Publié: 2021 Apr 18 1231 UTC
Quiet conditions (<50% probability of C-class flares)
Active conditions expected (A>=20 or K=4)
Quiet
| Flux de 10 cm | Ap | |
|---|---|---|
| 18 Apr 2021 | 076 | 016 |
| 19 Apr 2021 | 075 | 013 |
| 20 Apr 2021 | 076 | 005 |
Solar activity remained at very low levels over the last 24 hours. The visible active regions NOAA 2814 (Catania 86, magnetic type Beta), NOAA 2815 (not classified) and NOAA 2016 (magnetic type Beta) remained at very low levels of activity. A B9.7 class-flare (peak time 17:17 UTC) was produced on April 17th by an active region behind the east limb and resulted in a type II radio emission. The flaring activity within the next 24 hours is expected at very low to low levels with 40% chance for a C-class flare.
A CME associated with the B9.7 class-flare was detected to leave the east limb around 16:36 UTC on April 17th. It will not impact the Earth. No other Earth-directed coronal mass ejections (CMEs) were detected in the available coronagraph imagery at the moment.
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 crossed the 1000 pfu threshold several times and is expected to remain above the threshold for long periods throughout April 18th. The 24h electron fluence reached moderate levels and is expected to remain at moderate levels in the next 24 hours.
Over the past 24 hours the solar wind parameters (ACE and DSCOVR) remained elevated from the high speed stream (HSS) currently affecting the Earth. The total magnetic field registered a maximum magnitude of 10 nT with a minimum Bz of -10 nT. The solar wind speed varied between 570 km/s and 670 km/s. The solar wind speed is expected to remain elevated throughout April 18th.
Unsettled to active geomagnetic conditions were registered over the past 24 hours under the influence of the HSS. Unsettled to active geomagnetic conditions are expected for the next 24 hours. Isolated periods of minor geomagnetic storms remain possible in case of prolonged intervals with negative Bz.
Estimation du nombre international de taches solaires (ISN) pour aujourd'hui : 016, sur la base de 17 stations.
| Nombre de Wolf, observé par Catania | /// |
| Flux solaire à 10 cm | 075 |
| AK Chambon La Forêt | 031 |
| AK Wingst | 031 |
| Ap estimé | 033 |
| Nombre international de taches solaires estimé | 018 - Basé sur 29 stations |
| Jour | Commencer | Max | Fin | Loc | Force | OP | 10cm | Catania/NOAA | Types de sursaut radio | |
|---|---|---|---|---|---|---|---|---|---|---|
| Aucun | ||||||||||
Données fournies par le Solar Influences Data analysis Center© - SIDC - Traité par SpaceWeatherLive
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