Behind the frontal wave / occlusion on Thursday morning, cloud breaks should allow better insolation to occur. Given cold air aloft courtesy of upper trough and steep mid-level lapse rates, 600-900 Jkg^-1 CAPE will be present provided there is sufficient post-frontal heating, with dewpoints in the 11-14C range. As a result, scattered showers and thunderstorms are expected to develop across portions of Ireland, moving NE-wards and expanding in coverage with time.

Deep convection that occurs earlier on in the afternoon will benefit from 20-30kts DLS (this generally reducing through the afternoon as the upper trough moves overhead) helping to aid some organisation, which given the degree of instability may produce hail of 2.0-2.5cm in diameter - such a risk therefore warrants the issuance of a SVR threat area, although worth stressing that perhaps only 1 (or even 0) reports of hail this size may occur. Given some reasonable cross-model agreement, and convective parameters likely in place, an upgrade to MDT may also be required across northern portions of Ireland into southern Northern Ireland - but some uncertainties exist at present over extent of cloud cover from earlier frontal wave.

Low-level convergence, perhaps along the cold front, during the afternoon hours may aid the development of scattered showers, running NE-wards with time along the front. Instability is marginal, but given falling heights aloft and reasonably-steep mid-level lapse rates in a strongly-sheared environment (30-40kts DLS) a low-end SLGT has been issued for some sporadic lightning activity.

During the evening hours, forced ascent will likely help destabilisation of the plume residing over France / BeNeLux. While the bulk of any notable thunderstorms (with prolific lightning) will remain over the nearby Continent and adjacent southern North Sea, a few thunderstorms could develop close to or over SE England and close to the coast of East Anglia - subject to some (W-E) positional errors given the spread in NWP guidance at present. This area may need revising (either expanded or removed) depending on developments during Thursday.

During the evening and night hours, an increase in deep convection coverage is expected over the Celtic Sea spreading eastwards towards SW Wales and SW England as the upper trough and associated steep mid-level lapse rates migrate east over relatively warm SSTs. 20-30kts DLS should aid in some cell organisation, and lightning coverage seems worthy of a SLGT.