Viewing archive of Sunday, 18 September 2016

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2016 Sep 18 1358 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

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

Solar protons

Quiet

	10cm flux	Ap
18 Sep 2016	080	015
19 Sep 2016	078	008
20 Sep 2016	077	007

Bulletin

Solar activity was low in the past 24 hours. Only one B4.1 flare was observed today (18-Sep-2016) from active region (AR 2592) which peaked at 02:51 UT. One additional active region is presently observed on the solar disk with the simple magnetic configuration. No Earth-directed CMEs were observed. There is a negative polarity coronal hole presently observed in the geoeffective position of the visible solar disk. Solar protons have remained at background levels over the past 24 hours. Solar activity is expected to be low with a small probability of C-class flares. The variations of the solar wind parameters slightly increased due to the influence of the negative polarity coronal hole currently observed on the visible side of the solar disk. Solar wind speed gradually increased from 310 to 370 km/s. The magnitude of the Interplanetary Magnetic Field (Bt) has increased from 5 to 7 nT, while Bz has fluctuated between +7 and -7 nT during last 24 hr being mainly negative. In the past 24 hours geomagnetic conditions have been quiet ( K Dourbes between 0 and 2; NOAA Kp between 0 and 2). However today at 12:00 UT both K Dourbes and Kp NOAA increased till 3 as the response to the solar wind parameters perturbations. Geomagnetic conditions are expected to be active over next 9-12 hours (Kp NOAA may increase till 4), then geomagnetic conditions are expected to return to mostly quiet levels over the next few days in view of the gradually waning effects of the coronal hole elevated speed stream.

Today's estimated international sunspot number (ISN): 038, based on 18 stations.

Solar indices for 17 Sep 2016

Wolf number Catania	///
10cm solar flux	080
AK Chambon La Forêt	008
AK Wingst	003
Estimated Ap	003
Estimated international sunspot number	014 - Based on 25 stations

Noticeable events summary

Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive

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