Viewing archive of Monday, 19 March 2018

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2018 Mar 19 1230 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
19 Mar 2018	068	023
20 Mar 2018	068	013
21 Mar 2018	067	010

Bulletin

Solar activity was at very low levels. Active region NOAA 2702 decayed further into a spotless faculae field and was quiet. No earth- directed coronal mass ejection (CMEs) were observed in available coronagraphic imagery. The greater than 10 MeV proton flux was at nominal levels.

Solar activity is expected to remain at very low levels.

Earth is under the influence of the high speed stream (HSS) from a negative polarity coronal hole (CH). Solar wind speed gradually increased from initial values around 510 km/s to peak values near 610 km/s at 04UT, before declining to its current 520 km/s (DSCOVR). A stretch of negative Bz was observed between 17 and 22UT, with values as low as -9 nT. During the second half of the period, Bz varied between mostly -3 and +3 nT. The interplanetary magnetic field was mostly directed towards the Sun.

In response to the period of sustained negative Bz, geomagnetic storming conditions were observed from 18UT on 18 March till 03UT on 19 March, with Kp reaching 6 (moderate storm) during the 21-24UT interval. Dst values were modest at only -36nT.

Small near-equatorial CHs and two extensions from the negative polarity southern polar CH are moving into geo-effective positions. The associated wind streams may affect the earth environment in the next few days. Unsettled to active conditions are expected, with a chance on an isolated minor storming episode.

Today's estimated international sunspot number (ISN): 000, based on 16 stations.

Solar indices for 18 Mar 2018

Wolf number Catania	///
10cm solar flux	069
AK Chambon La Forêt	039
AK Wingst	025
Estimated Ap	024
Estimated international sunspot number	007 - Based on 16 stations

Noticeable events summary

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

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