Viewing archive of Friday, 21 April 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Apr 21 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 21 Apr 2017 until 23 Apr 2017
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
21 Apr 2017081017
22 Apr 2017080007
23 Apr 2017078007

Bulletin

No C-class flares in past 24 h, they remain possible in the next 24 h. The eastern part of NOAA AR 2651 has been numbered as NOAA AR 2652, with alpha magnetic field configuration.

No Earth directed Coronal Mass Ejections (CMEs) have been detected (but there are no coronagraph images available at the moment of writing). Solar protons have remained at background levels over the past 24 hours.

The Earth is under the fading influence of a high speed stream, with solar wind speeds around 500 km/s and interplanetary magnetic fields of 4 nT. Geomagnetic conditions ranged from K=3 to K=4 and Kp between 3 and 5 in the past 24 h. Mostly unsettled geomagnetic conditions are expected in the coming hours.

Today's estimated international sunspot number (ISN): 041, based on 19 stations.

Solar indices for 20 Apr 2017

Wolf number Catania033
10cm solar flux081
AK Chambon La Forêt023
AK Wingst025
Estimated Ap028
Estimated international sunspot number029 - 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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