Viewing archive of Tuesday, 16 May 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 May 16 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 16 May 2017 until 18 May 2017
Solar flares

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

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
16 May 2017074017
17 May 2017074024
18 May 2017074024

Bulletin

In the past 24 hours, no C flares were observed. Very low solar activity (no C flares) is expected in the next 24 hours. Solar wind speed measured by DSCOVR increased from about 400 to a maximum around 680 km/s in the past 24 hours, with current values around 550 km/s. The magnitude of the Interplanetary Magnetic Field (IMF) varied between about 2 and 17 nT with current values around 4 nT. There were no long-lived negative Bz excursions. Continued high speed solar wind conditions are expected within the next 24 hours. Late on May 16 or on May 17, a glancing blow from the partial halo CME of May 13 may further enhance solar wind conditions. Quiet to unsettled geomagnetic conditions (K Dourbes between 2 and 3; NOAA Kp between 2 and 4) were registered in the past 24 hours. Under the influence of a high speed stream from a positive equatorial coronal hole, active geomagnetic levels (K Dourbes = 4) are possible on May 16, 17 and 18, with a chance for minor geomagnetic storm intervals (K Dourbes = 5) late on May 16 or on May 17.

Today's estimated international sunspot number (ISN): 025, based on 20 stations.

Solar indices for 15 May 2017

Wolf number Catania///
10cm solar flux071
AK Chambon La Forêt023
AK Wingst014
Estimated Ap015
Estimated international sunspot number000 - 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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