Viewing archive of Wednesday, 21 September 2016

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2016 Sep 21 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 21 Sep 2016 until 23 Sep 2016
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
21 Sep 2016087011
22 Sep 2016087007
23 Sep 2016087007

Bulletin

Solar activity was low. The Sun produced 2 low C flares in the past 24 hours. The brightest flare was a C1.7 flare released by NOAA AR 2595 with peak time 11:51 UT on September 21. Low solar activity (C flaring) is expected in the next 24 hours. Solar wind speed measured by DSCOVR decreased gradually from about 720 to about 550 km/s in the wake of a coronal hole high speed stream. Meanwhile the magnitude of the Interplanetary Magnetic Field varied beween about 1 and 6 nT. Quiet to active geomagnetic conditions (K Dourbes between 2 and 4, NOAA Kp between 2 and 4) were registered in the past 24 hours. Quiet to unsettled levels are expected on September 21, 22 and 23, with a chance for active levels (K Dourbes = 4) on September 21 as the influence of the coronal hole high speed stream wanes.

Today's estimated international sunspot number (ISN): 056, based on 13 stations.

Solar indices for 20 Sep 2016

Wolf number Catania081
10cm solar flux085
AK Chambon La Forêt026
AK Wingst021
Estimated Ap023
Estimated international sunspot number054 - Based on 31 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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