Viewing archive of Wednesday, 23 May 2018

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2018 May 23 1255 UTC

SIDC Forecast

Valid from 1230 UTC, 23 May 2018 until 25 May 2018
Solar flares

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

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
23 May 2018072015
24 May 2018073008
25 May 2018074007

Bulletin

Solar activity increased during the period due to a new region rotating around the East limb in the Northern hemisphere. This new region produced thirteen B-class flares among them the largest B8.9 flare peaking at 14:59 UT yesterday. No earth-directed coronal mass ejections (CMEs) were observed in available coronagraphic imagery. The greater than 10 MeV proton flux was at nominal levels. Solar activity is expected to be at low levels with a significant chance for C-class flare. Solar wind speed gradually increased as expected from around 320 km/s to around 490 km/s during the period under the influence of positive polarity extension of the northern polar coronal hole. Total magnetic field varied from 2 to 12 nT, while Bz component varied from +10 to -9 nT. Geomagnetic conditions were mostly quiet until 06:00 UT today, then both local index (Dourbes) and planetary (NOAA) reached the value K = 3 due to the enhanced solar wind speed. Mainly unsettled and active geomgnetic conditions can be expected today and tomorrow.

Today's estimated international sunspot number (ISN): 027, based on 14 stations.

Solar indices for 22 May 2018

Wolf number Catania013
10cm solar flux071
AK Chambon La Forêt013
AK Wingst007
Estimated Ap006
Estimated international sunspot number013 - 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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