Convective Outlook: Fri 07 Aug 2020
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Convective Outlook

VALID 06:00 UTC Fri 07 Aug 2020 - 05:59 UTC Sat 08 Aug 2020

ISSUED 09:35 UTC Fri 07 Aug 2020


An upper trough will slowly advance from the Atlantic, drawing two plumes of high Theta-W northwards across the British Isles on Friday. One narrow tongue will exist ahead of a surface cold front that will migrate gradually eastwards across Ireland and western Scotland. Subtle impulses aloft could develop some elevated convection within this zone that may be capable of producing a few lightning strikes - however, model guidance varies over timing and placement for any such activity. Current thinking is most likely location for some sporadic lightning is E / NE Ireland mid-afternoon drifting towards SW Scotland.

Meanwhile, a plume of very steep mid-level lapse rates will expand northwards across England and Wales through the day. Very hot, dry low-level air will generally serve as a cap to surface-based convection, however some subtle cooling and moistening of the mid-levels (particularly 500-650mb) seems likely as subtle impulses / PVA lobes track northeastwards during the afternoon and evening hours. These may aid in the development of elevated showers, although much of the precipitation evaporating before reaching the ground. A few isolated lightning strikes are not entirely ruled out from these high-based showers, which may persist overnight across East Anglia / SE England.