Viewing archive of Sunday, 11 April 2021

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2021 Apr 11 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 11 Apr 2021 until 13 Apr 2021
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
11 Apr 2021070006
12 Apr 2021072004
13 Apr 2021070009

Bulletin

The solar activity has been very low over the past 24 hours. The region in the SE quadrant has developed a sunspot and has had low activity. 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, were it is expected to remain during the next 24 hours. The 24h electron fluence was at nominal levels and is expected to remain at those levels over the next 24 hours.

The solar wind speed slightly increased from 320 to 380 km/s over the past 24 hours. The total magnetic field strength fluctuated between 2 and 7 nT. The values of the Bz component varied between -6 and +4 nT. The interplanetary magnetic field phi angle switched from the positive sector (directed away from the Sun) to the negative sector around April 10 02:20UT. Any effects from the high speed stream from the small, negative polarity coronal hole at central meridian April 8 have been minor. Over the next 24 hours, we can expect the last of its effects and return of solar wind parameters to background levels.

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

Today's estimated international sunspot number (ISN): 013, based on 13 stations.

Solar indices for 10 Apr 2021

Wolf number Catania///
10cm solar flux070
AK Chambon La Forêt012
AK Wingst006
Estimated Ap004
Estimated international sunspot number000 - Based on 17 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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G1 - Minor geomagnetic storm

Observed Kp: 5
Threshold reached: 23:19 UTC

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

Tórshavn
Oulu, Rovaniemi, Sodankylä
Reykjavik
Tromsø
Kiruna, Luleå

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

Kuopio
Bergen, Trondheim
Arkhangelsk
Sundsvall, Umeå
The solar wind speed is currently moderately high (525.9 km/sec.)
The strength of the interplanetary magnetic field is moderate (11.36nT), the direction is North (3.6nT).
The Disturbance Storm Time index predicts moderate storm conditions right now (-85nT)
The maximum X-ray flux of the past two hours is:
C5.75

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