Viewing archive of Friday, 29 August 2025

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2025 Aug 29 1231 UTC

SIDC Forecast

Solar flares

M-class flares expected (probability >=50%)

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

	10cm flux	Ap
29 Aug 2025	232	007
30 Aug 2025	234	007
31 Aug 2025	234	007

Solar Active Regions and flaring

A total of 16 numbered sunspot groups were identified on the disk over the past 24 hours. Solar flaring activity was high over the past 24 hours, with 5 M-class flares identified. The largest flare was a M1.5 flare (SIDC Flare 5260) peaking on August 28 at 20:40 UTC, which was produced by SIDC Sunspot Group 621 (NOAA Active Region 4203). Solar flaring activity is expected to be moderate over the next 24 hours, with M-class flares likely.

Coronal mass ejections

No Earth-directed Coronal Mass Ejections (CMEs) have been observed in the last 24 hours.

Coronal holes

A narrow equatorial negative polarity coronal hole crossed central meridian on 28 August, its associated high speed stream may be expected at the Earth on 1 September.

Solar wind

The Earth is inside slow solar wind with speeds around 400 km/s and interplanetary magnetic fields of about 7 nT (directed towards the Sun, negative polarity). Similar conditions can be expected for the coming 24 hours.

Geomagnetism

Geomagnetic conditions have been quiet to unsettled (Kp between 0 and 3 and K_Bel 0 and 2). Similar conditions are expected for the next 24 hours.

Proton flux levels

The greater than 10 MeV proton flux has been below the 10 pfu threshold. It is expected to remain at nominal levels.

Electron fluxes at geostationary orbit

The greater than 2 MeV electron flux as measured by GOES 18 and 19 remained below the 1000 pfu alert threshold, similar conditions expected for the next 24 hours. The 24 h electron fluence was at normal levels and is expected to remain so.

Today's estimated international sunspot number (ISN): 211, based on 17 stations.

Solar indices for 28 Aug 2025

Wolf number Catania	204
10cm solar flux	232
AK Chambon La Forêt	013
AK Wingst	007
Estimated Ap	008
Estimated international sunspot number	201 - Based on 15 stations

Noticeable events summary

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

All times in UTC

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