Viewing archive of Tuesday, 4 May 2021

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2021 May 04 1235 UTC

SIDC Forecast

Valid from 1230 UTC, 04 May 2021 until 06 May 2021
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
04 May 2021072005
05 May 2021073007
06 May 2021073004

Bulletin

Solar activity was very low over the past 24 hours. No significant flares have been recorded. The solar disk is currently spotless. Solar activity is expected to be very low over the next 24 hours.

No Earth-directed Coronal Mass Ejections (CMEs) have been detected in the available coronagraphic imagery.

The greater than 10 MeV proton flux was at nominal levels over the past 24 hours and is expected to remain so for the next 24 hours. The greater than 2 MeV electron flux remained below the 1000 pfu alert threshold and is expected to remain below this level during the next 24 hours. The 24h electron fluence was at nominal levels and is expected to remain so.

The solar wind speed has been slightly enhanced with values between 390 to 500 km/s over the past 24 hours. The Bz component was mostly positive, fluctuating between -4 and +6 nT. The interplanetary magnetic field phi angle was predominantly in the positive sector (directed away from the Sun). The solar wind speed and interplanetary magnetic field are expected to continue to be enhanced on May 04, due to the ongoing influence of the high-speed stream associated with the positive polarity coronal hole in the southern hemisphere, which crossed the central meridian on April 30.

Geomagnetic conditions were quiet (NOAA Kp and local K Dourbes 1-2) over the past 24 hours. Geomagnetic conditions are expected to be quiet to unsettled over the next 24 hours, with possible isolated active periods due to the influence of the high-speed stream.

Today's estimated international sunspot number (ISN): 000, based on 17 stations.

Solar indices for 03 May 2021

Wolf number Catania///
10cm solar flux072
AK Chambon La Forêt009
AK Wingst006
Estimated Ap006
Estimated international sunspot number000 - Based on 27 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

<< Go to daily overview page

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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