Viewing archive of Sunday, 21 August 2022

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2022 Aug 21 1235 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

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

Solar protons

Quiet

	10cm flux	Ap
21 Aug 2022	097	015
22 Aug 2022	093	022
23 Aug 2022	092	018

Bulletin

Solar flaring activity was at low levels. The largest flare was a C2.9 flare, associated with NOAA AR 3081, peaking on August 21 at 04:59 UT. NOAA AR 3078 has decayed and is about to rotate over the west solar limb. NOAA AR 3082 was stable and quiet. NOAA AR 3084 decayed and was mostly quiet. There were to new small regions of sunspot development, the first south-east of NOAA AR3084 and the second in the northern hemisphere around N30E26. Solar flaring activity is expected to be at low levels, with C-class flares still likely and a remaining small chance for M-class flares while NOAA AR3078 remains near the west solar limb.

No new Earth directed Coronal Mass Ejections (CMEs) were detected in the available coronagraphic imagery.

The greater than 10 MeV proton flux was at nominal levels in the past 24 hours and is expected to remain so for the next days. The greater than 2 MeV electron flux crossed the 1000 pfu threshold. It is expected to again exceed the threshold in the next 24 hours. The 24h electron fluence was at nominal to moderate levels and is expected to be at nominal to moderate levels in the next 24 hours.

At the start of the period, the solar wind speed displayed a decreasing trend, with values reducing from around 560 to 500 km/s. A weak shock signature was observed at about 17:24 UT, when the solar speed increased from around 500 to 560 km/s and the density increased from 6 to 9 ppcc. The total magnetic field increased from 5 to 7nT. After the shock, the solar wind speed reached a short-lived maximum of 633 km/s before stabilizing at values near 550 km/s. The magnetic field strength also stabilized around 8nT. The magnetic field orientation was mostly in the negative sector (field directed towards the Sun). The solar wind parameters are expected to remain enhanced over the next 24 hours, due to the continued combination of effects from the high-speed stream and another possible CME glancing blow predicted for on August 22 from the CME observed on August 19.

Geomagnetic conditions were at quiet to unsettled levels at the start of the period before increasing to active levels (NOAA Kp and Local K-Dourbes recorded 4) between 21:00 UT and 00:00 UT. This was in response to the shock feature and enhanced solar wind speed. The conditions returned to quiet to unsettled levels from 01:00 UT August 21. Geomagnetic conditions for the next 24 hours are expected to be mostly at quiet to unsettled levels with further active intervals possible. This is due to the possible arrival of the CME predicted for August 22 in combination with the current waning high-speed stream and the influence of another high-speed stream from the negative polarity coronal holes that crossed the central meridian on August 18 and 19.

Today's estimated international sunspot number (ISN): 061, based on 20 stations.

Solar indices for 20 Aug 2022

Wolf number Catania	///
10cm solar flux	102
AK Chambon La Forêt	020
AK Wingst	014
Estimated Ap	016
Estimated international sunspot number	080 - Based on 25 stations

Noticeable events summary

Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive

All times in UTC

<< Go to daily overview page