Viewing archive of Wednesday, 18 September 2013

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2013 Sep 18 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 18 Sep 2013 until 20 Sep 2013
Solar flares

Eruptive (C-class flares expected, probability >=50%)

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
18 Sep 2013099011
19 Sep 2013103007
20 Sep 2013109007

Bulletin

There are currently seven numbered sunspot groups on the solar disc. Solar activity is still low, with only one C-class flare reported during last 24 hours. The C3.9 flare (peaked at 03:15 UT, on September 18) originated from the NOAA AR 1846 which just turned from behind the east solar limb. The C-class flares are possible, in particular from the NOAA ARs 1846 and 1847. The solar wind speed slightly increased and it is now about 400 km/s. The interplanetary magnetic field magnitude is currently 5 nT. The occasional short intervals of negative Bz component of the interplanetary magnetic field resulted in K=3, as reported by local stations Dourbes and Izmiran. The geomagnetic conditions are quiet to unsettled and expected to remain so in the following 48 hours.

Today's estimated international sunspot number (ISN): 044, based on 11 stations.

Solar indices for 17 Sep 2013

Wolf number Catania024
10cm solar flux099
AK Chambon La Forêt016
AK Wingst010
Estimated Ap009
Estimated international sunspot number029 - 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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