Viewing archive of Wednesday, 21 October 2015

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2015 Oct 21 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 21 Oct 2015 until 23 Oct 2015
Solar flares

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

Geomagnetism

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

Solar protons

Quiet

10cm fluxAp
21 Oct 2015124019
22 Oct 2015122016
23 Oct 2015120008

Bulletin

Five C-class flares occurred during the past period, with NOAA active region 2436 as the main responsible source location. The strongest event was a C6.3 flare peaking at 4:34 UT on October 21. NOAA AR 2436 has developed a delta component in its trailing part. No Earth-directed CMEs were observed. Flaring at the C-level is expected, with an increased chance for an isolated M-class flare, especially from NOAA AR 2436.

The solar wind speed was relatively stable with values below 400 km/s, until about 9 UT. Since 9 UT, the solar wind speed and temperature gradually have increased and the speed reached a maximum of 480 km/s. The magnitude of the interplanetary magnetic field (IMF) went to 13 nT with a fluctuating Bz component between -9 and 11 nT. This is indicative for the start of the expected flow from the equatorial coronal hole. Currently geomagnetic conditions are quiet (K<3) to unsettled (K=3). Up to geomagnetic active (K=4) conditions are expected in the next 24 hours.

Today's estimated international sunspot number (ISN): 084, based on 09 stations.

Solar indices for 20 Oct 2015

Wolf number Catania///
10cm solar flux123
AK Chambon La Forêt016
AK Wingst014
Estimated Ap012
Estimated international sunspot number094 - Based on 19 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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