Viewing archive of Monday, 24 September 2018

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2018 Sep 24 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 24 Sep 2018 until 26 Sep 2018
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
24 Sep 2018067006
25 Sep 2018067007
26 Sep 2018067007

Bulletin

Solar activity was very low with X-ray flux remaining below B level and no spots on the visible disk. This is expected to remain so over the next days.

A filament erupted around noon September 23 from the North Eastern sector but no associated CME could be identified in coronagraph images.

Proton flux levels were at background values and are expected to remain so.

Solar wind remained slightly elevated with solar wind speed around 450 km/s. Initially, total magnetic field was elevated at 7.5-10nT with the phi angle indicating connection to negative polarity photospheric magnetic field and solar wind speed declining. But just before midnight a switch into negative polarity connection came associated with a dip in total magnetic field and a renewed slight increase of solar wind speed (reaching 480 km/s). Meanwhile the phi angle has switched back into the negative sector and solar wind is again declining (currently around 430 km/s). Solar wind speed is expected to remain slightly enhanced and may possible slightly increase under the influence of some patchy negative polarity open fields in the Southern hemisphere near the equator.

Geomagnetic conditions were quiet to unsettled (NOAA Kp 2-3 and local K Dourbes 1-3) and are expected to remain so.

Today's estimated international sunspot number (ISN): 000, based on 29 stations.

Solar indices for 23 Sep 2018

Wolf number Catania///
10cm solar flux068
AK Chambon La Forêt016
AK Wingst012
Estimated Ap013
Estimated international sunspot number000 - Based on 22 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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