Viewing archive of Friday, 20 August 2021

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2021 Aug 20 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 20 Aug 2021 until 22 Aug 2021
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
20 Aug 2021075007
21 Aug 2021077007
22 Aug 2021077007

Bulletin

Two active regions are visible on the solar disk: NOAA 2857 (alpha magnetic field configuration) and 2858 (beta magnetic field configuration). There is a region behind the east limb, that will rotate into view in the coming hours, which is producing B-class flares (and CMEs). Once this region becomes visible, C-class flares can be expected.

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

The greater than 10 MeV proton flux was at background levels in the past 24 hours, and is expected to remain so in the next 24 hours. The greater than 2 MeV electron flux remained below the 1000 pfu alert threshold, while the 24h electron fluence was at normal levels over the past 24 hours. Over the next 24 hours they are expected to remain at those levels.

Over the past 24 hours the solar wind speed has been around 330 km/s. The total magnetic field strength was around 6 nT, with positive polarity (directed away from the Sun). Same conditions are expected for the next 24 hours.

Geomagnetic conditions were at quiet to unsettled levels (NOAA Kp 0-2 and K Dourbes 0-3) over the past 24 hours. Similar conditions are expected over the next 24 hours.

Today's estimated international sunspot number (ISN): 013, based on 15 stations.

Solar indices for 19 Aug 2021

Wolf number Catania026
10cm solar flux075
AK Chambon La Forêt006
AK Wingst005
Estimated Ap005
Estimated international sunspot number022 - Based on 25 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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