Viewing archive of Wednesday, 19 May 2021

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2021 May 19 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 19 May 2021 until 21 May 2021
Solar flares

Quiet conditions (<50% probability of C-class flares)

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
19 May 2021077016
20 May 2021079007
21 May 2021079007

Bulletin

Two active regions (ARs) visible on the disk, NOAA AR 2822 (alpha magnetic field configuration) and AR 2824 (beta magnetic field configuration). Only B-class flares in past 24 hours. C-class flares are possible.

No Earth-directed Coronal Mass Ejections (CMEs) have been detected in the available coronagraphic imagery in the last 24 hours.

The greater than 10 MeV proton flux was at nominal levels over the past 24 hours and is expected to remain so for the next 24 hours. The greater than 2 MeV electron flux remained below the 1000 pfu in the past 24 hours and is expected to remain so. The 24-hour electron fluence was at normal levels in the past 24 hours and is expected to remain so.

In the last 24 hours, the solar wind speed varied between 350 and 400 km/s. The interplanetary magnetic field reached 9 nT with Bz mostly positive. The interplanetary magnetic field polarity was negative (towards the Sun). The high speed solar wind from the coronal hole that crossed the central meridian on 15 May is expected to arrive to the Earth today.

Geomagnetic conditions have been mostly quiet (KDourbes 0-3, Kp 1-2). Active conditions can be expected when the high speed solar wind stream arrives to the Earth today.

Today's estimated international sunspot number (ISN): 026, based on 23 stations.

Solar indices for 18 May 2021

Wolf number Catania///
10cm solar flux076
AK Chambon La Forêt010
AK Wingst012
Estimated Ap012
Estimated international sunspot number028 - Based on 32 stations

Noticeable events summary

DayBeginMaxEndLocStrengthOP10cmCatania/NOAARadio burst types
None

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

All times in UTC

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