Space Weather Forecast Headline: Further Moderate flares expected (R1/R2 blackouts). Chance of isolated Minor Geomagnetic Storm intervals from peripheral coronal mass ejection effects.

Solar Activity: Moderate with four Moderate flares observed, the largest observed from a active region in the southeast. Sixteen sunspot regions, fifteen numbered, currently feature on the visible side of the solar disc. This includes a broad complex in the southwest, with spots magnetically connected and complex in places. Several other regions are also moderately sized, in general these remain more stable with simpler configurations, however a region in the southeast and another in the northern disk have seen further development and likely represent an increasing flare risk.

Multiple coronal mass ejections (CMEs) observed in available imagery over the previous 24hr, although limited clear Earth directed potential. The most likely candidates a recent CME associated with a Moderate flare from the southwest at 22/2116UTC, perhaps bringing a glancing risk into day 4 (27 Apr). We await model output and further analysis of the CME associated with another Moderate flare from the same region at 23/1710UTC.

Solar Wind / Geomagnetic Activity: Solar winds were slightly elevated to background throughout, on a steady trend, ending the period at around 370km/s. The Interplanetary Magnetic Field (IMF) Bt, was weak, with the important north-south component, Bz, varying weakly. Geomagnetic activity was Quiet to Unsettled (Kp1-3). 

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

Four-Day Space Weather Forecast Summary

Solar Activity: Occasional Moderate flares are expected to continue, with a slight chance of isolated Strong flares. The greatest risk from the large complex of sunspot regions in the southwest.

Solar Wind / Geomagnetic Activity: There are several Coronal Mass Ejections that have been modelled and are anticipated to pass close to Earth through the period, with the potential for glancing interactions. This gives low confidence for detail of the geomagnetic forecast. Solar winds have now eased to Slow levels, and in the absence of CME influence should continue at similar levels to start the period. A further enhancement possible by day 3 (26 Apr) in association with another coronal hole currently near centre disc, likely seeing winds increasing back towards slightly elevated or elevated levels though into day 4 (27 Apr). 

Overall, geomagnetic activity expected to remain mainly Quiet initially, with Unsettled intervals. However, any CME arrivals will give a chance of Active intervals and a chance of G1 Minor Storms, this risk peaking into day 2 (25 Apr). Activity perhaps more generally increasing by later day 3 (26 Apr) with Unsettled to Active conditions expected by the end of the period given faster solar winds.

Energetic Particles / Solar Radiation: The count rate of energetic particles (high energy protons) is expected to persist at background levels, but with a chance of rising with any larger flares that occur. This will bring a slight chance of reaching the S1 Solar Radiation Storm levels throughout the period.