Viewing archive of Wednesday, 29 October 2025

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2025 Oct 29 1233 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

Minor storm expected (A>=30 or K=5)

Solar protons

Quiet

	10cm flux	Ap
29 Oct 2025	122	035
30 Oct 2025	122	019
31 Oct 2025	122	007

Solar Active Regions and flaring

Solar flaring activity was low over the past 24 hours, with only minor C-class flares identified. A total of 7 numbered sunspot groups were identified on the disk over the past 24 hours. The largest flare was a C1.6 flare (SIDC Flare 5882) peaking on October 28 at 16:26 UTC, which was produced by SIDC Sunspot Group 653 (NOAA Active Regions 4232, 4267). Solar flaring activity is expected to be low over the next 24 hours, with C-class flares likely.

Coronal mass ejections

On 28 October at 15:21 UT, a CME (SIDC CME 589) erupted towrads the east, with an angular width of around 70 degreess and speed around 400 km/s. Associated dimmings were observed in relation the this CME at 50 degrees eastern longitude, close to the equator. We may observe a glancing blow of this CME at the Earth on 1 November, with a low geomagnetic impact.

A partial halo CME (angular width around 140 degrees) was first seen by LASCO C2 at 00:48 UT on 29 October. This CME is backsided and not expected to arrive to the Earth.

Coronal holes

SIDC Coronal Hole 123 (mid-latitude coronal hole with a positive polarity) crossed the central meridian on October 25. A small coronal hole (SIDC Coronal Hole 128) crossed central meridian on 27 October, it is an equatorial coronal hole with positive polarity.

Solar wind

Over the past 24 hours, solar wind parameters (ACE and DSCOVR) reflected the arrival of the expected high speed stream from SIDC Coronal Hole 123. The speed has so far been lower than expected, and it is now around 550 km/s with interplanetary magnetic field around 10 nT. We expect speeds to increase further in the coming 24 hours.

Geomagnetism

Geomagnetic conditions reached minor storm conditions locally (K-Bel up to 5 and Kp up to 4.33). In the next 24 hours, we can expect up to minor storm conditions, with possible moderate storm periods.

Proton flux levels

The greater than 10 MeV GOES proton flux was below the 10 pfu threshold level over the past 24 hours and is expected to remain so for the next 24 hours.

Electron fluxes at geostationary orbit

The greater than 2 MeV electron flux measured by GOES 18 and GOES 19 was below the 1000 pfu threshold. The greater than 2 MeV electron flux is expected to remain below the 1000 pfu threshold over the next 24 hours. The 24-hour electron fluence was at normal levels and is expected to be at normal levels over the next 24 hours.

Today's estimated international sunspot number (ISN): 097, based on 09 stations.

Solar indices for 28 Oct 2025

Wolf number Catania	116
10cm solar flux	122
AK Chambon La Forêt	028
AK Wingst	024
Estimated Ap	023
Estimated international sunspot number	108 - Based on 19 stations

Noticeable events summary

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

All times in UTC

<< Go to daily overview page