Viewing archive of Friday, 27 May 2016

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2016 May 27 1230 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

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

Solar protons

Quiet

	10cm flux	Ap
27 May 2016	088	014
28 May 2016	087	013
29 May 2016	086	013

Bulletin

The two strongest flares of the period were a C1.1 and a C1.0 flare peaking at 13:36UT and 13:51UT on 26 May. They were produced by resp. NOAA 2548 and 2546, the latter which has rotated over the western solar limb. NOAA 2548 seems to have stabilized, but is still showing some filaments near the main spot. No earth-directed coronal mass ejections (CMEs) were observed. A filament to the southeast of NOAA 2548 had disappeared by the end of the period.

Mostly quiet conditions are expected, with a chance on an isolated C-class flare.

Shortly after 22:00UT, the direction of the Interplanetary Magnetic Field turned from away to towards the Sun as a result of the arrival of the anticipated sector boundary crossing and co-rotating interaction region (CIR). In response to the moderate speed stream from the southern coronal hole (CH), solar wind speed started a gradual increase from about 350 km/s around 01:00UT to the current values near 450 km/s. Bz remained steady at low values till about 01:00UT, when it started varying between mostly -7 and +5 nT. Quiet to unsettled geomagnetic conditions were observed.

Quiet to unsettled geomagnetic conditions are expected to persist, with a chance on an active episode as the effects of the moderate speed stream from the CH fully unfold. Similar effects from the wind stream from the negative northern CH are expected for 28-29 May. During the entire period, there is a small chance on a minor storming episode.

Today's estimated international sunspot number (ISN): 037, based on 21 stations.

Solar indices for 26 May 2016

Wolf number Catania	038
10cm solar flux	092
AK Chambon La Forêt	010
AK Wingst	004
Estimated Ap	003
Estimated international sunspot number	034 - Based on 37 stations

Noticeable events summary

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

All times in UTC

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