Viewing archive of Tuesday, 20 October 2015

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2015 Oct 20 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 20 Oct 2015 until 22 Oct 2015
Solar flares

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

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
20 Oct 2015125008
21 Oct 2015125014
22 Oct 2015125011

Bulletin

Solar activity was restricted to a handful of C-class flares, with a C3.9 flare as strongest one peaking at 17:27 UT on October 19. The C3.9 flare originated from NOAA 2436. Regions NOAA 2434 and 2437 also contributed to some flaring. NOAA 2436 has shown some minor growth in the number of spots. Flaring activity at the C-level is expected to continue. No Earth-directed CMEs were observed in the SOHO/LASCO images.

The solar wind speed was steady between 350 and 400 km/s, while the magnetic field magnitude reached maximally 6 nT. The phi angle was variable from 22:30 UT between a positive and negative orientation. Mostly quiet (K<3) to unsettled (K=3) geomagnetic conditions were observed, which are expected to continue. There is a chance for a few episodes of active (K=4) conditions due to the moderate speed stream from an equatorial coronal hole, expected to arrive on October 21.

Today's estimated international sunspot number (ISN): 098, based on 10 stations.

Solar indices for 19 Oct 2015

Wolf number Catania111
10cm solar flux124
AK Chambon La Forêt010
AK Wingst005
Estimated Ap004
Estimated international sunspot number087 - Based on 14 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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