Viewing archive of Sunday, 18 October 2015

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2015 Oct 18 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 18 Oct 2015 until 20 Oct 2015
Solar flares

M-class flares expected (probability >=50%)

Geomagnetism

Minor storm expected (A>=30 or K=5)

Solar protons

Quiet

10cm fluxAp
18 Oct 2015119031
19 Oct 2015122021
20 Oct 2015125021

Bulletin

Solar flaring intensified due to a new region currently rounding the southeast solar limb. This new sunspot group produced 6 C-class flares and 2 M1 flares, the latter peaking resp. at 20:23UT and 20:42UT. NOAA 2434 produced 3 low-level C-class flares, originating from the small delta north of the main spot. NOAA 2435 and NOAA 2436 produced one C1 flare each, while NOAA 2431 was quiet. No earth-directed coronal mass ejections have been observed.

Further M-class flaring is likely, in particular from NOAA 2434 and the new region at the southeast solar limb.

Around 22:00UT, solar wind speed started a gradual rise from around 350 km/s to its current values between 400 and 450 km/s. Bz was mostly negative, with persistent values around -5 nT between 15-21UT and a strong -11 nT during the 06-09UT interval. The direction of the interplanetary magnetic field (IMF) varied wildly. In response to the persistently negative Bz, Kp reached active levels during the 18-21UT and 06-09UT intervals. Kp and local K were at minor storming levels during the last interval of the period. A negative equatorial CH may affect the geomagnetic environment late around 21 October.

Mostly quiet to active geomagnetic conditions are expected, with a chance on another minor storming episode from the moderate speed stream.

Today's estimated international sunspot number (ISN): 068, based on 11 stations.

Solar indices for 17 Oct 2015

Wolf number Catania///
10cm solar flux117
AK Chambon La Forêt019
AK Wingst013
Estimated Ap012
Estimated international sunspot number071 - Based on 11 stations

Noticeable events summary

DayBeginMaxEndLocStrengthOP10cmCatania/NOAARadio burst types
17200920232028----M1.1--/----
17203520422046----M1.5--/----

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

All times in UTC

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