:Issued: 2025 Nov 16 1248 UTC :Product: documentation at http://www.sidc.be/products/meu #--------------------------------------------------------------------# # DAILY BULLETIN ON SOLAR AND GEOMAGNETIC ACTIVITY from the SIDC # # (RWC Belgium) # #--------------------------------------------------------------------# SIDC URSIGRAM 51116 SIDC SOLAR BULLETIN 16 Nov 2025, 1247UT SIDC FORECAST SOLAR FLARES : C-class flares expected, (probability >=50%) GEOMAGNETISM : Active conditions expected (A>=20 or K=4) SOLAR PROTONS : Warning condition (activity levels expected to increase, but no numeric forecast given) PREDICTIONS FOR 16 Nov 2025 10CM FLUX: 130 / AP: 019 PREDICTIONS FOR 17 Nov 2025 10CM FLUX: 130 / AP: 024 PREDICTIONS FOR 18 Nov 2025 10CM FLUX: 130 / AP: 017 Solar Active Regions and flaring: Solar flaring activity was moderate over the past 24 hours, with one M-class flare identified. The largest was an M3.1 flare (SIDC Flare 6105) that peaked at 08:17 UTC on 16 Nov, produced by SIDC Sunspot Group 687 (NOAA Active Region 4274). SIDC Sunspot Group 687 has rotated past the west limb and is currently at N24W94. Other regions show very low to no flaring activity; therefore, overall flaring is expected to be low over the next 24 hours. Although just beyond the west limb, C-class flares remain likely, with a small chance of an M-class event coming from SIDC Sunspot Group 687 (NOAA Active Region 4274). Coronal mass ejections: A large south-southeast coronal mass ejection has been detected with a relatively slow speed as estimated in the plane of the sky. The source is believed to be on the far side of the Sun, so this CME is likely back-sided. No Earth-directed CMEs were identified in SOHO/LASCO coronagraph images during the past 24 hours. Coronal holes: SIDC Coronal Hole 126 (mid-latitude coronal hole with a negative polarity) first reached the central meridian on November 13 and is now positioned on the western side of the Sun. Solar wind: During the past 24 hours the solar wind stayed moderately fast, with a clear enhancement around 01:00 UTC on 16 November consistent with the expected glancing passage of the coronal mass ejection (SIDC CME 601). Around 01:00 UTC on 16 November, the speed rose from about 540 km/s to above 600 km/s, then increased further to a peak near 727 km/s and is now around 650 to 680 km/s. The total interplanetary magnetic field (IMF), Bt, climbed from about 5 nT to 10 nT with the initial step, then reached a maximum near 17.7 nT around 05:30 UTC. The north-south component of the IMF, Bz, ranged between about -7.5 nT and +15.5 nT, predominantly positive with only brief southward intervals. Over the next 24 hours speeds should gradually decline but remain above background as the CME influence wanes and high-speed flow from SIDC Coronal Hole 126 (mid-latitude, negative polarity) begins to affect near-Earth conditions later today. Geomagnetism: Global activity increased to unsettled with a brief active interval. NOAA Kp ranged from 1 to 4, peaking at Kp=4 between 00:00 and 03:00 UTC on 16 Nov. This likely reflects a prolonged period of southward Bz combined with a sudden increase in the total interplanetary magnetic field around 01:00 UTC associated with the glancing blow from the coronal mass ejection (SIDC CME 601). In Belgium, K BEL was mostly 1 to 3. Over the next 24 hours, conditions should range between quiet and unsettled with occasional active intervals. High-speed streams from SIDC Coronal Hole 126 (mid-latitude, negative polarity) later today may prolong unsettled to active conditions with a chance of isolated minor storm periods if Bz turns south. Proton flux levels: During the past 24 hours the greater than 10 MeV proton flux measured by GOES-19 was below the 10 pfu threshold and continut to return to its background levels. Further enhancements remain possible, particularly if the SIDC Sunspot Group 687 (NOAA Active Region 4274) produces additional eruptions. Electron fluxes at GEO: The greater than 2 MeV electron flux measured by GOES 18 and GOES 19 was below the 1000 pfu threshold. The greater than 2 MeV electron flux is expected to remain below the 1000 pfu threshold over the next 24 hours. The 24-hour electron fluence was at normal levels and is expected to be at normal levels over the next 24 hours. TODAY'S ESTIMATED ISN : 084, BASED ON 04 STATIONS. SOLAR INDICES FOR 15 Nov 2025 WOLF NUMBER CATANIA : /// 10CM SOLAR FLUX : 132 AK CHAMBON LA FORET : 021 AK WINGST : 012 ESTIMATED AP : 010 ESTIMATED ISN : 104, BASED ON 12 STATIONS. NOTICEABLE EVENTS SUMMARY DAY BEGIN MAX END LOC XRAY OP 10CM Catania/NOAA RADIO_BURST_TYPES 16 0749 0817 0832 ////// M3.1 89/4274 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 # #--------------------------------------------------------------------#