Viewing archive of Wednesday, 1 September 2021

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2021 Sep 01 1236 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

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

Solar protons

Quiet

	10cm flux	Ap
01 Sep 2021	085	007
02 Sep 2021	085	025
03 Sep 2021	085	007

Bulletin

Apart from a single C1.2 flare from Catania group 32 (NOAA 2860), X-ray flux remained below C level. Catania group 32 (NOAA 2860) shrunk and reduced in complexity (now Beta type of its photospheric magnetic field). It remains a likely source for C class flaring with only a small chance for M class flare remaining. The new region rotating onto the disc in the North East appears to be spotless.

There were no new Earth directed CMEs observed in available coronagraph data.

The greater than 10 MeV proton flux was at background levels and we expect it will remain so in the next 24 hours. The greater than 2 MeV electron flux reached again above the 1000 pfu threshold during its diurnal maximum both yesterday and today. The 24h electron fluence is at moderate levels and we expect it to follow slowly decaying trend.

A negative polarity coronal hole in the southern hemisphere is about to start crossing the central meridian. It is expected to influence Solar wind conditions near Earth on September 5.

Solar wind is in a slow Solar wind regime with no obvious signs of arrival of the August 26 CME. Solar wind speed was mostly in the 310-350 km/s range. Interplanetary magnetic field was below or around 5nT with an unremarkable Bz component. The orientation of the Interplanetary magnetic field was mostly towards the Sun. Solar wind is likely to become enhanced again with an expected arrival of the August 28 CME tomorrow before noon.

Geomagnetic conditions have been quiet (NOAA Kp 0-2 and local K Dourbes 1-2 ). Active conditions are possible over the next 24-48 hours with the possible August 28 CME arrival.

Today's estimated international sunspot number (ISN): 036, based on 11 stations.

Solar indices for 31 Aug 2021

Wolf number Catania	033
10cm solar flux	084
AK Chambon La Forêt	009
AK Wingst	008
Estimated Ap	007
Estimated international sunspot number	040 - Based on 35 stations

Noticeable events summary

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

All times in UTC

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