Publié: 2021 Dec 04 1235 UTC
Quiet conditions (<50% probability of C-class flares)
Active conditions expected (A>=20 or K=4)
Quiet
| Flux de 10 cm | Ap | |
|---|---|---|
| 04 Dec 2021 | 081 | 010 |
| 05 Dec 2021 | 079 | 011 |
| 06 Dec 2021 | 079 | 004 |
Solar activity was at low levels over the last 24 hours. NOAA AR 2898 produced a number of low-level C-class flares near the western limb, but has now rotated over limb. NOAA AR 2902 has continued to decay. Solar activity is expected to be at very low levels, with a slight chance for a C-class flare.
A narrow Coronal Mass Ejection (CME) observed in STEREO-A COR2 from 12:54UT Dec 03 is believed to be associated with the filament eruption from the north west quadrant that was observed from 07UT Dec 03 in SDO AIA 304. It is not expected to arrive to Earth. No Earth directed CMEs have been detected in the available coronagraph imagery.
The greater than 10 MeV proton flux was at nominal levels in the past 24 hours and is expected to remain at nominal levels in the next 24 hours. The greater than 2 MeV electron flux exceeded the 1000 pfu alert threshold in the past 24 hours and is expected to exceed this threshold in the next 24 hours. The greater than 2 MeV electron fluence increased to be at moderate levels in the past 24 hours and is expected to be at moderate levels in the next 24 hours.
The solar wind speed (DSCOVR) displayed a decreasing trend at the start of the period, but began to increase again from 23UT Dec 03 to values around 530 km/s. By the end of the period the speed was just under 500 km/s. The total magnetic field fluctuated between 1 and 9 nT. Bz ranged between -7 and +7 nT. The interplanetary magnetic field phi angle was predominantly in the positive sector (directed away from the Sun). The solar wind speed is expected to be elevated on Dec 04 and with further enhancements possible on Dec 05, due to the influence of the HSS from the positive polarity Coronal Hole (CH) that began to traverse the central meridian on Dec 02.
Geomagnetic conditions were quiet to active over the past 24 hours (NOAA Kp and K-BEL recorded values of 1-3 and 1-4, respectively). Geomagnetic conditions are expected to be mostly quiet to unsettled with isolated active periods likely on Dec 04 and Dec 05, due to the expected HSS influence.
Estimation du nombre international de taches solaires (ISN) pour aujourd'hui : 019, sur la base de 08 stations.
| Nombre de Wolf, observé par Catania | /// |
| Flux solaire à 10 cm | 085 |
| AK Chambon La Forêt | 020 |
| AK Wingst | 013 |
| Ap estimé | 010 |
| Nombre international de taches solaires estimé | 025 - Basé sur 16 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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