Viewing archive of Thursday, 20 July 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Jul 20 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 20 Jul 2017 until 22 Jul 2017
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
20 Jul 2017072006
21 Jul 2017071016
22 Jul 2017071013

Bulletin

A C1.2 flare peaking at 00:02UT was recorded off the SouthWest Solar limb, apparently still related to NOAA region 2665, which is by now already well past the limb. With no spotted regions on disk the probability for C flares is very low over the next days. SDO/AIA 304 shows a filament eruption in the Southern hemisphere from 03:13UT onwards. There are no significant related signatures of this event in coronagraph data, and it is thus expected not to influence Earth. Proton flux levels are at background values and are expected to remain so.

Solar wind was nominal for most of the period with solar wind speed declining to values around 380 km/s and total magnetic field mostly under 4nT. The magnetic field phi angle switched back and forth three times as some expected sector boundary crossings occurred. The phi angle now indicates outward magnetic field orientation. Over the past hours, temperature as well as total magnetic field have been rising (to around 8nT presently) which could mark the first signs of the influence of the extension of the positive polarity northern polar coronal hole. Under the influence of the extension of the northern polar coronal hole solar wind speed may increase over the next few days. Geomagnetic conditions were quiet (local K Dourbes and NOAA Kp 1-2) and are expected to become quiet to unsettled with possibly some isolated active periods depending on the strength of the expected coronal hole influence.

Today's estimated international sunspot number (ISN): 000, based on 27 stations.

Solar indices for 19 Jul 2017

Wolf number Catania000
10cm solar flux073
AK Chambon La Forêt007
AK Wingst004
Estimated Ap003
Estimated international sunspot number000 - Based on 33 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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