Viewing archive of Tuesday, 21 April 2020

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2020 Apr 21 1231 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

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

Solar protons

Quiet

	10cm flux	Ap
21 Apr 2020	068	015
22 Apr 2020	068	013
23 Apr 2020	068	007

Bulletin

Solar X-ray flux remained below B level. There are no spotted regions on disk and Solar flaring is expected to remain below C level over the next days.

There were no Earth directed Coronal Mass Ejections (CMEs) observed in the available coronagraphic imagery.

The greater than 10 MeV proton flux was at nominal levels over the past 24 hours and is expected to stay at nominal levels. The greater than 2 MeV electron flux was at nominal levels the past 24 hours. An increase of the electron flux may be expected associated to expected the high speed Solar wind conditions over the next days.

Solar wind showed the clear evolution of the magnetic cloud that started its passage yesterday and which is possibly related to the April 15 CME. Total magnetic field remained elevated over the period, reaching to around 16nT before showing a slow gradual decline to around 10nT currently. The magnetic field components showed clear signatures of magnetic field rotation. Bz became positive in the start of the period, reaching a positive peak of over 13nT before gradually rotating back into negative Bz values for thw past 3 hours. Solar wind speed remained below 380 km/s over most of the period but just recently increased to around 400 km/s. Solar wind conditions are expected to remain enhanced under the combination of the tail of the magnetic cloud passage and high speed stream influences related to both an extension of the southern polar coronal hole and later a positive polarity isolated coronal hole. An increase in Solar wind speed to between 400-500 km/s must be anticipated.

Geomagnetic conditions were initially at active to minor storm levels (NOAA Kp 5, local K Dourbes 4), but recovered to quiet to unsettled conditions as Bz became positive and Solar wind speed remained low. Some further periods of active geomagnetic conditions may be anticipated under the expected enhanced Solar wind conditions.

Today's estimated international sunspot number (ISN): 000, based on 21 stations.

Solar indices for 20 Apr 2020

Wolf number Catania	///
10cm solar flux	068
AK Chambon La Forêt	014
AK Wingst	012
Estimated Ap	015
Estimated international sunspot number	000 - Based on 31 stations

Noticeable events summary

Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive

All times in UTC

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