Solar Activity Alerts

:Product: Forecast Discussion :Issued: 2026 Oct 24 1230 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # Solar Activity .24 hr Summary... Solar activity continued at low levels with the largest flare being a C1.3 at 23/1907 UTC from the only active region with sunspots on disk: Region 4560 (N13W65, Eao/beta-gamma). Decay continued to be observed in its intermediate spots over the past 24 hours. No new Earth-directed CMEs were observed in available coronagraph imagery. .Forecast... Solar activity is expected to remain at low levels through 26 Oct, with a slight chance for isolated M-class flares (R1-R2, Minor-Moderate). Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux reached high levels in the past 24h, with max flux of 3,169 pfu at 23/1540 UTC. The greater than 10 MeV proton flux remained steady at background levels. .Forecast... The greater than 2 MeV electron flux is expected to continue reaching high levels through 26 Oct. The greater than 10 MeV proton flux is anticipated to persist at background levels through 26 Oct. Solar Wind .24 hr Summary... Solar wind parameters reflected diminishing positive polarity CH HSS influences. Total magnetic field strength (Bt) was about 5 nT with the Bz component mostly negative, briefly observed as far south as -6 nT around 23/1740 UTC. Solar wind speeds maintained between ~400-450 km/s. Phi angle was predominantly in the positive solar sector (away from the Sun). .Forecast... Solar wind conditions are expected to continue at similar levels over 24 Oct. Enhanced solar wind conditions are likely on 25-26 Oct due to combined influences of a negative polarity CH HSS and possible glancing CME effects from the 21 Oct eruptions. Geospace .24 hr Summary... Geomagnetic activity was mostly quiet during the period, reaching active levels during an isolated synoptic period (23/1800-2100 UTC) due to a sustained Bz negative period. .Forecast... Quiet to unsettled conditions are expected on 24 Oct as CH HSS influences wane. Periods of active conditions, with a chance for G1 (Minor) storming, are anticipated on 25-26 Oct due to combined effects from a negative polarity coronal hole and potential glancing CME impacts.

Space Weather Message Code: ALTEF3 Serial Number: 3756 Issue Time: 2026 Oct 24 0904 UTC CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1,000pfu Continuation of Serial Number: 3755 Begin Time: 2026 Oct 23 1140 UTC Yesterday Maximum 2MeV Flux: 3169 pfu Max time: 2026 Oct 23 1540 UTC

:Product: Forecast Discussion :Issued: 2026 Oct 24 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # Solar Activity .24 hr Summary... Solar activity continued at low levels. The largest flare was a C3.3/Sf at 23/0542 UTC from Region 4560 (N13W58, Eai/beta-gamma). Decay was observed in the intermediate spots of AR4560 over the past 24 hours. The other active region on the visible solar disk, Region 4557 (N07W75, Cao/beta), was responsible for a few low-level C-class flares. No new Earth-directed CMEs were observed in available coronagraph imagery. .Forecast... Solar activity is expected to remain at low levels through 26 Oct, with a slight chance for isolated M-class flares (R1-R2, Minor-Moderate), mostly due to the flare potential of Region 4560. Energetic Particle .24 hr Summary... The greater than 2 MeV electron flux reached high levels. The greater than 10 MeV proton flux remained steady at background levels. .Forecast... The greater than 2 MeV electron flux is expected to continue reaching high levels on 24-26 Oct. The greater than 10 MeV proton flux is anticipated to persist at background levels through 26 Oct. Solar Wind .24 hr Summary... Solar wind parameters reflected continued positive polarity CH HSS influences. Total magnetic field strength (Bt) was at or below 6 nT and the Bz component was briefly observed as far south as -6 nT. Solar wind speeds maintained between ~400-450 km/s. Phi angle was predominantly in the positive solar sector (away from the Sun). .Forecast... Solar wind conditions are expected to continue at similar levels over 24 Oct. Enhanced solar wind conditions are likely on 25-26 Oct due to combined influences of a negative polarity CH HSS and possible glancing CME effects from the 21 Oct eruptions. Geospace .24 hr Summary... Geomagnetic activity reached active levels. .Forecast... Active conditions are expected on 24 Oct as CH HSS influences wane. Additional periods of active conditions, with a chance for G1 (Minor) storming, are anticipated on 25-26 Oct due to combined effects from a recently emerged negative polarity coronal hole and potential glancing CME impacts.