Viewing archive of Tuesday, 17 May 2016

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2016 May 17 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 17 May 2016 until 19 May 2016
Solar flares

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

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
17 May 2016102011
18 May 2016100012
19 May 2016096013

Bulletin

Over the past 24 hours solar activity has been low. The largest flare was a C1.8 class flare. Active Region (AR) 2544 (Macintosh class:Dai; Mag. type:Beta-gamma) produced the largest flare, the C1.8 class flare, peaking at 15:25 UT yesterday. ARs 2544 and 2545 (Cro; Beta) have been the most active regions, producing flares at the B and C class levels. ARs 2542, 2543 and 2545 have all rotated onto the West limb. 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 high probability of C-class flares and a medium 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 7 nT. The Bz component fluctuated between -7 and +7 nT. Geomagnetic conditions ranged between Kp index 2-3 (NOAA) and local K index 1-3 (Dourbes) over the past 24 hours. A positive polar coronal hole is currently positioned in the Western hemisphere of the Sun and the resulting high-speed stream (HSS) may enhance solar wind speeds. The CME produced at 15:24 UT on 15-May-2016 may also increase geo-activity at the Earth around 16:30 UT on 18-May-2016.

Today's estimated international sunspot number (ISN): 037, based on 19 stations.

Solar indices for 16 May 2016

Wolf number Catania106
10cm solar flux102
AK Chambon La Forêt022
AK Wingst///
Estimated Ap017
Estimated international sunspot number061 - Based on 31 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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