Viewing archive of Friday, 10 October 2025

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2025 Oct 10 1231 UTC

SIDC Forecast

Solar flares

C-class flares expected, (probability >=50%)

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

	10cm flux	Ap
10 Oct 2025	120	010
11 Oct 2025	118	019
12 Oct 2025	115	014

Solar Active Regions and flaring

Solar flaring activity was moderate over the past 24 hours, with an M2 flare identified (SIDC flare 5702) on 9 Oct at 12:31 UTC. This is a peculiar event as it is associated with the SIDC Sunspot Group 657 (NOAA Active Region [AR] 4236) that rotated behind the solar limb on 8 Oct. Hence, it is estimated that this is a much brighter emission and partially obscured. The Earth-facing AR produced three C-class flares, two from SIDC Sunspot Group 661 (NOAA AR 4241, Beta magnetic configuration) and one from SIDC Sunspot Group 667 (NOAA AR 4249, Beta magnetic configuration). Solar flaring activity is expected to be low over the next 24 hours, featuring only a small number of relatively faint C-class flares.

Coronal mass ejections

No Earth-directed Coronal Mass Ejections (CME) were observed in the last 24 hours.

Solar wind

During the past 24 hours the Solar Wind (SW) conditions were gradually returning to a slow SW regime. The SW speed ranged from 270 to 410 km/s, while the interplanetary magnetic field (B) varied between 4 and 13 nT, and its North-South component (Bz) fluctuated between -6 and 11 nT. In the next 24 hours there is a change that a High Speed Stream (HSS) associated with SIDC Coronal Hole 116 and a glancing blow from SIDC Coronal Mass Ejection 578 will arrive. If the none of these arrivals materialises, the SW conditions are expected to feature a slow SW regime.

Geomagnetism

During the last 24 hours geomagnetic conditions were globally quiet to active (NOAA Kp 1- to 4-) and locally quiet to unsettled (K BEL 2 to 3). In the next 24 hours there is a change that a High Speed Stream (HSS) associated with SIDC Coronal Hole 116 and a glancing blow from SIDC Coronal Mass Ejection 578 will arrive. If both of these arrivals materialise, the geomagnetic conditions are expected to reach active to minor storm levels.

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 geostationary orbit

The greater than 2 MeV electron flux as measured by GOES 19 was above the 1000 pfu alert threshold on 9 Oct between 13:50 and 22:15 UTC, with a peak value at 5000 pfu. For the rest of the past 24 hours the flux was below but close to the alert threshold. In the next 24 hours it is expected to remain close to the 1000 pfu alert threshold. The 24-hour electron fluence was at moderate levels during the past 24 hours. It is expected to marginally drop and remain at moderate levels in the next 24 hours.

Today's estimated international sunspot number (ISN): 078, based on 13 stations.

Solar indices for 09 Oct 2025

Wolf number Catania	042
10cm solar flux	122
AK Chambon La Forêt	014
AK Wingst	006
Estimated Ap	005
Estimated international sunspot number	061 - Based on 18 stations

Noticeable events summary

Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive

All times in UTC

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