Viewing archive of Saturday, 15 April 2017

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2017 Apr 15 1257 UTC

SIDC Forecast

Valid from 1230 UTC, 15 Apr 2017 until 17 Apr 2017
Solar flares

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

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
15 Apr 2017073009
16 Apr 2017076011
17 Apr 2017078014

Bulletin

Solar activity was at very low levels. The strongest event was a B1.2 flare peaking at 16:21 UT yesterday. No Earth-directed CMEs were observed in available coronagraph imagery. Integral proton flux for protons with energies above 10 MeV remained at background level. B-class flaring is expected today. C-class flaring is possible from tomorrow (April 16) due to anticipated return of old active region NOAA 2644 to the visible solar disk.

Solar wind speed declined from about 380 km/s to values around 340 km/s by the end of the reporting period. The interplanetary magnetic field gradually decreased from 7.7 nT to 3.8 nT. Bz fluctuated between -5 nT and +3 nT, being positive after 06UT. Geomagnetic conditions were ranged K Dourbes between 1 and 4; NOAA Kp between 1 and 3. Geomagnetic conditions are expected to be quiet to unsettled today (April 15) and tomorrow (April 16). Active to minor storm geomagnetic conditions can be expected on April 17 due to the onset of a large positive polarity CH HSS.

Today's estimated international sunspot number (ISN): 000, based on 09 stations.

Solar indices for 14 Apr 2017

Wolf number Catania028
10cm solar flux073
AK Chambon La Forêt022
AK Wingst016
Estimated Ap016
Estimated international sunspot number018 - Based on 23 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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