Viewing archive of Friday, 9 April 2021

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2021 Apr 09 1239 UTC

SIDC Forecast

Valid from 1230 UTC, 09 Apr 2021 until 11 Apr 2021
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
09 Apr 2021074004
10 Apr 2021073006
11 Apr 2021075013

Bulletin

The solar activity has been very low over the past 24 hours. The Sun is currently spotless. A small bipolar region is visible at the SE quadrant. The solar activity is expected to remain at low levels over the next 24 hours.

No Earth-directed coronal mass ejections were observed in the available coronagraphic imagery.

The greater than 10 MeV proton flux was at background levels in the past 24 hours, and is expected to stay at nominal levels in the next 24 hours. The greater than 2 MeV electron flux remained below the 1000 pfu alert threshold, with a chance to exceed this level during the next 24 hours. This is due to the influence of the high speed stream associated with the Coronal Hole at Central Meridian on April 3. The 24h electron fluence was at nominal levels and is expected to increase over the next 24 hours.

The solar wind speed decreased from between 475 to 390 km/s over the past 24 hours. The total magnetic field strength fluctuated between 1 and 5 nT. The values of the Bz component varied between -4 and +3 nT. The interplanetary magnetic field phi angle was predominantly in the positive sector (directed away from the Sun), until April 9 09:30UT when it switched to the negative sector. Solar wind conditions are expected to reflect a slow solar wind regime.

Geomagnetic conditions were at quiet levels (NOAA Kp and local K Dourbes 0-2) over the past 24 hours. Quiet conditions are expected over the next 24 hours.

Today's estimated international sunspot number (ISN): 000, based on 23 stations.

Solar indices for 08 Apr 2021

Wolf number Catania000
10cm solar flux074
AK Chambon La Forêt008
AK Wingst004
Estimated Ap003
Estimated international sunspot number000 - Based on 24 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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Active geomagnetic conditions

Observed Kp: 4
Threshold reached: 20:39 UTC

Current data suggests there is a slight possibility for aurora to appear at the following high latitude regions in the near future

Tórshavn
Oulu, Rovaniemi, Kuopio, Sodankylä, Utsjoki
Kirkenes, Tromsø, Trondheim
Arkhangelsk, Murmansk
Kiruna, Luleå, Sundsvall, Umeå

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