Viewing archive of Friday, 31 May 2024

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2024 May 31 1236 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

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

Solar protons

Quiet

	10cm flux	Ap
31 May 2024	179	007
01 Jun 2024	183	025
02 Jun 2024	188	010

Solar Active Regions and flaring

Solar activity was moderate over the last 24 hours. The largest flare of the period was an M1.0 flare with peak time 11:20 UTC May 31 from Catania sunspot group 28 (NOAA AR 3697). This region also produced a C9.8 flare with peak time 03:37 UTC May 31. Newly numbered Catania sunspot group 30 (NOAA AR 3698) emerged quickly in the north eastern quadrant and produced multiple C-class flares. Catania sunspot group 22 (NOAA AR 3691) decayed slightly and produced C-class flaring activity. The rest of the regions were either stable or in decay and were quiet. The solar flaring activity is expected to be moderate over the next 24 hours with C-class flares expected, M-class flares likely and a chance for X-class flares.

Coronal mass ejections

No Earth directed Coronal Mass Ejections (CMEs) have been detected in the available coronagraph imagery.

Solar wind

The solar wind conditions were mildly enhanced. The interplanetary magnetic showed signs of a weak magnetic structure, with values up to 10 nT and sustained periods of negative Bz with a minimum value of -8nT. The solar wind speed was slow with value between 350 and 375 km/s. Generally slow solar wind conditions are expected on May 31 with some continued enhancements in the magnetic field possible. A glancing blow from the partial halo CME on May 29 and the weak influence from the small positive polarity coronal hole which crossed the central meridian on May 29 may cause higher solar wind speeds and magnetic field values from June 01.

Geomagnetism

Geomagnetic conditions were mostly at quiet to active levels, with an isolated interval of minor geomagnetic storms 03:00 – 06:00 UTC (NOAA Kp 5- and Local K Bel 4). Geomagnetic conditions are expected to be mostly at unsettled to active levels on May 31. Minor storm conditions may be possible from June 01, due to the anticipated glancing blow from the May 29 CME.

Proton flux levels

Over the past 24 hours the greater than 10 MeV GOES proton flux was below the 10pfu threshold and is expected to remain so for the next day. There is a slight chance that the proton flux may increase due to strong flaring from NOAA AR 3697, but this is unlikely due to its current position.

Electron fluxes at geostationary orbit

The greater than 2 MeV electron flux remained below the 1000 pfu threshold as measured by GOES 16. It is expected to remain below this threshold over the next days. The 24-hour electron fluence was at nominal levels. The electron fluence is expected remain at nominal levels over the next days.

Today's estimated international sunspot number (ISN): 144, based on 13 stations.

Solar indices for 30 May 2024

Wolf number Catania	///
10cm solar flux	175
AK Chambon La Forêt	021
AK Wingst	014
Estimated Ap	012
Estimated international sunspot number	141 - Based on 19 stations

Noticeable events summary

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

All times in UTC

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