Viewing archive of Tuesday, 18 September 2018

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2018 Sep 18 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 18 Sep 2018 until 20 Sep 2018
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
18 Sep 2018068010
19 Sep 2018067005
20 Sep 2018067005

Bulletin

The visible side of the Sun is presently spotless and consequently there was no flaring activity reported during last 24 hours. We expect such a low flaring activity to persist in the coming hours. No Earth directed CMEs were observed, and the solar protons remained at the background level.

The solar wind speed is slowly decreasing and it presently amounts about 480 km/s. The interplanetary magnetic field magnitude is about 4 nT. The low latitudinal extension of the northern polar coronal hole has reached the central meridian this morning. The possible arrival of the associated fast solar wind might be expected at the Earth late on September 21 or in the morning of September 22. During last 24 hours the geomagnetic conditions were quiet to unsettled and we expect them to stay so in the coming hours.

Today's estimated international sunspot number (ISN): 000, based on 27 stations.

Solar indices for 17 Sep 2018

Wolf number Catania013
10cm solar flux068
AK Chambon La Forêt017
AK Wingst015
Estimated Ap014
Estimated international sunspot number013 - Based on 22 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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