Minor C9.9 solar flare erupts at 05:05 UTC on November 5, 2025

A minor C9.9 solar flare erupted at 05:05 UTC on November 5, 2025.

Today’s flares include a C4.3 flare that peaked at 00:58 UTC, a C6.2 flare that peaked at 01:55 UTC, and a C8.0 flare that peaked at 03:01 UTC, all originating from region 4274.

In 24 hours to 00:30 UTC on November 5, solar activity reached very high levels due to an X1.8 flare and an X1.1 flare in the preceding period, with continuous activity from region 4274 contributing to the elevated level.

There is a 65% probability for R1 – Minor to R2 – Moderate radio blackouts, and a 15% probability for R3 – Strong radio blackouts owing to the continued activity and complex structure of region 4274.

Active sunspot regions presently observed on the Earth-facing solar disk include AR 4272 (N22E36 – Beta), AR 4273 (S12W01 – Beta-Gamma), AR 4274 (N24E53 – Beta-Gamma-Delta), and AR 4275 (N07E61 – Beta-Gamma).

Over the past 24 hours, the greater than 2 MeV electron flux remained above 1 000 pfu during diurnal maxima, but is trending downward as Earth exits the geoeffective position of the coronal hole high speed stream. The greater than 10 MeV proton flux was at background levels. Electron levels are expected to continue decreasing through November 6, followed by an increase on November 7 as a new high speed stream becomes geoeffective. Greater than 10 MeV protons could become slightly elevated following the recent X-class flare but should remain below threshold levels.

Solar wind parameters during the past 24 hours reflected waning high speed stream influences, with interplanetary magnetic field strength between 6–8 nT and solar wind speeds decreasing from 450 km/s towards 400 km/s. Parameters are likely to remain at nominal levels through November 6 before becoming enhanced on November 6–7 with the arrival of the next coronal hole high speed stream and potential CME interactions.

The geomagnetic field was quiet to unsettled as high speed stream effects diminished. Conditions are expected to remain at current levels through November 6, with a likelihood for G1 – Minor geomagnetic storming late on November 6 into November 7, and a slight chance for G2 – Moderate storming as the new high speed stream and potential CME arrivals influence geospace.