Viewing archive of Thursday, 26 October 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Oct 26 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 26 Oct 2017 until 28 Oct 2017
Solar flares

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

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
26 Oct 2017079021
27 Oct 2017079017
28 Oct 2017079011

Bulletin

Quiet solar conditions were reported with the X-ray flux seeing only a low B2 class flare peaking at 23:59UT from Catania group 61 (NOAA region 2686). Both active regions on disk are relatively simple (Mag.Type: Alpha) and small. Especially Catania group 60 (NOAA region 2685) shrunk in size. The X-ray flux is expected to remain below C level. Proton flux levels were at background values and are expected to remain so. No Earth directed CME's were recorded in coronagraph data.

Solar wind speed saw peaks of close to 650 km/s before starting a gradual decline towards values of near 560km/s presently. Total magnetic field was mainly in the 4-6.5 nT range with Bz variable but predominantly negative in the last 6 hours with values down to -6.3 nT. The present influence of the coronal hole high speed stream will gradually fade and speeds should decline over the next 24-48 hours. Geomagnetic conditions were quiet to active (local K Dourbes 1-4 and NOAA Kp 2-4). Geomagnetic conditions are expected to remain quiet to active for the next 24 hours and quiet to unsettled afterwards as the coronal hole high speed stream fades.

Today's estimated international sunspot number (ISN): 024, based on 16 stations.

Solar indices for 25 Oct 2017

Wolf number Catania023
10cm solar flux079
AK Chambon La Forêt030
AK Wingst023
Estimated Ap025
Estimated international sunspot number024 - Based on 20 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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