Viewing archive of Thursday, 24 May 2018

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2018 May 24 1316 UTC

SIDC Forecast

Valid from 1230 UTC, 24 May 2018 until 26 May 2018
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
24 May 2018073004
25 May 2018072006
26 May 2018073007

Bulletin

Newly numbered Catania sunspot group 84 rotating around the East limb produced multiple B flares yesterday. The largest flare was a C2.0 flare peaking at 18:21 UT. NOAA Active Regions 2710 and 2711 were mostly inactive. 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 some probability for C-class flares. Solar wind parameters decreasing varitations indicate fainting influence of positive polarity extension of the northern polar coronal hole. Solar wind speed gradually decreased during the period till around 470 km/s after reaching maximum of 550 km/s at 17:00 UT yesterday. Total magnetic field magnitude declined from 6.5 to 2 nT, while Bz component is varying now between -1.7 and +1.7 nT. Geomagnetic conditions reached unsettled levels (K= 3) during 06 - 15 UT yesterday, then both local index (Dourbes) and planetary (NOAA) returned to quiet levels. Mainly quiet geomgnetic conditions can be expected from now.

Today's estimated international sunspot number (ISN): 035, based on 22 stations.

Solar indices for 23 May 2018

Wolf number Catania031
10cm solar flux073
AK Chambon La Forêt012
AK Wingst010
Estimated Ap012
Estimated international sunspot number027 - Based on 27 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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