Viewing archive of Thursday, 18 May 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 May 18 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 18 May 2017 until 20 May 2017
Solar flares

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

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
18 May 2017072010
19 May 2017072020
20 May 2017072024

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 decreased from about 470 to 400 km/s in the past 24 hours. The magnitude of the Interplanetary Magnetic Field (IMF) varied between about 1 and 10 nT. Enhanced solar wind conditions are expected to start in the second half of May 19 due to the arrival of a high speed stream from a negative equatorial coronal hole. Quiet to unsettled geomagnetic conditions (K Dourbes between 2 and 3; NOAA Kp between 1 and 4) were registered in the past 24 hours. Quiet to unsettled levels are expected on May 18 and the first half of May 19, with a slight chance for active geomagnetic levels (K Dourbes = 4). Active (K Dourbes = 4) to minor storm conditions (K Dourbes = 5) are possible in the second half of May 19 and on May 20, due to the expected high speed stream.

Today's estimated international sunspot number (ISN): 023, based on 14 stations.

Solar indices for 17 May 2017

Wolf number Catania044
10cm solar flux071
AK Chambon La Forêt///
AK Wingst009
Estimated Ap009
Estimated international sunspot number012 - 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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