Viewing archive of Monday, 17 May 2021

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2021 May 17 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 17 May 2021 until 19 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
17 May 2021073007
18 May 2021075011
19 May 2021077018

Bulletin

Solar activity was very low over the past 24 hours with no noticeable flare activity. There is only one visible active region on the disk (NOAA AR 2822, Catania 93, with alpha magnetic field configuration). A new AR is rotating into view, which may increase solar activity in the next 24 hours.

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.

The solar wind speed at the Earth in the last 24 hours has been around 410 km/s, with interplanetary magnetic field around 6 nT. The interplanetary magnetic field polarity was negative (towards the Sun). Similar conditions (slow solar wind) are expected for the next 24 hours. The high speed solar wind from the coronal hole that crossed central meridian on 15 May is expected to arrive to the Earth in about 48 hours.

Geomagnetic conditions were mostly quiet both at planetary and local levels (Kp 1-2 and K Dourbes: 1-3). The CME from 13 May could arrive to the Earth within 24 hours and cause active geomagnetic conditions (although it will probably pass north of the Earth).

Today's estimated international sunspot number (ISN): 011, based on 17 stations.

Solar indices for 16 May 2021

Wolf number Catania///
10cm solar flux073
AK Chambon La Forêt008
AK Wingst004
Estimated Ap003
Estimated international sunspot number011 - Based on 21 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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