Viewing archive of Sunday, 2 May 2021

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2021 May 02 1235 UTC

SIDC Forecast

Valid from 1230 UTC, 02 May 2021 until 04 May 2021
Solar flares

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

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
02 May 2021072022
03 May 2021071031
04 May 2021070031

Bulletin

X-ray flux has remained below C level throughout the period. Only a single B-class flare was observed from Catania group 92 (NOAA region 2820) as it was moving behind the West limb. A new region is rotating onto the disc at the South Eastern limb. Over the past days it has been the source of flaring and CME activity as observed from STEREO A, though it appears to become more quiet now. X-ray flux is likely to remain below C level.

No new Earth directed CMEs have been detected in coronagraph data.

The greater than 10 MeV proton flux was at nominal levels over the past 24 hours and is expected to remain so for the next 24 hours. The greater than 2 MeV electron flux was below the 1000 pfu event threshold. The 24h electron fluence was at normal levels ans electron fluence is expected to remain at normal levels during the next days.

Solar wind parameters were indicative of the passing of a magnetic cloud most likely associated to the April 26 CME. Solar wind speed as well as total magnetic field started increasing early in the period, with also a sudden switch of the magnetic field phi angle associated. Then from around midnight a period with pronounced negative Bz down to -6.8nT set in, followed with a long continuous rotation of the magnetic field, during which total magnetic field reached a maximum of 10.7nT. CME influences are expected to die out but enhancements in Solar wind speed are still expected over the next days associated to some positive polarity coronal holes. On May 4 Solar wind speed may increase to 500 km/s associated with the positive polarity coronal hole in the southern hemisphere.

Geomagnetic conditions were quiet to unsettled (both NOAA Kp and local K Dourbes 1-3). Geomagnetic conditions are expected to be quiet to active as further Solar wind perturbations are expected over the next days.

Today's estimated international sunspot number (ISN): 000, based on 20 stations.

Solar indices for 01 May 2021

Wolf number Catania///
10cm solar flux072
AK Chambon La Forêt015
AK Wingst007
Estimated Ap006
Estimated international sunspot number011 - Based on 23 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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