Viewing archive of Saturday, 17 October 2015

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2015 Oct 17 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 17 Oct 2015 until 19 Oct 2015
Solar flares

M-class flares expected (probability >=50%)

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
17 Oct 2015113016
18 Oct 2015117015
19 Oct 2015120009

Bulletin

Nine low-level C-class flares were recorded, the strongest a C4.3 flare from NOAA 2435 peaking at 13:24UT. There may still be an active region at the southeast limb trailing NOAA 2435. NOAA 2434 lost its small delta southeast of the main spot, but developed another one to the north. NOAA 2436 shows some magnetic complexity in its trailing portion. No earth- directed coronal mass ejections have been observed.

There's a chance on an M-class flare from any of the active regions NOAA 2434, 2435, or 2436.

Solar wind speed declined from 400 km/s to 350 km/s, with no sign of a high speed stream (HSS) from the trans-equatorial coronal hole (CH). Bz ranged between -5 and +7 nT. The interplanetary magnetic field (IMF) was mostly directed towards the Sun (negative). Quiet to unsettled geomagnetic conditions were observed. An equatorial CH will start transiting the central meridian later today and its HSS may affect the geomagnetic environment late on 20 or on 21 October.

Mostly quiet to unsettled geomagnetic conditions are expected, with a chance on an active episode.

Today's estimated international sunspot number (ISN): 072, based on 05 stations.

Solar indices for 16 Oct 2015

Wolf number Catania///
10cm solar flux109
AK Chambon La Forêt010
AK Wingst007
Estimated Ap007
Estimated international sunspot number051 - Based on 15 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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