Viewing archive of Wednesday, 23 August 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Aug 23 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 23 Aug 2017 until 25 Aug 2017
Solar flares

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

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
23 Aug 2017090025
24 Aug 2017091012
25 Aug 2017092005

Bulletin

Over the past 24 hours several C-class flares have been detected. The most energetic flares were two C1.9 class flares, produced by NOAA Active Region (AR) 2671. NOAA AR 2672 and Catania Sunspot group 44 produced only B-class flares. No Earth directed Coronal Mass Ejections (CMEs) have been detected. More C-class flares are expected during the next 24 hours, with a small chance of M-class flare.

Geomagnetic conditions have been disturbed due to the long period of negative Bz since early today, Kp reached 4 during 03-09 UT; the local K Dourbes also went up to 4 today. Solar wind speed is increasing again from 04 UT today and currently around 490 km/s. Simultaneously interplanetary magnetic field intensity is increasing and currently around 7.5 nT; Bz is constantly decreasing till actual value of -6 nT. Therefore, more disturbed conditions are expected in the next 24 hours with Kp up to 5.

Today's estimated international sunspot number (ISN): 066, based on 15 stations.

Solar indices for 22 Aug 2017

Wolf number Catania058
10cm solar flux090
AK Chambon La Forêt023
AK Wingst021
Estimated Ap023
Estimated international sunspot number059 - Based on 29 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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