Viewing archive of Tuesday, 18 April 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Apr 18 1230 UTC

SIDC Forecast

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

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

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
18 Apr 2017075010
19 Apr 2017078014
20 Apr 2017081007

Bulletin

The recurrent regions rotating over the east limb produced a C3.3 flare, peaking at 09:41 UT. Dimmings indicate that a CME may have been associated with this flare, but no coronagraph data is available yet to confirm. More C-class flares are expected, and M-class flares are possible.

No Earth directed Coronal Mass Ejections (CMEs) have been detected. Solar protons have remained at background levels over the past 24 hours.

Geomagnetic conditions have been at k = 1-2 levels. Solar wind speed is now at 325 km/s with interplanetary magnetic fields of 5 nT. A high speed solar wind from an equatorial coronal hole is expected within 24 h. Active to minor storm conditions expected.

Today's estimated international sunspot number (ISN): 023, based on 21 stations.

Solar indices for 17 Apr 2017

Wolf number Catania///
10cm solar flux075
AK Chambon La Forêt008
AK Wingst004
Estimated Ap003
Estimated international sunspot number000 - Based on 30 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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