Viewing archive of Saturday, 2 September 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Sep 02 1235 UTC

SIDC Forecast

Valid from 1230 UTC, 02 Sep 2017 until 04 Sep 2017
Solar flares

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

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
02 Sep 2017094024
03 Sep 2017093012
04 Sep 2017092006

Bulletin

Over the past 24 hours solar activity remained low. There were four sunspot regions, and only Catania group 47 (NOAA region 2674) sowed some flaring activity and produced four C-class flares. The largest one was a C2.0-class flare with a peak-time at 15:37 UT September 1. Catania group 43 (NOAA region 2672) is on West solar limb and will disappear in a couple of hours. The photospheric magnetic complexity of Catania group 47 (NOAA region 2674) has increased, therefore we expect a higher probability of C-class flare with possibly the occurrence of an M-class flare. A new active region is turning over the East solar limb, which might start to also contribute the solar activity.

No Earth directed Coronal Mass Ejections (CMEs) have been detected in the available coronagraph imagery and the solar protons remains at background level.

The Earth remained in the fast solar wind with the speed that has slowly decreased from 700 to about 600 Km/s. The interplanetary magnetic field magnitude has also slowly decreased from 10 nT to about 4 nT, and the Bz component fluctuating between -5 and 2 nT.

The geomagnetic conditions were active with K-Dourbes ranging between 2 and 4, and Kp-NOAA between 2 and 5. The observed moderated storm (Kp-NOAA = 5) on September 2, between 03:00 and 09:00 UT was due to Bz component that stayed negative for a longer period. The geomagnetic conditions are expected to vary between unsettled to active conditions until the high speed stream has fade, and then to reduce to quiet to unsettled on September 3.

Today's estimated international sunspot number (ISN): 063, based on 22 stations.

Solar indices for 01 Sep 2017

Wolf number Catania061
10cm solar flux093
AK Chambon La Forêt030
AK Wingst020
Estimated Ap020
Estimated international sunspot number069 - Based on 31 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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