The upcoming week will remain unsettled but warmer air will attempt to make inroads but shall be greatly tempered by low pressure spreading plenty of cloud and wet weather streaming from off the Atlantic. Although I think the remainder of this month stays with the unsettled theme, the good news is models are hinting at warmer air fighting to get north in between the lows, so despite the conued cloudy, cool and wet overall pattern, at least we should begin to see periuods of warmth become more frequent, especially next week onwards.

Cool with outbreaks of rain for many next couple of days, little blast of warmth for Southeast by midweek

Monday and Tuesday will continue with the unsettled theme for many with temps ranging from 17-18C in the North to 19-21C in the South but by Wednesday, as we see the low and cold front approach the UK, SW winds excellerate the push of warmth from a very hot Iberia up into the Southern UK. Combine a strong SW flow with sunshine and I continue to believe a high of between 26-28C is possible for London.

Check out the 500mb and surface/precip chart below, notice the spike in heights over the South of England just ahead of the front and all the rain. Although I may be wrong, the model also hints of sunnier skies over the SE and if so, combined with a strong southwest wind drawing infernal heat which is over Iberia, northeastwards, it’s very possible that we see a caught-off-guard ‘very warm’ day in London.

Heavy, potentially flooding rains spread across Ireland & UK Wednesday/Thursday

By later Wednesday afternoon and evening, heavy rains spread across the UK with Scotland and northern England bearing from brunt of the heaviest, most persistent rains but all areas will see the rain which for a time will be heavy, possibly thundery. These heavy, persistent rains will impact the wettest, most flood prone areas of the UK and so further flooding is a concern over parts of the Midlands and eastern England.

Friday, Saturday and into the first part of Sunday looks to be an improving picture as high pressure builds into the UK from the southwest as the low exits.

ECMWF shows ridging and warmth Saturday/Sunday but powerhouse 980mb low forms south of Iceland, drags cold front across Scotland following summer-like day on Sunday

Heights significantly rise during Friday, Saturday and early Sunday supporting UK-wide warmth, a very mean storm system will deepen just south of Iceland with the latest ECMWF model dropping it’s central pressure to 980mb. With this intensity of low and the strength of the upper ridge to it’s south, theres a wild fightzone between the two. Lets hope this tracks well NORTH of the UK because if it doesn’t, a major storm system packing tremendous rains and gales would strike.

If this model is correct this far out, then the biggest troublemaker arrives Sunday with widepread 1-2 inch rains which could cause a lot of problrms with flooding for many given the rains which hit on Wednesday/Thursday.

The below charts show this corridor of very heavy rains forming along a boundary which seperates this deep low near Iceland with the strong high to the south. Remember, a sharp thermal contrast and or pressure gradients must be watched carefully because big precip corridors can and often form. This could be a prime example. The orientation of this boundary northwest to southeast and all this tracking due east, means that those heavy rains will spread across all of the UK during Sunday. This, if played out could be quite the flood maker given the past rains we’ve seen.

 

 

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