Viewing archive of Monday, 31 July 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Jul 31 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 31 Jul 2017 until 02 Aug 2017
Solar flares

C-class flares expected, (probability >=50%)

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
31 Jul 2017073013
01 Aug 2017075013
02 Aug 2017075007

Bulletin

Returning Active Region NOAA 2665 produced a B9.2 flare which peaked at 9:12 UT on July 31. C flares from NOAA 2665 are possible in the next 48 hours, with a chance for M flares. No earth-directed Coronal Mass Ejections (CMEs) were observed in available coronagraphic imagery. The greater than 10 MeV proton flux was at nominal levels.

Solar wind speed measured by DSCOVR varied between about 320 and 380 km/s in the past 24 hours. Bz oscillated between about -5 and 4 nT. The Interplanetary Magnetic Field (IMF) was directed away from the Sun and its magnitude ranged between about 1 and 7 nT. Quiet geomagnetic conditions (K Dourbes between 0 and 2; NOAA Kp between 0 and 1) were registered in the past 24 hours. Active levels (K Dourbes = 4) are possible on July 31, August 1 and 2 due to the expected arrival of a high speed stream from a small negative equatorial coronal hole, with a slight chance for minor storm conditions (K Dourbes = 5).

Today's estimated international sunspot number (ISN): 000, based on 25 stations.

Solar indices for 30 Jul 2017

Wolf number Catania///
10cm solar flux070
AK Chambon La Forêt007
AK Wingst005
Estimated Ap005
Estimated international sunspot number014 - Based on 26 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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