Viewing archive of Monday, 23 October 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Oct 23 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 23 Oct 2017 until 25 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
23 Oct 2017077009
24 Oct 2017079037
25 Oct 2017080046

Bulletin

Solar activity was very low with only a single B2.2 flare peaking at 12:41 UT from a new region rotating around the East limb in the Northern hemisphere. The region is now numbered Catania group 61 or NOAA region 2686. Although there is a chance for C flares and even a slight chance for an M flare from both regions on disk, the general outlook is that flaring will 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 declined slightly from around 430 km/s to around 380 km/s. Total magnetic field was below 6nT with Bz variable and not below -4nT. The magnetic field phi angle indicated connection to a negative sector. Solar wind is expected to see transition into a positive polarity sector later today and which is then followed by the influence of the high speed stream from the equatorial extension of the northern polar positive polarity coronal hole that started transiting the central meridian around noon October 20. Geomagnetic conditions were quiet to unsettled (both local K Dourbes and NOAA Kp 1-3). Geomagnetic conditions are expected to increase under the influence of the upcoming high speed stream. Associated geomagnetic activity is expected to remain limited to possible periods of minor geomagnetic storming over the next days.

Today's estimated international sunspot number (ISN): 023, based on 14 stations.

Solar indices for 22 Oct 2017

Wolf number Catania///
10cm solar flux077
AK Chambon La Forêt009
AK Wingst006
Estimated Ap006
Estimated international sunspot number012 - 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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