Viewing archive of Monday, 22 May 2023

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2023 May 22 1254 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
22 May 2023	163	018
23 May 2023	163	028
24 May 2023	163	016

Solar Active Regions and flaring

Solar flaring activity was at moderate levels in the past 24 hours. The strongest activity was an M2.6-flare with start time 15:49 UTC, peak time 16:04 UTC, end time 16:31 UTC on May 21st. The flaring was produced by NOAA AR 3311 (beta-gamma-delta), which is currently the largest, most active and most complex sunspot group on the visible solar disc. Multiple low to high C-class flaring was produced by NOAA AR 3305 (beta) from the west limb. The remaining six active regions have been relatively simple and inactive. The solar flaring activity is expected to be at low to moderate levels over the next 24 hours with some chances for isolated X-class flaring from NOAA AR 3311.

Coronal mass ejections

A fast full halo coronal mass ejection (CME) was first observed in the LASCO/C2 chronograph imagery at 00:12 UTC on May 22nd. The CME is back-sided and is not expected to impact Earth. No Earth- directed CMEs have been detected in the available coronagraph imagery.

Coronal holes

A negative polarity equatorial coronal hole has crossed the central meridian on May 21st. An associated high speed stream is expected to arrive at Earth as early as May 23rd.

Solar wind

Over the past 24 hours the solar wind parameters (ACE and DSCOVR) Solar wind parameters were under the mixed influence of a high speed stream (HSS) arrival from a negative polarity coronal hole and a weak ICME arrival related to the flare-driven CME from May 17th. The solar wind velocity decreased varied between 439 and 657 km/s. The interplanetary magnetic field reached a maximum value of 13.22 nT and a minimum Bz of -10.57 nT. The B field was switching orientation between the positive and the negative sector (directed away from and towards the Sun). The solar wind conditions are expected to remain elevated over the next 24 hours with the ongoing ICME passage with possible further enhancements on May 23rd with the expected HSS arrival.

Geomagnetism

The geomagnetic conditions over the past 24 hours have reached globally moderate storm levels between 18:00 and 24:00 UTC on May 21st. Locally over Belgium mostly active conditions were registered with an isolated minor storm period between 18:00 and 19:00 UTC on May 21st. Mostly unsettled to active geomagnetic conditions are expected over the next 24 hours with chances for minor to moderate storm intervals due to the expected high speed stream arrival on May 23rd.

Proton flux levels

Over the past 24 hours the greater than 10 MeV GOES proton flux was at nominal levels and is expected to remain so over the next days depending on flaring and possible CMEs activity, particularly from NOAA AR 3311.

Electron fluxes at geostationary orbit

The greater than 2 MeV electron flux has reached the 1000 pfu threshold between 15:00 and 16:00 UTC on May 21st and returned to background values thereafter. The greater than 2 MeV electron flux is expected to be below the 1000 pfu threshold in the upcoming days. The 24h electron fluence was at nominal levels and is expected to remain so over the next days.

Today's estimated international sunspot number (ISN): 136, based on 15 stations.

Solar indices for 21 May 2023

Wolf number Catania	///
10cm solar flux	163
AK Chambon La Forêt	045
AK Wingst	024
Estimated Ap	024
Estimated international sunspot number	138 - 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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