Viewing archive of Wednesday, 18 May 2016

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2016 May 18 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 18 May 2016 until 20 May 2016
Solar flares

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

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
18 May 2016104013
19 May 2016106016
20 May 2016105014

Bulletin

Over the past 24 hours solar activity has been low. The largest flare was a B4.1 class flare, produced by Active Region (AR) 2544 (Macintosh class:Cao; Mag. type:Beta-gamma). All other ARs have been quiet. AR 2544 has exhibited significant flux emergence and cancellation in HMI observations, which may lead to further flares. Solar protons have remained at background levels over the past 24 hours. Solar activity is expected to remain low over the next 24 hours with a medium probability of C-class flares and a low probability of M-class flares. The solar wind speed has remained around 550 km/s over the past 24 hours. The total magnetic field strength has fluctuated around 6 nT. The Bz component fluctuated between -6 and +6 nT. Geomagnetic conditions ranged between Kp index 2-3 (NOAA) and local K index 1-3 (Dourbes) over the past 24 hours. A large Northern positive polar coronal hole is currently positioned in the central longitudes of the Sun and will rotate into the Western hemisphere in the coming days, the resulting Co-rotating Interaction Region (CIR) and high-speed stream (HSS) may enhance geo- activity. The CME produced at 15:24 UT on 15-May-2016 has shown no influence on the Earth yet, but may in coming hours.

Today's estimated international sunspot number (ISN): 030, based on 18 stations.

Solar indices for 17 May 2016

Wolf number Catania///
10cm solar flux103
AK Chambon La Forêt025
AK Wingst016
Estimated Ap017
Estimated international sunspot number037 - Based on 26 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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