Viewing archive of Monday, 11 May 2015

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2015 May 11 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 11 May 2015 until 13 May 2015
Solar flares

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

Geomagnetism

Minor storm expected (A>=30 or K=5)

Solar protons

Quiet

10cm fluxAp
11 May 2015165013
12 May 2015168031
13 May 2015168034

Bulletin

NOAA 2339 remains the dominant active region on the visible solar disk. Over the past 24 hours, it produced only low-level C-class flares with the emergence of some opposite polarity flux in its trailing portion. The other sunspot regions were quiet and produced at most a single low- level C-class flare. The strongest flare was a C2.5 flare peaking at 04:09UT (11 May) and was associated to a horseshoe shaped filament eruption located between active regions NOAA 2342 and 2343. Coronagraphic imagery is awaited to assess the presence and direction of any related coronal mass ejection (CME).

Further C-class flaring is expected, with a chance on an M-class flare. Unsettled to active geomagnetic conditions continued in response to the arrival of the 6 May CME. Solar wind speed declined to 350 km/s (18:00UT) and stayed at that level until about 07:00UT when it gradually started to climb to its current 380 km/s. Bz varied between -11 and +15 nT, with a sustained negative period at about -10nT between 19:00 and 02:00UT. The high speed stream of a negative coronal hole is expected to influence the geomagnetic field starting around 12 May.

Active to minor storming conditions are expected on 12 and 13 May.

Today's estimated international sunspot number (ISN): 112, based on 21 stations.

Solar indices for 10 May 2015

Wolf number Catania///
10cm solar flux160
AK Chambon La Forêt019
AK Wingst012
Estimated Ap013
Estimated international sunspot number109 - Based on 28 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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