Viewing archive of Friday, 20 December 2013

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2013 Dec 20 1225 UTC

SIDC Forecast

Valid from 1230 UTC, 20 Dec 2013 until 22 Dec 2013
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
20 Dec 2013155008
21 Dec 2013155007
22 Dec 2013160007

Bulletin

Six C-flares and two M-flares were observed during the past 24 hours. The strongest flare was a M3.5 event taking place at the east limb, from a region that currently is rotating to the front side of the solar disk. There were no Earth-directed CME observed. The probability for C-flares remains high, around 80%, from NOAA ARs 1917, 1920, 1928, 1930 and a new region at about 40 degrees west of the central meridian. There is a substantial chance (around 60%) for more M-flares, especially from the unnumbered region currently at the east limb. An X-flare is possible but unlikely. The proton flux for >10MeV protons, measured by GOES, currently remains well below threshold levels. We are currently in a slow solar wind stream with a solar wind speed of 350 km/s and a magnitude of the interplanetary magnetic field of 5 nT (observed by ACE). Current geomagnetic conditions are quiet to unsettled (Kp<4) and are expected to remain so during the next 48 hours.

Today's estimated international sunspot number (ISN): 097, based on 15 stations.

Solar indices for 19 Dec 2013

Wolf number Catania154
10cm solar flux153
AK Chambon La Forêt013
AK Wingst006
Estimated Ap005
Estimated international sunspot number096 - Based on 15 stations

Noticeable events summary

DayBeginMaxEndLocStrengthOP10cmCatania/NOAARadio burst types
19230623192326----M3.5--/1934

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

All times in UTC

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