Viewing archive of Tuesday, 12 May 2026

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2026 May 12 1231 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

Active conditions expected (A>=20 or K=4)

Solar protons

Quiet

	10cm flux	Ap
12 May 2026	114	007
13 May 2026	112	032
14 May 2026	111	012

Solar Active Regions and flaring

Solar flaring activity was low over the past 24 hours, with only C-class flares. The strongest flare was a C1.8 flare (SIDC Flare 7676), peaking at 14:15 UTC on May 11, which was associated with SIDC Sunspot Group 860 (NOAA Active Region 4432, magnetic type beta-gamma). There are currently four numbered active regions on the solar disk. SIDC Sunspot Group 860 (NOAA Active Region 4432) is the most complex group. SIDC Sunspot Group 856 (NOAA Active Region 4431) has rotated over the west limb. The solar flaring activity is expected to be moderate over the next 24 hours, with M-class flares likely and a small chance for X-class flares.

Coronal mass ejections

A narrow and slow Coronal Mass Ejection (SIDC CME 651) was observed in LASCO/C2 and C3 coronagraph imagery starting from around 22:00 UTC on May 11. The CME is likely associated with an eruption from SIDC Sunspot Group 825 (NOAA Active Region 4436), located in the northeast quadrant. While the bulk of the ejecta is expected to miss Earth, a glancing blow early on May 14 cannot be fully excluded. No other Earth- directed CMEs were observed in the available coronagraph imagery.

Solar wind

Over the past 24 hours, the solar wind parameters (ACE) reflected mostly slow solar wind conditions. Speed values ranged between 350 km/s and 410 km/s. The interplanetary magnetic field values were between 5 nT and 8 nT. The Bz component varied between -6 nT and 7 nT. The interplanetary magnetic field angle was mostly in the positive sector. Enhanced solar wind conditions may be possible over the next 24 hours due to the possible arrival of a glancing blow associated with the Coronal Mass Ejection (SIDC CME 650) observed at 13:48 UTC on May 10, together with a possible high-speed stream influence from the mid-latitude positive polarity coronal hole (SIDC Coronal Hole 159).

Geomagnetism

Geomagnetic conditions globally and locally were mostly at quiet levels (NOAA Kp 1 to 2, K BEL 1 to 2). Active to minor storm conditions may be possible over the next 24 hours, due to the possible arrival of a glancing blow associated with the Coronal Mass Ejection (SIDC CME 650) observed at 13:48 UTC on May 10, together with a possible high- speed stream influence from the mid-latitude positive polarity coronal hole (SIDC Coronal Hole 159).

Proton flux levels

The greater than 10 MeV proton flux was below the 10 pfu 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 GOES 19 was below the 1000 pfu threshold in the last 24 hours. The greater than 2 MeV electron flux is expected to be below the 1000 pfu threshold over the next 24 hours. The 24-hour electron fluence is presently at normal levels and is expected to remain so over the next 24 hours.

Today's estimated international sunspot number (ISN): 058, based on 19 stations.

Solar indices for 11 May 2026

Wolf number Catania	073
10cm solar flux	///
AK Chambon La Forêt	010
AK Wingst	006
Estimated Ap	006
Estimated international sunspot number	083 - Based on 20 stations

Noticeable events summary

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

All times in UTC

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