Space Weather Forecast Headline: Occasional Minor radio blackouts (R1) expected. Rising likelihood of Minor or Moderate geomagnetic storms G1/G2 from midweek UTC.

Analysis of Space Weather Activity over past 24 hours

Solar Activity: Activity remained Moderate, with occasional Moderate-class flares observed from sunspot regions in both the northwest and northeast of the Sun, peaking with a mid-ranking event at 26/2257UTC.

There remain six sunspot regions on the facing side. Of these, the northernmost three regions are the most complex and dynamic. the region responsible for the peak flare in the northwest has shown some consolidation in its central spots and continues to increase in span. Also of note was a region in the northeast, with a significant increase in area observed. A third northern solar hemisphere region was less magnetically complex, with a gradual increase in span but a much more open character developing in the period. The southern solar hemisphere was much less changed, with small and stable sunspot regions here.

The peak flare of the period was associated with a radio burst that would typically be linked to an associated Coronal Mass Ejection (CME). This CME is not visible on available imagery as of the time of writing - or else the CME signature is 'polluted' by a similarly-timed event from over the western solar horizon. Analysis is ongoing, however very provisionally any ejecta on the Sun-Earth line would be approximately due to pass the Sun-Earth distance during the UTC night of Wednesday 29 into Thursday 30 April, which would potentially be coincident with the fast wind from a coronal hole. No other noteworthy CMEs were identified in the period.

Solar Wind / Geomagnetic Activity: The solar wind speed showed hesitant connection to a modest coronal hole. The solar wind speed has been slightly elevated, with a undulating trend. The number of particles in the solar wind was mainly within background, but rose to become slightly elevated during the UTC evening - perhaps suggesting faltering connection to the coronal hole. The associated magnetic field fell from Moderate early highs, with the character and magnitude changing to become more variable and smaller-scale from the UTC evening. The north-south component was variable, with no strong co- or anti-aligned periods with Earth's field (generally to lesser or greater effect respectively).

The net result of the above solar wind measures was provisionally mostly quiet geomagnetic activity.

Energetic Particles / Solar Radiation: No solar radiation storms were observed, nor even slight enhancements to proton counts in the near-Earth environment. This was despite the potentially generative large X-ray flare detailed above.

Four-Day Space Weather Forecast Summary

Solar Activity: Moderate solar activity is expected to continue at first, with occasional Moderate‑class flares and a slight chance of isolated Strong‑class flares. This flare risk expected to relax slightly through the period as confidence in the current spate of activity reduces. 

Solar Wind / Geomagnetic Activity: The aforementioned Moderate-class flare from the largest and most complex sunspot region may have produced a CME, with imagery awaited. No other CMEs feature in the forecast.

The current minor and mature fast wind should wane into Tuesday 28 April, leaving a short-lived period of quiet conditions. A second, more potent fast wind from CH48/- should develop later Wednesday 29 April, and continue into Thursday 30 April. This fast wind may interact with any inbound CME, however this aspect is very low confidence.

Mainly quiet geomagnetic activity should precede the fast wind due around midweek UTC, however this will rise to an eventual likely Minor Geomagnetic Storm G1, with a slight chance of Moderate G2 into Day 4. This forecast is subject to revision dependent on the presence of any CME influence.

Energetic Particles / Solar Radiation: There is a daily slight chance of Minor Solar Radiation Storms (S1). This risk is held constant, with a decreasing component from a region now on the far side of the Sun, but an increasing and compensatory component from the largest region on the Earth-facing side.