Viewing archive of Thursday, 15 July 2021

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2021 Jul 15 1231 UTC

SIDC Forecast

Solar flares

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

Geomagnetism

Quiet (A<20 and K<4)

Solar protons

Quiet

	10cm flux	Ap
15 Jul 2021	074	004
16 Jul 2021	076	001
17 Jul 2021	074	001

Bulletin

Solar activity was at very low levels, with only B-class flares produced in the last 24 hours. NOAA Active Region (AR) 2842 (Catania sunspot group 17) continues to decay, NOAA AR 2843 (Catania sunspot group 18) has lost some magnetic complexity, while NOAA 2841 has now become a plage region. For the next 24 hours the solar activity is expected to remain very low with a small change of a C-class flare.

No Earth directed Coronal Mass Ejections (CMEs) have been detected in the available coronagraph 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 High Speed Stream (HSS) initially predicted to arrive on July 11, arrived weakened at 09:00UT July 14 and had a minor effect on the solar wind. The solar wind speed increased from 340 to 440 km/s during the last 24 hours. The total magnetic field varied between 1 and 13 nT in the last 24 hours. The Bz was predominantly negative during the last 24 hours, with values varying between -12 and 6 nT. The interplanetary magnetic field phi angle was predominantly negative (directed towards the Sun) during the last 24 hours. The solar wind conditions are expected to reflect a slow solar wind regime for the next 24 hours.

Geomagnetic conditions were quiet to active both globally and locally (NOAA Kp index and K Dourbes 1-4) over the past 24 hours. This was due to the arrival of the HSS mentioned above. They are expected to be at quiet levels for the next 24 hours.

Today's estimated international sunspot number (ISN): 017, based on 17 stations.

Solar indices for 14 Jul 2021

Wolf number Catania	037
10cm solar flux	072
AK Chambon La Forêt	021
AK Wingst	019
Estimated Ap	018
Estimated international sunspot number	027 - Based on 21 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