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New storm/convective forecast from Netweather:
http://www.netweather.tv/index.cgi?action=convective;sess=
http://www.netweather.tv/index.cgi?action=convective;sess=
Storm & Convective Forecast
Issued 2017-08-30 21:58:02
Valid: Thurs 31 Aug 2017 - 6am to Fri 01 Sept 2017 - 6am
Day 1 Convective / Storm Forecast
Synopsis
Long wave upper trough axis will slide east across the UK during Thursday. A slack cyclonic and unstable westerly flow, veering NWly across the far west, covers the UK, supporting widespread showers and scattered thunderstorms.
... IRELAND, ENGLAND, WALES and S SCOTLAND ...
Upper trough and associated cold mid-levels will create steep lapse rates across much of the UK as it slides eastwards on Thursday ... which will support the development of heavy showers and scattered thunderstorms which, with light winds aloft, will drift slowly eastwards.
Troughs in the flow may focus showers/storms into slow-moving clusters capable of producing localised minor flooding, otherwise weak vertical shear / unidirectional wind profiles should discourage an organised severe risk, though there maybe isolated instances of hail to 1 - 1.5cm given steep lapse rates and potential for strong updrafts with surface heating in late August sunshine. Also, a few funnel clouds, which may even reach the ground as a brief/weak tornado, can't be ruled out - given favourable conditions of several wind convergence zones, light winds aloft and fairly low cloud bases.