Viewing archive of Tuesday, 29 April 2025

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2025 Apr 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 Apr 2025	154	011
30 Apr 2025	154	011
01 May 2025	154	007

Solar Active Regions and flaring

Solar flaring activity was moderate over the past 24 hours, with three M-class flares detected. A total of 10 sunspot groups were observed on the visible solar disk, indicating that we remain in a highly active phase of the solar cycle. The largest flare was an M1.7 event (SIDC Flare 4232), which peaked on April 29 at 05:13 UTC. It originated from SIDC Sunspot Group 486 (NOAA Active Region 4079), currently located at N07E77. This region has a Beta- Gamma magnetic configuration, showed signs of growth over the past 24 hours, and also produced several C-class flares. SIDC Sunspot Group 482 (NOAA Active Region 4070), currently positioned at S12W47, also has a Beta- Gamma configuration. It remained stable during the reporting period and did not produce any flaring activity. The returning SIDC Sunspot Group 455 (formerly NOAA Active Region 4043, now renumbered as 4078), currently located at N16W50, has a Beta magnetic configuration. This region showed signs of growth over the past 24 hours and produced the second- and third- largest flare of the period: an M1.6 flare (SIDC Flare 4238), which peaked on April 29 at 10:57 UTC, and an M1.3 flare (SIDC Flare 4237), which peaked on April 29 at 10:02 UTC. Solar flaring activity is expected to remain moderate over the next 24 hours, with C-class flares likely and a continued chance for M-class flares.

Coronal mass ejections

No Earth-directed CMEs were observed in the available coronagraph imagery in the last 24 hours.

Coronal holes

The recurrent SIDC Coronal Hole 99 (trans-equatorial elongated coronal hole with a negative polarity) reached the central meridian today, on April 29. (It first reached the central meridian on April 06)

Solar wind

The Earth remains under the influence of a slow solar wind, with speeds holding steady around 400 km/s. The total interplanetary magnetic field (IMF) gradually increased, reaching a peak of 9.5 nT around April 29 at 04:00 UTC, before returning to values near 6 nT. Slow solar wind conditions are expected to persist over the next 24 hours, with only a very small chance of seeing the arrival of a high-speed stream from the positive polarity coronal hole located in the southern hemisphere (SIDC Coronal Hole 104). Looking ahead, in approximately 3 to 4 days, the arrival of a high-speed stream associated with the SIDC Coronal Hole 99 (a large, elongated trans-equatorial coronal hole with negative polarity) which is crossing the central meridian today, on April 29.

Geomagnetism

Geomagnetic conditions have been quiet to unsettled globally and locally (Kp and K_Bel up to 3). The possible arrival of a high speed solar wind stream may increase conditions to active levels. Otherwise, mostly quiet conditions can be expected.

Proton flux levels

The greater than 10 MeV proton flux was below the threshold level over the past 24 hours. It is expected to remain below the threshold level over the next 24 hours.

Electron fluxes at geostationary orbit

The greater than 2 MeV electron flux measured by GOES 18 and 19has been above the threshold over the past 24 hours. The greater than 2 MeV electron flux may decrease over the next 24 hours.The 24-hour electron fluence is presently between normal and moderate levels, it may decrease over the next 24 hours.

Today's estimated international sunspot number (ISN): 109, based on 28 stations.

Solar indices for 28 Apr 2025

Wolf number Catania	126
10cm solar flux	154
AK Chambon La Forêt	005
AK Wingst	005
Estimated Ap	004
Estimated international sunspot number	115 - Based on 34 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