Viewing archive of Monday, 28 September 2015

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2015 Sep 28 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 28 Sep 2015 until 30 Sep 2015
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Warning condition (activity levels expected to increase, but no numeric forecast given)

10cm fluxAp
28 Sep 2015140004
29 Sep 2015140009
30 Sep 2015135007

Bulletin

Eight sunspot groups are currently visible on the solar disk, with NOAA active regions (AR) 2422 and 2423 as most productive ones. A dozen C-class and three M-class flares were observed, with M3.6 as highest one peaking at 3:55 UT on September 28 originating from NOAA AR 2423. No associated CME was seen in coronagraphic data. A filament eruption occurred in the southeast quadrant, starting around 4:30 UT. Additional M-class flares are expected, with a slight chance for an X-class flares. Due to the position of the productive NOAA AR 2423, we issue the warning level for a potential proton event.

The Earth is inside a slow (currently around 360 km/s) solar wind flow and the interplanetary magnetic field magnitude remains maximally 6 nT. The geomagnetic conditions are quiet and are expected to remain so.

Today's estimated international sunspot number (ISN): 160, based on 16 stations.

Solar indices for 27 Sep 2015

Wolf number Catania///
10cm solar flux128
AK Chambon La Forêt008
AK Wingst004
Estimated Ap003
Estimated international sunspot number152 - Based on 27 stations

Noticeable events summary

DayBeginMaxEndLocStrengthOP10cmCatania/NOAARadio burst types
27205421002115S21W16M1.01N39/2422III/1
28034503550359S09W67M3.6SF36/2423V/2
28072707350746S22W20M1.11N39/2422

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

All times in UTC

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