Viewing archive of Tuesday, 20 August 2013

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2013 Aug 20 1231 UTC

SIDC Forecast

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

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

Geomagnetism

Active conditions expected (A>=20 or K=4)

Solar protons

Quiet

10cm fluxAp
20 Aug 2013128014
21 Aug 2013128020
22 Aug 2013132007

Bulletin

Flaring was eruptive featuring several C-class flares from NOAA active regions 1818, 1819 and 1825. Two CMEs were observed in the past 24 hours. The CME observed by LASCO/C2 on 19 August at 23h12 UT seems backsided and is not geo-effective. The CME observed on 20 August at 8h12 UT is associated to a large filament eruption. The CME travels with a speed of 600 km/s calculated based on STEREO data and goes mostly south of the ecliptic plane. There is a chance that Earth will be affected by the northern part of the CME structure, arriving late 23 August, possibly resulting in active to minor storm conditions. Current geomagnetic conditions are quiet to unsettled. Periods of enhanced geomagnetic activity are possible (unsettled to active) for the next 48 hours, in relation to the arrival of the equatorial coronal hole high speed stream and the CME of August 17.

Today's estimated international sunspot number (ISN): 084, based on 14 stations.

Solar indices for 19 Aug 2013

Wolf number Catania///
10cm solar flux128
AK Chambon La Forêt009
AK Wingst006
Estimated Ap005
Estimated international sunspot number091 - Based on 24 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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