Viewing archive of Thursday, 18 April 2019

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2019 Apr 18 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 18 Apr 2019 until 20 Apr 2019
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
18 Apr 2019076001
19 Apr 2019075008
20 Apr 2019073006

Bulletin

Solar activity was at very low levels. The two currently visible sunspot groups are quiet. A small-sized coronal dimming (location: S45E10 at 21UT) was observed following a magnetic reconnection event during the afternoon of 17 April. No earth-directed coronal mass ejections were observed over the last 24 hours. The greater than 10 MeV proton flux was at nominal values.

Solar activity is expected to remain at very low levels.

Solar wind speed gradually decreased from 340 km/s to its current values near 300 km/s (DSCOVR). Bz varied between -4 and +4 nT, with a positive stretch from 20UT till 05UT. The interplanetary magnetic field was directed towards the Sun (negative sector). Quiet geomagnetic conditions were observed.

Quiet geomagnetic conditions are expected to continue, with a chance on an unsettled interval on 19-20 April due to anticipated effects from a sector boundary crossing and from a weak wind stream related to a diffuse extension of the positive polarity polar coronal hole.

Today's estimated international sunspot number (ISN): 027, based on 22 stations.

Solar indices for 17 Apr 2019

Wolf number Catania012
10cm solar flux076
AK Chambon La Forêt008
AK Wingst///
Estimated Ap006
Estimated international sunspot number015 - 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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