class flares expected, (probability >=50%) GEOMAGNETISM : Quiet (A<20 and K<4) SOLAR PROTONS : Quiet PREDICTIONS FOR 12 Mar 2026 10CM FLUX: 124 / AP: 007 PREDICTIONS FOR 13 Mar 2026 10CM FLUX: 120 / AP: 014 PREDICTIONS FOR 14 Mar 2026 10CM FLUX: 120 / AP: 012 Solar Active Regions and flaring: Solar flaring activity was low over the past 24 hours, with only C-class flares identified. The largest flare was a C4.0 flare (SIDC Flare 7173) peaking on March 12 at 10:46 UTC, which was produced by SIDC Sunspot Group 805 (NOAA Active Region 4384, magnetic type Beta). A total of 9 numbered sunspot groups were identified on the disk over the past 24 hours, all having alpha or beta magnetic configuration. Solar flaring activity is expected to be low over the next 24 hours, with C-class flares very likely and a chance for M-class flares. Coronal mass ejections: No Earth-directed Coronal Mass Ejections (CMEs) have been detected in the available coronagraph images over the past 24 hours. Coronal holes: A large positive polarity transequatorial coronal hole (SIDC Coronal Hole 154) is still crossing the central meridian. The associated high-speed stream is expected to arrive at Earth starting late on March 13. Solar wind: Over the past 24 hours, solar wind parameters (ACE and DSCOVR) were slow, with the solar wind speed reaching values up to 450 km/s. The interplanetary magnetic field remained weak, below 7 nT, with the Bz reaching a minimum value of - 5nT. Slow solar wind conditions are expected over the next 24 hours, with a chance of a weak enhancement from late on March 13 due to the arrival of a high-speed stream from the large positive polarity coronal hole (SIDC Coronal Hole 154). Geomagnetism: Geomagnetic conditions were globally and locally quiet to unsettled (NOAA Kp = 3-, K_bel 2) over the past 24 hours. Mostly quiet to unsettled geomagnetic conditions are expected over the next 24 hours. Proton flux levels: The greater than 10 MeV proton flux, as measured by the GOES-19 satellite, was at background levels over the past 24 hours and is likely to remain so in the next 24 hours. Electron fluxes at GEO: The greater than 2 MeV electron flux measured by GOES-18 and GOES-19 was above the 1000 pfu threshold for the main part of the reporting period. The greater than 2 MeV electron flux may exceed the 1000 pfu threshold over the next 24 hours. The electron fluence was at moderate levels and is expected to remain at these levels over the next 24 hours. TODAY'S ESTIMATED ISN : 104, BASED ON 21 STATIONS. SOLAR INDICES FOR 11 Mar 2026 WOLF NUMBER CATANIA : 125 10CM SOLAR FLUX : 123 AK CHAMBON LA FORET : 012 AK WINGST : 010 ESTIMATED AP : 011 ESTIMATED ISN : 116, BASED ON 20 STATIONS. NOTICEABLE EVENTS SUMMARY DAY BEGIN MAX END LOC XRAY OP 10CM Catania/NOAA RADIO_BURST_TYPES NONE END BT #--------------------------------------------------------------------# # Solar Influences Data analysis Center - RWC Belgium # # Royal Observatory of Belgium # # # # Website http://www.sidc.be. # # E-mail sidc-support@oma.be # # To unsubscribe http://www.sidc.be/registration/unsub.php # # # # Legal notices: # # - Intellectual Property Rights: # # http://www.astro.oma.be/common/internet/en/data-policy-en.pdf # # - Liability Disclaimer: # # http://www.astro.oma.be/common/internet/en/disclaimer-en.pdf # # - Use and processing of your personal information: # # http://www.astro.oma.be/common/internet/en/privacy-policy-en.pdf # #--------------------------------------------------------------------#