Viewing archive of Saturday, 2 January 2016

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2016 Jan 02 1230 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

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

Solar protons

Warning condition (activity levels expected to increase, but no numeric forecast given)

	10cm flux	Ap
02 Jan 2016	098	020
03 Jan 2016	098	028
04 Jan 2016	100	021

Bulletin

Solar activity was moderate. NOAA AR 2473 produced a long duration M2.3 flare around midnight peaking at 00:11UT. It was associated with a dimming and radio sweeps and was responsible for an increase in the >10 MeV protons. An associated CME was detected in coronagraph data (see below). Two fairly insignificant regions have rotated onto the visible disk (now numbered NOAA 2476 and 2477). Meanwhile NOAA 2473, approaching the Western limb, remains the most probable source for flaring. Flaring at C level is expected with also a slight chance for an M flare. The >10 MeV proton flux values passed the event threshold of 10 pfu around 4:30UT, peaked at 21.5 pfu at 4:50UT and since decreased below the event threshold again. The warning condition for a proton event is maintained with NOAA AR 2473 still in the Western hemisphere. SoHO/LASCO C2 coronagraph data show a partial halo CME directed towards the South-West from 23:24UT January 1 onwards. The angular extent of the core is rather limited but counting the angular extent of the shock extensions it may be interpreted as about 200 degrees (CACTUS misinterpreted and overestimated the angular extent). Measured projected speeds are up to 1600 km/s. Given the limited angular extent of the core the CME seems directed mostly off the Sun-Earth line but a shock arrival at Earth in the afternoon of January 3 must be anticipated. No further CMEs were detected in coronagraph data. Solar wind conditions showed the recovery after the CME passage. Solar wind speed however saw a steady increase from around 420 km/s to around 490 km/s presently. Total magnetic field saw a peak of 10nT but is currently back at around 4 nT. Bz was variable and mostly above -5nT. Magnetic field phi angle was in the negative sector. Solar wind speed may further increase under the influence of a high speed stream from the extensions of the northern polar coronal hole and later, tomorrow afternoon, a shock arrival from the January 1/2 CME may be anticipated. Geomagnetic conditions were quiet to unsettled (both NOAA Kp and local K Dourbes 1-3). Geomagnetic conditions are likely to increase towards active or even minor geomagnetic storming under the influence of the high speed stream and expected shock arrival.

Today's estimated international sunspot number (ISN): 035, based on 06 stations.

Solar indices for 01 Jan 2016

Wolf number Catania	///
10cm solar flux	098
AK Chambon La Forêt	021
AK Wingst	027
Estimated Ap	024
Estimated international sunspot number	033 - Based on 10 stations

Noticeable events summary

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

All times in UTC

<< Go to daily overview page