Viewing archive of Monday, 19 July 2021

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2021 Jul 19 1245 UTC

SIDC Forecast

Valid from 1230 UTC, 19 Jul 2021 until 21 Jul 2021
Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

10cm fluxAp
19 Jul 2021081005
20 Jul 2021082004
21 Jul 2021081004

Bulletin

Solar activity was at very low levels over the past 24 hours. There are currently three numbered active regions on the visible disc, namely Catania sunspot group 17/NOAA 2842 (beta), NOAA 2844 (alpha) and NOAA 2845 (beta). NOAA 2842 is so far the region with most complex magnetic configuration and potential for further development, followed by active region NOAA 2845. NOAA 2844 has remained magnetically simple and is slowly decaying towards a plage region. A new small and magnetically simple active region has recently developed in the northeast quadrant and a returning active region is rotating from the north-east limb next to it. Those regions will be further monitored throughout the week. The X-ray flare activity is expected to remain at very low to low levels for the next 24 hours with 25% probability for a C-class flare mainly from NOAA 2842.

No Earth-directed coronal mass ejections (CMEs) were detected in the available coronagraph imagery.

The greater than 10 MeV proton flux was at nominal levels in the past 24 hours and is expected to remain so in the next 24 hours. The greater than 2MeV electron flux remained under the 1000 pfu threshold and is expected to remain so. The 24h electron fluence was at nominal levels and is expected to remain in the next 24 hours.

Over the past 24 hours all solar wind parameters (ACE and DSCOVR) were at low levels. The solar wind speed was in the range of 363 to 406 km/s. The total magnetic field varied between 0.9 and 7.3 nT with a weakly varying Bz component in the range of -4.2 to +5.8 nT. The interplanetary magnetic field has switched from the negative sector (directed towards the Sun) to the positive sector (directed away from the Sun).

The geomagnetic conditions over the past 24 hours were mostly quiet with several isolated unsettled periods. Mostly quiet geomagnetic conditions are expected for the next 24 hours with a slight possibility for isolated intervals with unsettled conditions.

Today's estimated international sunspot number (ISN): 045, based on 21 stations.

Solar indices for 18 Jul 2021

Wolf number Catania///
10cm solar flux080
AK Chambon La Forêt010
AK Wingst005
Estimated Ap004
Estimated international sunspot number045 - Based on 32 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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