Viewing archive of Thursday, 13 April 2023

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2023 Apr 13 1231 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

	10cm flux	Ap
13 Apr 2023	155	004
14 Apr 2023	155	004
15 Apr 2023	155	004

Bulletin

The solar flaring activity has been at low levels over the past 24 hours, with a total of 17 C-class flares reported. Most of the flaring activity originated from Catania sunspot group 56 (NOAA AR 3279), which recently rotated onto the visible side of the solar disk. The strongest flare was a GOES C8.5 flare with a peak time at 10:43 UT on April 13. This flare originated from Catania sunspot group 50 (NOAA AR3272), which has now crossed the central meridian. For the next 24 hours, we expect C-class flares and possibly isolated M-class flares.

During the last 24 hours there were no potentially Earth-directed coronal mass ejections detected in the available coronagraph observations.

The greater than 10 MeV proton flux was at nominal levels over the past 24 hours. An increase is possible if a significant event occurs from Catania sunspot group 50 which is now transiting the Western Hemisphere. The greater than 2 MeV electron flux has been below the 1000 pfu threshold. It is possible that an increase is observed over the coming days. The 24h electron fluence was at normal levels and is expected to below the threshold over the next 24 hours.

Over the past 24 hours, the solar wind speed was between values of 350 km/s and 420km/s. During the last 24 hours, the interplanetary magnetic field strength was about 6-8 nT and the Bz-component of the magnetic field was mostly north-ward oriented. For the coming days, we expect Earth to have minor influences from the two positive polarity coronal holes which crossed the central meridian over the past days.

During the last 24 hours the geomagnetic conditions were quiet and we expect such a geomagnetic conditions to persist in the coming hours.

Today's estimated international sunspot number (ISN): 137, based on 15 stations.

Solar indices for 12 Apr 2023

Wolf number Catania	114
10cm solar flux	154
AK Chambon La Forêt	008
AK Wingst	003
Estimated Ap	002
Estimated international sunspot number	134 - Based on 16 stations

Noticeable events summary

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

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