Space Weather Forecast Headline: Chance of Strong Geomagnetic Storm G3 in current UTC day. Slight Chance Minor Solar Radiation Storm S1.

Analysis of Space Weather Activity over past 24 hours

Solar Activity: Solar activity has returned to Low levels over the past 24 hours, with occasional Common-class flares observed. These flares peaked with an event from a new sunspot region arriving over the northeastern solar horizon at 08/0249UTC.

There are now up to ten sunspot regions on the Earth-facing side of the Sun, with a new small magnetically unipolar spot developing near the middle of the Sun, and a returning region crossing onto the northeastern solar horizon adding to the previous eight regions in the period. The easternmost of these new regions is more complex than anticipated and the peak flares of the period have thus far come from this region - the viewing angle is currently poor but it appears at least magnetically bipolar. The other main changes in the period were generally of decay across most groups, however a region in the northeast showed new high latitude trailing spots and some reconfiguration, even as the overall area decreased.

An apparently eastward-directed Coronal Mass Ejection (CME) is becoming visible in available satellite imagery in the current UTC morning. This is tentatively associated with an event around 08/0500UTC. This has yet to be analysed but is felt unlikely to have any Earth impacts. A second CME heading apparently southward appears far-sided, but this will be confirmed as imagery becomes available. No new Earth-directed CMEs were therefore observed in available imagery in the period.

Solar Wind / Geomagnetic Activity: Solar winds have continued a slow, rather erratic decline in the wake of recent coronal hole-sourced fast wind influence. While it is still expected to arrive, there are no obvious signatures at the present time that may indicate that the 06 June CME is imminent. This is a main source of monitoring.

Solar wind speeds fell from early elevated highs, becoming slightly elevated by the period's end. Both the number of particles in the solar wind and their associated magnetic field were unremarkable and near long-term averages. The net result of the above solar wind measures was for provisionally quiet geomagnetic activity throughout.

Energetic Particles / Solar Radiation: No solar radiation storms were observed and high energy protons were near background, albeit still slightly enhanced in the wake of the recent Moderate-class X-ray flare from 08 June, having reached a peak level of 1pfu prior to the start of this reporting period (S1 is 10pfu).

Four-Day Space Weather Forecast Summary

Solar Activity: Solar activity is forecast to be Low to Moderate, with a chance of isolated Moderate-class flares and a slight chance of an isolated Strong-class flare.

Solar Wind / Geomagnetic Activity: The main driver of geomagnetic activity in the forecast period is expected to be the sole CME en route: that associated with the Moderate-class flare on 06 June. This is expected to arrive within the UTC afternoon of day 1 (08 June) and bring a shance of Strong geomagnetic storm G3 conditions, probably easing G1-G2 (Minor to Moderate) into Tuesday 09 June before a resumption of mainly quiet geomagnetic activity into days 3 and 4 (10 and 11 June).

Later on day 4, the next main coronal hole feature, may become geoeffective, bringing an increase in geomagnetic activity, with a further Chance of G1.

Energetic Particles / Solar Radiation: High energy proton flux saw a very slight rise as a result of the Moderate-class flare on 06 June, but has stayed well below the S1 Minor Radiation Storm level. This could increase further as any associated CME arrives on on day 1 (08 June), bringing a chance for a brief period of S1 Minor Storms, before quickly easing after the CME arrival occurs. There is also a slight chance of further enhancements if any notable flares occur.