Viewing archive of Friday, 21 July 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Jul 21 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 21 Jul 2017 until 23 Jul 2017
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
21 Jul 2017070016
22 Jul 2017069017
23 Jul 2017069008

Bulletin

With no spotted regions on disk, no Solar flaring activity was recorded and this is expected to remain so. A partial halo CME with angular width between 150 and 180 degrees (Cactus reports only around 130 degrees) is observed in SoHO/LASCO C2 imagery from around 18:12UT July 20. The CME originated from just around the Western limb and is directed Westward and hence will not influence Earth. Other CMEs were not recorded in coronagraph data. Solar proton fluxes are at background values and are expected to remain so.

Solar wind speed increased steadily to values of 560 km/s at 4:30UT after which a further increase was recorded with values to almost 750 km/s reported by DSCOVR. Those later values are however rather noisy and possibly not trustworthy. The previously elevated total magnetic field (around 10nT) decreased towards the end of the period to values around 5nT. Solar wind conditions are expected to remain elevated under the continued influence of the observed coronal hole high speed stream. Geomagnetic conditions were mostly quiet to unsettled (local K Dourbes 2-3 and NOAA Kp 1-3) with an isolated active period (NOAA Kp = 4) after midnight. Quiet to unsettled geomagnetic conditions, with possibly an isolated active period, are expected due to the high speed stream influence.

Today's estimated international sunspot number (ISN): 000, based on 23 stations.

Solar indices for 20 Jul 2017

Wolf number Catania000
10cm solar flux070
AK Chambon La Forêt022
AK Wingst008
Estimated Ap008
Estimated international sunspot number000 - Based on 32 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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