:Issued: 2026 Jul 17 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 60717 SIDC SOLAR BULLETIN 17 Jul 2026, 1230UT SIDC FORECAST SOLAR FLARES : C-class flares expected, (probability >=50%) GEOMAGNETISM : Active conditions expected (A>=20 or K=4) SOLAR PROTONS : Quiet PREDICTIONS FOR 17 Jul 2026 10CM FLUX: 099 / AP: 008 PREDICTIONS FOR 18 Jul 2026 10CM FLUX: 100 / AP: 015 PREDICTIONS FOR 19 Jul 2026 10CM FLUX: 100 / AP: 008 Solar Active Regions and flaring: Solar flaring activity has been low over the past 24 hours, with very few C-class flares. The strongest flare was a C5.2 flare (SIDC Flare 8206) from beyond the east limb, peaking at 21:35 UTC on July 16. There are currently four numbered active regions on the solar disk. The most complex ones have a beta magnetic configuration. SIDC Sunspot Group 910 is currently rotating across the west limb. The 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: A wide Coronal Mass Ejection (SIDC CME 690) was observed in LASCO/C2 coronagraph imagery, lifting off from the east limb, starting from 00:10 UTC on July 17. It is most likely associated with a C1.5 flare (SIDC flare 8207, peaking at 00:02 UTC) from beyond the east limb. It is not expected to impact Earth. No other Earth-directed CMEs were observed in the available coronagraph imagery during the last 24 hours. Solar wind: Over the past 24 hours, the solar wind parameters (SOLAR-1 and ACE) showed a gradual return to slow solar wind conditions. The solar wind speed decreased from 470 km/s to 370 km/s. The interplanetary magnetic field was between 3 nT and 6 nT. The Bz component was between -5 nT and 3 nT. The interplanetary magnetic field angle phi was predominantly in the positive sector. Slow solar wind conditions are expected initially over the next 24 hours, possibly followed by enhanced conditions due to the expected arrival of a mild high-speed stream from the northern, positive polarity coronal hole (SIDC Coronal Hole 174). Geomagnetism: Geomagnetic conditions globally were quiet (NOAA Kp 1 to 2) during the past 24 hours. Geomagnetic conditions locally during the past 24 hours were initially unsettled (K Bel 3), reaching active levels (K Bel 4) between 14:00 UTC and 15:00 UTC on July 16. A decrease to mostly quiet levels (K Bel 1 to 2) followed. Mostly quiet to unsettled conditions (NOAA Kp 1 to 3) are expected over the next 24 hours, with a chance of isolated active intervals (NOAA Kp 4) due to the expected arrival of a mild high- speed stream from the northern, positive polarity coronal hole (SIDC Coronal Hole 174). Proton flux levels: The greater than 10 MeV proton flux was below the 10 pfu threshold during the past 24 hours. It is expected to remain below the threshold level over the next 24 hours. Electron fluxes at GEO: The greater than 2 MeV electron flux measured by GOES 18 was above the 1000 pfu threshold between 17:45 UTC and 23:45 UTC on July 16. The greater than 2 MeV electron flux is expected to remain mostly below the 1000 pfu threshold over the next 24 hours. The 24-hour electron fluence was at normal levels and it is expected to remain so over the next 24 hours. TODAY'S ESTIMATED ISN : 035, BASED ON 22 STATIONS. SOLAR INDICES FOR 16 Jul 2026 WOLF NUMBER CATANIA : 060 10CM SOLAR FLUX : 101 AK CHAMBON LA FORET : 012 AK WINGST : 012 ESTIMATED AP : 011 ESTIMATED ISN : 052, BASED ON 23 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 # #--------------------------------------------------------------------#