Viewing archive of Tuesday, 19 May 2026

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2026 May 19 1231 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

	10cm flux	Ap
19 May 2026	104	011
20 May 2026	101	010
21 May 2026	098	006

Solar Active Regions and flaring

Solar flaring activity was low over the past 24 hours, with only two C-class flares identified. Both were emitted by SIDC Sunspot Group 825 (NOAA Active Region 4436, Alpha magnetic configuration), with the brightest being SIDC flare 7732 (a C2 that peaked on 19 May at 07:40 UTC). More C-class flaring activity is likely in the next 24 hours.

Coronal mass ejections

No Earth-directed Coronal Mass Ejections (CME) were observed in the last 24 hours.

Solar wind

The Solar Wind (SW) conditions around Earth were affected by a glancing blow from a Coronal Mass Ejection (SIDC CME 656) that arrived on 19 May at 06:00 UTC as expected. The SW speed increased from 480 to 650 km/s, the interplanetary magnetic field (B) reached a maximum value of 8 nT, and its North-South component (Bz) varied from -7 to 5 nT. The effects from the glancing blow are expected to subside in the next 24 hours, with the exception of the SW speed that is predicted to have a more gradual decrease.

Geomagnetism

The geomagnetic conditions of the past 24 hours were affected by the arrival of a glancing blow from SIDC CME 656. The global conditions were increased from quiet to active levels (NOAA Kp 2- to 4-) while locally the effect was milder (K BEL 3, only on 19 May at 06:00-09:00 UTC). In the next 24 hours it is expected that the conditions will remain at a similar level.

Proton flux levels

The greater than 10 MeV proton flux, as measured by the GOES-19 satellite, was at nominal levels over the past 24 hours and is likely to remain so in the next 24 hours.

Electron fluxes at geostationary orbit

The greater than 2 MeV electron flux as, measured by GOES 19, was above the 1000 pfu alert threshold for most of the past 24 hours. It reached a peak value of 5200 pfu on 18 May at 13:10 UTC. It is expected to remain near the alert threshold in the next 24 hours. The electron fluence was at moderate levels in the past 24 hours and it is expected to remain at those levels in the next 24 hours.

Today's estimated international sunspot number (ISN): 073, based on 18 stations.

Solar indices for 18 May 2026

Wolf number Catania	097
10cm solar flux	105
AK Chambon La Forêt	014
AK Wingst	013
Estimated Ap	011
Estimated international sunspot number	087 - Based on 27 stations

Noticeable events summary

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

All times in UTC

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