:Issued: 2025 Aug 03 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 50803 SIDC SOLAR BULLETIN 03 Aug 2025, 1230UT SIDC FORECAST SOLAR FLARES : M-class flares expected (probability >=50%) GEOMAGNETISM : Quiet (A<20 and K<4) SOLAR PROTONS : Quiet PREDICTIONS FOR 03 Aug 2025 10CM FLUX: 148 / AP: 005 PREDICTIONS FOR 04 Aug 2025 10CM FLUX: 150 / AP: 008 PREDICTIONS FOR 05 Aug 2025 10CM FLUX: 153 / AP: 016 Solar Active Regions and flaring: Solar flaring activity over the past 24 hours remained at low levels with background C-class flaring. A total of 9 numbered sunspot groups were identified on the visible solar disk. Most of the flaring activity was produced by SIDC Sunspot Group 585 (NOAA Active Region 4167) and SIDC Sunspot Group 588 (NOAA Active Region 4168), which have both increased the complexity of their underlying magnetic field and have been classified as magnetic type beta-gamma-delta. The remaining regions have either shown signs of decay or remained simple and inactive. Isolated low C-class flaring was produced by SIDC 570 (NOAA 4153) from the west limb and by a region behind the north-east limb. The strongest activity was a C4.3 flare (SIDC Flare 5012) with peak time 02:45 UTC on Aug 03 produced by SIDC Sunspot Group 588. The solar flaring activity is expected to reach moderate levels over the next 24 hours with 75% chances for M-class flaring and small chances for X-class flares. Coronal mass ejections: No Earth-directed coronal mass ejection (CMEs) have been detected in the available coronagraph imagery over the past 24 hours. Solar wind: Over the past hours the solar wind parameters as measured by ACE reflected a waning influence of the previously ongoing mild high-speed stream from a negative polarity coronal hole. The total interplanetary magnetic field (B) reached a maximum of 8.1 nT with a minimum north-south component, Bz, of -5.2 nT. The solar wind speed varied between 337 km/s and 544 km/s. The B field phi angle was entirely in the negative sector (directed towards the Sun). The solar wind conditions are expected to register mostly nominal slow solar wind conditions over the next 24 hours. Some enhancements are possible later on Aug 04 and Aug 05 with an anticipated new mild high speed stream arrival. Geomagnetism: The geomagnetic conditions over the past 24 hours were quiet to unsettled. Predominantly geomagnetic conditions are expected for the next 24 hours with chances for isolated active periods later on Aug 04 and Aug 05, pending a possible new mild high speed stream arrival. Proton flux levels: Over the past 24 hours the greater than 10 MeV GOES proton flux has been at nominal levels and is expected to remain so over the next days with possible enhancements in case of any strong activity from SIDC Sunspot Groups 585 and 588. Electron fluxes at GEO: The greater than 2 MeV electron flux as measured by GOES 18 has briefly exceeded the 1000 pfu threshold over the past 24 hours, while the greater than 2 MeV electron flux as measured by GOES 19 has remained under the 1000 pfu threshold. Both electron fluxed are expected to remain mostly below the 1000 pfu threshold over the next days. The 24-hour electron fluence was at nominal levels and is expected to remain so in the next days. TODAY'S ESTIMATED ISN : 139, BASED ON 20 STATIONS. SOLAR INDICES FOR 02 Aug 2025 WOLF NUMBER CATANIA : /// 10CM SOLAR FLUX : 146 AK CHAMBON LA FORET : 014 AK WINGST : 011 ESTIMATED AP : 011 ESTIMATED ISN : 137, BASED ON 21 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 # #--------------------------------------------------------------------#