UK heatwave comes to explosive end… next up… cool, wet & windy low pressure

Written by on July 28, 2018 in Rest of Europe, United Kingdom & Ireland with 0 Comments

In true heat wave breaking style, powerful thunderstorms packing flooding rain, damaging wind, large hail and frequent lightning became widespread yesterday as cooling Atlantic fronts slammed into our hot, humid atmosphere.

Credit: BBC Weather

Ahead of the approaching system, temperatures both at the surface and at 5,000ft climbed 10-15C above normal across central, southern and eastern England but 30C temperatures were achieved all the way to Scotland’s Moray coast.

Yesterday’s highs

Credit: Meteoceil

Credit: The Weather Network

Surface chart

Credit: Tropical Tidbits

850mb temperature anomaly

Credit: Tropical Tidbits

Strongest storms from Kent to Yorkshire? Here is where cooler air crossed over the warmest low level air and so the lapse rate and CAPE was highest (greatest instability).

Credit: Tropical Tidbits

As the heat humidity gave way to a blow up of thunderstorms, many parts of southern and eastern England saw 10-15C temperature drops within a couple of hours with streets turning to rivers as the rains couldn’t come quick enough.

Credit: UK Weather Information

These rains arrived after Brooms Barn, Suffolk observed 51 consecutive days without rain, said to be the longest stretch for any UK site this year.

Credit: express.co.uk

This surpasses the streak of 45 days back in the heatwave of 1976. According to the Met Office, the UK record for longest spell without rain is 60 days set back in 1893.

With air cooling over warming in response to an incoming front (enhancing lift), CAPE values went through the roof up the east side of the Pennines. The MO correctly issued an AMBER warning for the thunderstorms.

Met Office

The storms put on quite the show.

Over NE England (Credit: Peter Gibbs)

Headingley, Leeds (Credit: Johnny Orbell)

Flooding rains, damaging wind, large hail and frequent cloud to ground lightning have been common over the last 36 hours.

Credit: BBC Weather

Thursday was the hottest day of the current hot spell and of 2018 so far!

Credit: BBC Weather

Credit: BBC Weather

A look at this past week’s 5-day stretch of 30+.

Monday: 33.3C at Santon Downham

Tuesday: 31.4C at Cavendish

Wednesday: 32.0C at Wisley

Thursday: 35.1C at Wisley

Friday: 34.7C at Tibenham

Last Sunday failed to make 30C by a mere 0.2C.

We’ve now tallied 20 days at or above 30C this summer so far and we’re unlikely to be done yet despite the sharp turn to cooler.

As persistently warm as it’s been, this summer’s maximum temperatures still fall short of 2015.

Credit: BBC Weather

With windier weather (causing mixing) comes a drop in SST and cooler, deeper waters rise to the surface.

Ahead of these rains.

Saying goodbye to our Mediterranean pattern and saying hello again to our beloved UK pattern following it’s near 2 month holiday!

We’ve not one but two lows.

Credit: Tropical Tidbits

Credit: Tropical Tidbits

Credit: Tropical Tidbits

The fresher air was noticeable today.

Credit: Tropical Tidbits

That fresher feed holds on through early next week before more heat and humidity builds later next week and by the weekend.

Credit: Tropical Tidbits

It’s possible that we could see the return of 30+ by this time next weekend.

Credit: Tropical Tidbits

It’s a long way out but the models are sniffing at more extreme heat in about 10 days from now.

Credit: Tropical Tidbits

Tags: , , ,

Follow us

Connect with Mark Vogan on social media to get notified about new posts and for the latest weather updates.

Subscribe via RSS Feed Connect on YouTube

Leave a Reply

Top