Viewing archive of Saturday, 21 December 2019

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2019 Dec 21 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 21 Dec 2019 until 23 Dec 2019
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
21 Dec 2019071006
22 Dec 2019071007
23 Dec 2019071007

Bulletin

Solar X ray flux remained below B level throughout the period. There are no spotted regions on disk and X-ray flux is expected to remain at background levels.

A filament erupted from the far Southern hemisphere this morning (between 6-9UT) but coronagraph data do not (yet) show any associated CME signatures. No Earth-directed CME's were detected in coronagraph images.

A low latitude negative polarity coronal hole started transiting the central meridian at midnight and may cause enhancements of Solar wind conditions starting December 24.

Solar high energy proton fluxes were at background levels and are expected to remain so. The >2MeV electron flux is enhanced (though not over the event threshold) as a consequence of the high speed stream passage and is still expected to rise before starting a gradual recovery.

Solar wind showed a further decaying trend in the wake of the high speed stream. Solar wind speed decreased slowly from around 450 km/s to under 400 km/s. Total magnetic field was in a nominal 4-5nT regime. The magnetic field phi angle was in the positive sector. Solar wind conditions are expected to become and remain nominal in the coming days.

Geomagnetic conditions were quiet (local K Dourbes 1-2 and NOAA Kp 0-2) and this is expected to persist.

Today's estimated international sunspot number (ISN): 000, based on 12 stations.

Solar indices for 20 Dec 2019

Wolf number Catania000
10cm solar flux070
AK Chambon La Forêt009
AK Wingst008
Estimated Ap006
Estimated international sunspot number000 - Based on 14 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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