Viewing archive of Saturday, 29 July 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Jul 29 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 29 Jul 2017 until 31 Jul 2017
Solar flares

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

Geomagnetism

Active conditions expected (A>=20 or K=4)

Solar protons

Quiet

10cm fluxAp
29 Jul 2017071003
30 Jul 2017075009
31 Jul 2017079015

Bulletin

Solar activity was at very low levels, and is expected to remain so. A barely visible sunspot group (Catania 40) is at location N19W15. No earth-directed coronal mass ejections (CMEs) were observed in available coronagraphic imagery. The greater than 10 MeV proton flux is near background levels.

Old active region NOAA 2665 is expected to round the east limb on 31 July and may gradually increase the chance on a C-class flare already on 30 July. Also the 10.7 cm radio flux is expected to increase well before the region will actually become visible.

Solar wind speed varied steadily between 470-420 km/s, showing a generally declining trend (DSCOVR). Bz oscillated between -5 and +5 nT during the entire period. The interplanetary magnetic field was mostly directed away from the Sun. A small negative equatorial coronal hole (CH) transited the central meridian from 27 till 29 July.

The geomagnetic field was at quiet to unsettled levels and is expected to remain so until the arrival of the particle stream associated with the aforementioned CH, which may start influencing the earth environment on 30 or 31 July, with active geomagnetic conditions possible.

Today's estimated international sunspot number (ISN): 000, based on 21 stations.

Solar indices for 28 Jul 2017

Wolf number Catania012
10cm solar flux070
AK Chambon La Forêt013
AK Wingst010
Estimated Ap009
Estimated international sunspot number000 - Based on 20 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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