Space Weather Forecast Headline: Further Moderate flares (R1/R2 blackouts) expected. Chance of isolated G1/Minor Geomagnetic Storm intervals from Coronal Mass Ejection (CME) or fast wind effects Days 2-3 (26-27 Apr).

Solar Activity: Activity is currently Moderate with several Moderate-class flares observed in the past 24 hours. The largest of these occurred at 24/2259UTC from the large complex that straddles the southwest limb. This broad cluster of regions carry a large percentage of the current flare risk, with the spots magnetically connected and a large amount of flux associated with them, suggesting a potential for Strong flares. However, this group is becoming increasingly difficult to analyse due to its location on the disc. There are currently seventeen regions on the visible disc. Of these, a region in the northwest has developed magnetic complexity. A relatively large region in the southeast is exhibiting minor magnetic complexity.

Multiple Coronal Mass Ejections (CMEs) have been observed in coronagraph imagery over the previous 24hrs, with some potential for the odd glancing blow at Earth. A prominence eruption across the eastern limb at 25/1100UTC has produced a CME but this is not expected to have an Earth-directed component.

Solar Wind / Geomagnetic Activity: Solar winds were at background levels. Wind speeds have gradually declined from 380km/s and are currently around 320 km/s. The Interplanetary Magnetic Field was weak, with the north-south component also varying weakly, but has been predominantly negative (southward) oriented since 25/0500UTC. Geomagnetic activity was Quiet (Kp 0-1). 

Energetic Particles / Solar Radiation: The count rate of energetic particles (high energy protons) remained at background levels with no solar radiation storms observed.

Four-Day Space Weather Forecast Summary

Solar Activity: Moderate activity is expected to continue at first, with a very slight chance of isolated Strong flares Days 1-2 (25-26 Apr). The complex cluster of regions in the southwest will fully rotate off the disc late on Day 2 (26 Apr). The flare risk is then expected to decline during Day 3 (27 Apr) and Day 4 (28 Apr) as these regions rotate well away from the west limb. There remains a flare risk from other regions on the visible disc however, with the chance of Moderate flares continuing throughout.

Solar Wind / Geomagnetic Activity: There is a risk of CMEs passing close to Earth throughout the period, largely missing ahead and to the south of our orbit. The greatest potential for any impacts is thought likely to be later Day 2 into early Day 3 (26-27 Apr). Otherwise solar winds are currently at background levels. Solar winds are currently at background levels with enhancement from two coronal hole high speed streams expected to connect during Days 2-3 (26-27 Apr). Although additional enhancement from a further stream of coronal hole fast winds is possible late Day 3. The combined contributions are likely to result in an increase in wind speeds during this period, perhaps reaching 500-550 km/s. Moderate confidence in wind speeds as the coronal holes are persistent features and were present on the last rotation resulting in an uptick in wind speeds to Elevated levels.

Geomagnetic activity is likely to be Quiet to Unsettled (Kp 0-3) at first. This has the potential to become Unsettled to Active (Kp 3-4) with a chance Days 2-3 (26-27 Apr) of G1/Minor Storm (Kp 5) intervals, either under Coronal Mass Ejection (CME) or fast wind influence, or perhaps a combination of both. The risk should decline into Day 4 (28 Apr).

Energetic Particles / Solar Radiation: The count rate of energetic particles (high energy protons) is likely to persist at background levels, but with a slight chance of reaching the S1/Minor Radiation Storm level throughout this period.