Viewing archive of Monday, 21 August 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Aug 21 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 21 Aug 2017 until 23 Aug 2017
Solar flares

M-class flares expected (probability >=50%)

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
21 Aug 2017086015
22 Aug 2017087008
23 Aug 2017088007

Bulletin

Active Region (AR) 2671 (McIntosh class: Fkc; Mag.type: Beta- Gamma) has shown some evidence of flux emergence in HMI magnetogram observations; however it produced only B-class flares over the past 24 hours. The largest flare among them was a B9.3 flare peaking at 07:40UT today. New active region 2672 (McIntosh class: Dao; Mag.type: Beta) has rotated into view from the eastern limb today and already produced three C-class flares. The largest flare was C5.9 flare peaking at 03:16 UT. No Earth directed Coronal Mass Ejections (CMEs) have been detected. The greater than 10MeV proton flux remained at background levels over the past 24 hours. There are no potentially geoeffective coronal holes on the Sun. More C-class flares are expected over the next 24 hours with some probability of M-class flares. The solar wind speed has decreased from around 730 to 570 km/s over the past 24 hours. The total magnetic field strength has remained below 5 nT. The Bz component fluctuated between -4 and +4.5 nT. The geomagnetic field was at active to unsettled levels; Kp NOAA index ranged between 2-3 and local K index (Dourbes) between 1 and 4. Mostly quiet to unsettled geomagnetic conditions are expected for the next few days.

Today's estimated international sunspot number (ISN): 061, based on 19 stations.

Solar indices for 20 Aug 2017

Wolf number Catania///
10cm solar flux086
AK Chambon La Forêt020
AK Wingst023
Estimated Ap027
Estimated international sunspot number059 - 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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