Viewing archive of Thursday, 26 September 2013

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2013 Sep 26 1209 UTC

SIDC Forecast

Valid from 1230 UTC, 26 Sep 2013 until 28 Sep 2013
Solar flares

Quiet conditions (<50% probability of C-class flares)

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
26 Sep 2013111004
27 Sep 2013109005
28 Sep 2013109007

Bulletin

The Sun is quiet when it comes to flaring activity. NOAA AR 1850/Catania 83 produced a few B-flares. We expect that the X-ray radiation stays at a low level. The solar wind speed peaked on September 25 around 450 km/s and decreased slowly to a speed of 350 km/s today, September 26. Late September 25, the Earth crossed a sector boundary (SB). The interplanetary magnetic field changed from an inward to an outward direction, the density of the solar wind plasma has changed slightly. The SB crossing did not have geomagnetic consequences. A small northern coronal hole (between 35° and 50° latitude) will pass the central meridian today, September 26. We expect the geomagnetic conditions to stay quiet for the next 48 hours.

Today's estimated international sunspot number (ISN): 038, based on 13 stations.

Solar indices for 25 Sep 2013

Wolf number Catania099
10cm solar flux111
AK Chambon La Forêt005
AK Wingst004
Estimated Ap004
Estimated international sunspot number054 - Based on 23 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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