Temperatures in Northern Ireland breach 28C - and are set to do so again this week

What counts as a ‘heatwave’ varies across the UK, but in Northern Ireland it is classed as a run of three days when temperatures have reached or exceeded 25C.

In fact, it looks like Northern Ireland is going to get four.

The first day to hit 25C-plus was Monday, when 25.3C was recorded in Castlederg.

Then today, a high of 28.1C was recorded at Katesbridge in Co Down at 2.43pm, making it NI’s hottest spot of the day.

Meanwhile temperatures of 27.3C were recorded today in Derrylin, Fermanagh, and Glenanne, Co Armagh, at 2.58pm and 1.57pm respectively, while the next hottest reading was 27.1C at Aldergrove at 3.40pm.

Then tomorrow and Thursday are expected to surpass the 25C mark at a number of locations in the Province, with Thursday being particularly hot (see below).

None of this will trouble the record books however; the all-time top temperature for June in the Province is June 30, 1976, when Knockarevan in Fermanagh hit 30.8C.

And the all-time high, full stop, is 31.3C, recorded in Castlederg on July 21, 2021.

SHAPE OF WEEK AHEAD:

In Armagh City (where it was 27C today), the Met Office is forecasting some cloud tomorrow and temperatures up to 25C, followed by a cloudless Thursday with temperatures up to 29C, before some clouds make a return on Friday and temperatures dip to 24C.

In Enniskillen (temperatures of 25C today), it is forecasting some cloud tomorrow and temperatures of 25C, with less cloud on Thursday and temperatures hitting 29C, before the clouds return on Friday and temperatures dip to 23C – with some showers also predicted.

In Belfast (27C today), temperatures are set to be relatively restrained tomorrow with a high of 22C and some cloud, before thermometers leap up to 28C on a cloudless Thursday, then fall to 26C on Friday as the clouds return.

Castlederg (23C today) is set to be a mix of sunny and cloudy between tmorrow and Friday, with highs tomorrow of 24C, followed by 27C on Thursday, then down to 21C on Friday with the potential for rain.

In Coleraine (where it was 24C today), is expected to bring temperatures of 20C plus some cloud tomorrow, followed by pure blue skies on Thursday and readings of 27C, and then a cloudy Friday and a high of 19C.

Katesbridge in the south of Co Down (which saw readings of 27C today), a village so often associated with weather extremes, is due to experience sun with some clouds tomorrow and a high of 23C, followed by clear skies and a top reading of 27C on Thursday, before temperatures dip back down to 25C on Friday as some clouds creep back in.

Met Office forecaster Honor Criswick told the News Letter that, come the weekend in NI, “it looks like we’re just starting to see things break down” with Saturday quite cloudy with showers and a high of around 21C, and a similar position on Sunday.

GB HOTTER BY A COUNTRY MILE:

However, Northern Ireland’s temperatures pale in comparison to what has already been recorded in GB – and what is set to come.

On Monday, the hottest temperature in GB was 32.5C in Yeovilton, Somerset.

Today, the high was 35.6C in Wisley, in Surrey, while an amber alert for heat was in force across southern England and Wales.

This is replaced by a rare red alert in the region both tomorrow and Thursday

Hundreds of schools in GB will fully or partially close over the next few days because of the extreme heat, with temperatures set to hit record highs.

A “heat-dome” over western Europe could bring temperatures of nearly 40C tomorrow with this latest heatwave expected to surpass the record for June of 35.6C set in Hampshire in 1976.

The temperature could come close to the UK’s all-time high of 40.3C which was measured in July 2022.

Met Office spokesman Grahame Madge said: “The Met Office is flagging 39C as a headline maximum temperature on Thursday, most likely for somewhere in London or the South East.

“It is possible we could see temperatures higher than the 39C if the final values are at the upper end of our narrow range.

“It is important to remember that the temperature value is only one element of this extreme heatwave story.

“The other major factor is the high humidity which for many will make the intense heat even harder to endure.”

In a post on X this afternoon, the Met Office said: “Last night, parts of England and Wales didn’t drop below 20C.”

Children at some schools in England have been told they can wear PE kit rather than full school uniform in the days ahead.

The hot weather led to thunderstorms and lightning strikes over England during the early hours of today.

The Met Office said this morning that Somerset had “around 18,540 strikes in the past 24 hours”.

The London Fire Brigade received 400 calls overnight from Monday to Tuesday, including two house fires believed to be caused by lightning strikes.

There was also severe disruption across London’s transport network during this morning after heavy rain caused flooding.

Fredi Otto, professor of climate science at Imperial College London, said: “Temperatures above 35C used to be extremely rare in the UK.

“They have now occurred in seven out of the last 12 years, and this sustained surge in extreme heat would not have happened without human-caused climate change.”

NI Water tonight urged the public to “respect a strict ban on barbecues, open fires and water-based activities at all its sites”.

It follows significant wildfire damage at Silent Valley earlier this year, and recent reports of people entering various reservoirs.