Discussion: Tonight moisture begins to advect from the south with further warm air, slowly bringing in energy with it. MUCAPE in excess of 3000 J/KG is possible along southern portions of the channel and could form a storm or two, that could get quite large, to move along the channel, but it's unlikely to get into the northern half of the channel, perhaps the best chance is of it clipping the SE during Wednesday morning hours, as there's slightly weaker westerlies there, and that may allow the wind flow to push the storm more NE for it to hit the far SE. However, the steering winds below the westerlies are still more NNE orientated. Some models have the storm forming into an MCS further south right across northern France. There's a lot of variation between model outputs making it difficult to forecast tonight. If the MCS does form further south, there's also a chance that to the north of it right as it reaches the German border during the early morning hours, there's a change of wind direction to the north of it and according to the AROME, the strength of the MCS pushing through does appear to slightly angle the steering currents, perhaps due to outflow, to allow CAPE to push NNW into the far SE corner, allowing a few storms to form right in the SE in a line bending into the Benelux area. Another potential formation for storms, is the pure moisture in the northern channel may be enough to outweigh the fact that the stronger CAPE doesn't cross to the northern half of the channel, and form some storms in the northern half of the channel andor southern parts of the UK. With high moisture and low energy events, precipitation on models can tend to be weaker than expected, and with a few showers forming from the amount of moisture available (Over 30mm of PWAT all along the south coast, perhaps reaching 40mm of PWAT in areas) they could be stronger than forecast, especially into the early to mid morning as westerlies weaken along the S/SE and the steering NNE'py moving winds can push these into the south if they do form. They do risk some lightning and the lift just about supports them, but given the models don't agree much on them, it's still a low risk, and I can't imagine much lightning would come of them. Then during Wednesday late morning and early afternoon, there's an advection of a particularly buoyant air mass pushing into the SE from the Benelux area, where it combines moisture moving NE with the NW moving moisture allowing a small convergence zone into the SE, showing up on the UKV, with strong surface lift and enough energy forming for very heavy showers and lightning perhaps becoming frequent for a time with up to 1200+ J/KG of MUCAPE . It expands further west during the early afternoon but with high cap, perhaps only a few storms can form. But, that relies on the outflow from the MCS being strong enough for those to combine. The UKV is very bullish on how strong that is and with the convergence zone stalled till the evening from late morning, most models aren't that strong with them. Otherwise, Wednesday afternoon is unlikely to be that much. Though 45+ mm of PWAT pushing in even without that combination, there could be a few surprises even if the convergence zone doesnt for as some models don't actually form the convergence zone and keep it to light showers.