[Tony Gilbert]

7.45pm Mon

Slight Risk of Thunderstorms Central east Ireland, and all central UK regions 12Z-19Z

A more promising outlook for results with further surface troughing developing during the afternoon period within a continued NWsterly airstream and strong PVA aloft. A strong upper jet stream looks to be orientated across Ireland and SWestern regions of the UK. ATM there would seem to be some overlap of instability to stronger shear potential. Whilst low level shear is likely to be rather weak and straight lined, the mid level support available as per yellow box could develop the odd isolated stronger thunderstorm with the potential for large hail. Freezing level looks to drop well below cloud base by early afternoon for this sector. In fact the upper long wave trough is significantly deep and will develop numerous cumulonimbus cloud anywhere across the UK.

Certainly one to keep an eye on!

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[Tony Gilbert]

UPDATE 8.45am

As per earlier forecast with UK risk box extended into E.Anglia

[Tony Gilbert]

UPDATE and RESULTS 6.58pm

Notts 12Z sounding not available today though some detail regarding conditions at play based on Valentia and Camborne show a impenetrable inversion at 650mb which pretty much capped off vertical ascent of any updraft. Ironically just above this level at 500mb is the base level of the jet stream. Hence storms only remained marginally sheared today as they were unable to lift into the sheared zone and utilise this upper support.

PS. I have nevertheless noted at least two lowerings which partially resembled wall clouds on nearby convective bases. ...In short if it were not for the hard mid level inversion, today could well have rendered some very distinct storm activity!!

This post has been edited by Tony Gilbert: 15 May 2012 - 18:09

[Bazmundo]

Larkhill did an ascent at 10z if that helps, attached with an estimated surface temp of 8C yielding some 70J/Kg CAPE (not great lol).

From here (latest data loads when red dots clicked, interactive parcel temp on skew-T, and RAOBs archive and GFS soundings from "Load Soundings" button):
http://www.btinterne...dingsFramed.htm

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[Tony Gilbert]

Bazmundo, on 15 May 2012 - 22:17, said:

Larkhill did an ascent at 10z if that helps, attached with an estimated surface temp of 8C yielding some 70J/Kg CAPE (not great lol).

From here (latest data loads when red dots clicked, interactive parcel temp on skew-T, and RAOBs archive and GFS soundings from "Load Soundings" button):
http://www.btinterne...dingsFramed.htm

OK thanks for that Glyn. This would be fairly representative of the conditions;- Solid inversion above 650mb and CAPE up to this level. We can see that the stronger winds occurred within the inversion sector!