Space Weather Forecast Headline: G1/Minor storm likely, chance of G2/Moderate Storm Day 1 (09 Sep).

Analysis of Space Weather Activity over past 24 hours

Solar Activity: Activity has been Low, with two minor Common-class flares in the last 24 hours. There are currently seven sunspot regions visible on the solar disc. Most are relatively simple, unipolar groups. There is only bipolar region near the north centre disc.  However, it remains magnetically simple, with no significant increase in complexity evident at this stage.

No Earth directed Coronal Mass Ejections (CMEs) have been seen in available imagery in the last 24 hours.

Solar Wind / Geomagnetic Activity: Solar winds reflected the continued, but waning influence of a coronal hole fast wind. Wind speeds were mainly elevated initially, briefly peaking above 600 km/s around 08/0600 UTC, before gradually declining to reach slightly elevated levels shortly after 08/1400 UTC. The Interplanetary Magnetic Field was weak, and so was the important north-south component. While two G1/Minor Storm intervals were observed early in the period, geomagnetic activity was mostly Unsettled and Active.

Energetic Particles / Solar Radiation: Solar radiation was at normal background levels.

Four-Day Space Weather Forecast Summary

Solar Activity: Solar Activity is likely to be Low or Very Low, but with a slight chance of Moderate-class flares, this increasing a little when a potential far side region rotates onto the disc.

Solar Wind / Geomagnetic Activity: The geomagnetic forecast has lower than average confidence. Earth is currently under the waning influence of the fast wind from CH91/+, with wind speeds of 430 km/s. However, with up to three CMEs potentially arriving at Earth early on Day 1 (09 Sep), solar wind conditions are expected to become elevated. There remains the possibility that these ejecta could interact en route and ultimately arrive as a single event. In addition, a high-speed stream from CH92/+ may arrive late on Day 3 and last into Day 4 (11-12 Sep), potentially driving solar wind speeds back above 500 km/s.

As a result, geomagnetic activity should increase from Unsettled to Active with occasional G1 (Minor) storm intervals and a chance of G2 (Moderate) storms on Day 1 (09 Sep). Activity is likely to be declining by Day 2-3 (10-11 Sep), but with a potential increase, with another chance of G1/Minor Storms later on Day 3 and into Day 4 (11-12 Sep).

Energetic Particles / Solar Radiation: Solar radiation is now at background, with a very slight chance of further enhancements above the S1/Minor Radiation Storm threshold.