[Tony Gilbert]

2pm Sun

Slight Risk of Isolated Convective Showers with Hail 10Z-16Z

A low risk outlook posted as an item of interest.

Weak low pressure system west of UK looks to develop an occlusion just to the east of the UK through Monday. Some signs of weak troughing further west possible where stronger lapse rates could trigger the odd isolated hail shower for a time. GFS currently forecasts around 160 J/kg of elevated CAPE along a narrow swathe from N.Wales through to central southern UK regions. The most significant influencing factor will be localised insolation. Though, whilst weak may increase height falls sufficiently to produce isolated pockets of convection for a time. Freezing level certainly low enough to produce very localised down pours of small hail. Cloud tops expected to reach 500mb where there may be some scope for more organised convection as per (yellow box). Expect some good scenic anvils for the said region.

Currently the UKMO, together with other models makes no recognition for this trough. Though currently GFS does!

All in all LCL and LFC looks too elevated to create any significant results. Hail looks to become the main factor here!

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This post has been edited by Tony Gilbert: 04 March 2012 - 14:26

[Tony Gilbert]

UPDATE 8.50am Mon

Both GFS and NMM step back further limiting instability.
Remains a rather marginal outlook indeed!