Viewing archive of Friday, 11 September 2015

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2015 Sep 11 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 11 Sep 2015 until 13 Sep 2015
Solar flares

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

Geomagnetism

Major magstorm expected (A>=50 or K>=6)

Solar protons

Quiet

10cm fluxAp
11 Sep 2015086030
12 Sep 2015087022
13 Sep 2015089017

Bulletin

Solar activity remains to be low, with no flares above the B-level reported during last 24 hours. We expect this low solar activity to persist with possibility of an isolated C-class flare in the coming hours. The flaring activity can be also expected from still unnumbered active region currently situated at the east solar limb. No Earth directed CMEs were observed in the last 24 hours.

The fast flow associated with the elongated equatorial coronal hole (20S to 20N) which crossed central meridian in the morning of September 08, has arrived this morning at about 06:40 UT. The solar wind speed has increased from about 450 km/s up to the current value of about 690 km/s. Simultaneously with the increase of the solar wind speed, the interplanetary magnetic field magnitude jumped to the value of about 20 nT (its present value is about 7 nT). The long interval of the negative value of the Bz component of the interplanetary magnetic field (down to -17nT) and the fast solar wind induced geomagnetic storm conditions, NOAA reported Kp=7 and local station Dourbes reported K=6. The fast flow from the low latitude extension of the northern polar coronal hole which crossed the central meridian in the morning of September 09 is expected to arrive at the Earth late today or morning of September 12. We expect active to geomagnetic storm conditions to persist in the coming hours.

Today's estimated international sunspot number (ISN): 079, based on 18 stations.

Solar indices for 10 Sep 2015

Wolf number Catania045
10cm solar flux084
AK Chambon La Forêt030
AK Wingst019
Estimated Ap018
Estimated international sunspot number043 - Based on 29 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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