Viewing archive of Tuesday, 25 October 2016

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2016 Oct 25 1230 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

Major magstorm expected (A>=50 or K>=6)

Solar protons

Quiet

	10cm flux	Ap
25 Oct 2016	075	038
26 Oct 2016	075	050
27 Oct 2016	076	034

Bulletin

NOAA 2603 remained the sole sunspot region currently visible on the solar disk. It developed some additional sunspots in its trailing portion and was the source of a B2.0 flare peaking at 01:05UT, the strongest event of the period. Some filament and prominence eruptions were observed over the last 24 hours, but the associated coronal mass ejections (CMEs) had no earth-directed component.

Quiet flaring conditions are expected to continue, with a small chance on an isolated C-class flare.

The anticipated co-rotating interaction region (CIR) preceding the high speed stream (HSS) from the huge coronal hole (CH) arrived around 08UT and was quickly followed by a steep increase of the solar wind speed from its pre-CIR range between 380 and 420 km/s to its current value around 630 km/s (DSCOVR data). Bz, which was mostly negative over the last 24 hours, started strong fluctuations between -18 and +10 nT from about 10UT onwards. The interplanetary magnetic field (IMF) was mostly directed away from the Sun (positive). Quiet to active geomagnetic conditions were recorded, with Kp at minor storming during the 03-06UT and 09-12UT interval.

Over the next 24-48 hours, wind speeds are expected to increase to well over 700 km/s, with Bz continuing to make occasional strong negative excursions. Active to moderate storm conditions are expected, a major storming interval (K-index = 7) not excluded.

Today's estimated international sunspot number (ISN): 017, based on 10 stations.

Solar indices for 24 Oct 2016

Wolf number Catania	///
10cm solar flux	///
AK Chambon La Forêt	///
AK Wingst	018
Estimated Ap	015
Estimated international sunspot number	015 - Based on 12 stations

Noticeable events summary

Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive

All times in UTC

<< Go to daily overview page