Viewing archive of Thursday, 23 July 2015

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2015 Jul 23 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 23 Jul 2015 until 25 Jul 2015
Solar flares

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

Geomagnetism

Minor storm expected (A>=30 or K=5)

Solar protons

Quiet

10cm fluxAp
23 Jul 2015090032
24 Jul 2015093019
25 Jul 2015095016

Bulletin

The two currently visible sunspot groups are further declining. A small active region is near the southeast limb. No C-class flares or earth- directed coronal mass ejections (CMEs) were observed.

Quiet flaring conditions are expected, with an increasing chance on an isolated C-class flare with the possible return of old active regions over the east limb during the next few days.

The glancing blow from the 19 July CME resulted in somewhat intenser geomagnetic conditions than expected. Wind speed gradually picked up from about 340 km/s around 15:30UT to a maximum near 480 km/s around 06:00UT. Bz was mostly negative from 21:00-23:00UT at -9 nT, and especially from 03:00-07:00UT at a constant -11 nT. Minor storm conditions were recorded in Dourbes at 08:00UT, and globally during the 06:00-09:00UT interval. Starting shortly after 08:00UT, the solar wind speed started to increase again from about 400 km/s to its current values between 450 and 500 km/s, while Bz is fluctuating between -6 and +6 nT.

Mostly quiet to active geomagnetic conditions are expected, with a chance on a minor storming period in response to the high speed stream from the positive CH on the northern solar hemisphere.

Today's estimated international sunspot number (ISN): 032, based on 24 stations.

Solar indices for 22 Jul 2015

Wolf number Catania038
10cm solar flux089
AK Chambon La Forêt021
AK Wingst010
Estimated Ap012
Estimated international sunspot number039 - 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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