Viewing archive of Thursday, 16 September 2021

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2021 Sep 16 1231 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

	10cm flux	Ap
16 Sep 2021	076	001
17 Sep 2021	074	001
18 Sep 2021	076	007

Bulletin

The solar activity was at very low levels with no C-class flare activity over the past 24 hours. The only significant feature observable from Earth is NOAA plage 2870 who is not expected to produce any C-class flares. There is a small chance of C-class activity from a returning active region for the next 24 hours.

No Earth-directed CMEs were detected in the available coronagraph imagery over the past 24 hours.

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

The Solar Wind (SW) parameters measured by ACE and DSCOVR are typical of the slow wind regime. The SW speed dropped from 430 to 310 km/s over the last 24 hours. The total magnetic field (Btot) varied 0.9 and 5.2 nT and the Bz magnetic field component varied between -3.5 and 3.7 nT during the past 24 hours. The interplanetary magnetic field was mainly positive (directed away from the Sun) during the last 24 hours. The solar wind parameters are expected to remain in the slow SW regime in the next 24 hours.

The geomagnetic conditions over the past 24 hours were globally and locally quiet (NOAA Kp index and K Dourbes 1-2). They are expected to become quiet both globally and locally in the next 24 hours.

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

Solar indices for 15 Sep 2021

Wolf number Catania	011
10cm solar flux	075
AK Chambon La Forêt	008
AK Wingst	006
Estimated Ap	006
Estimated international sunspot number	011 - Based on 18 stations

Noticeable events summary

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

All times in UTC

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