Viewing archive of Monday, 21 May 2018

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2018 May 21 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 21 May 2018 until 23 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
21 May 2018069005
22 May 2018070007
23 May 2018071010

Bulletin

Solar activity was at very low levels. A new sunspot region has rounded the east limb (Catania 82), but it is small and -so far- 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 very low levels. The solar wind speed at L1 is below 400 km/s with interplanetary magnetic field magnitude of 5 nT (recorded by ACE). Geomagnetic conditions have been quiet and are expected to remain so. On May 23, the high speed solar wind from the positive polarity extension of the northern polar coronal hole may arrive to the Earth and cause disturbed geomagnetic conditions (although it might pass north of the Earth without affecting it).

Today's estimated international sunspot number (ISN): 011, based on 23 stations.

Solar indices for 20 May 2018

Wolf number Catania///
10cm solar flux069
AK Chambon La Forêt///
AK Wingst003
Estimated Ap003
Estimated international sunspot number000 - Based on 30 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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