Viewing archive of Thursday, 14 May 2015

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2015 May 14 1230 UTC

SIDC Forecast

Solar flares

Eruptive (C-class flares expected, probability >=50%)

Geomagnetism

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

Solar protons

Quiet

	10cm flux	Ap
14 May 2015	153	014
15 May 2015	150	015
16 May 2015	148	015

Bulletin

The eruption of a filament near NOAA 2345 was accompanied by the strongest flaring event of the period, a C9.2 flare peaking on 13 May at 18:18UT. Coronagraphic imagery indicates that the bulk of the coronal mass ejection (CME) was directed to the north and away from Earth. However, difference imagery (CACTus) shows the faint outline of an asymmetric halo CME having a plane-of-the-sky speed of about 240 km/s. Provided this is not from a backside event, an impact from the shock is possible on 18 May, but the geomagnetic effects are expected to be limited. NOAA 2339 produced 2 low-level C-class flares near its leading sunspots, while the other regions were quiet. The other observed CMEs had no earth-directed component.

Further C-class flaring is expected, with a chance on an M-class flare.

Solar wind speed slowly undulated around 700 km/s as a result of the high speed stream (HSS) from the recurrent coronal hole. Bz-values were small and varied mostly between -6 and +4 nT. Only quiet to active geomagnetic conditions were observed.

Quiet to active geomagnetic conditions are expected to persist, with a chance on a minor storming episode.

Today's estimated international sunspot number (ISN): 121, based on 21 stations.

Solar indices for 13 May 2015

Wolf number Catania	200
10cm solar flux	157
AK Chambon La Forêt	037
AK Wingst	040
Estimated Ap	042
Estimated international sunspot number	122 - Based on 26 stations

Noticeable events summary

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

All times in UTC

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