Met Office warning for Wales with freak heat up to 27C persisting through night

North Wales Live

11-07-2025

This weekend's 'uncomfortably' hot weather may be followed by more heatwaves this month, weather models suggest. The dry spell is worrying water companies, with Dŵr Cymru pleading with people in Wales to use water sparingly.
The Met Office is warning of scorching weather in Wales on Saturday, July 12. Temperatures are predicted to peak at 32C in Wrexham and Denbighshire, and 33C in Monmouthshire, though it will be balmy everywhere.
Even more dramatic are night time temperature forecasts. By midnight on Saturday, some north eastern areas of Wales could still be sweltering in the high 20Cs - potentially up to 27C, according to the GFS model. Cheshire could see highs of 29C during the night.
The Met Office said: 'The heat will persist into Saturday night, particularly in western and north-western parts of the UK. Overnight temperatures are expected to remain above 20°C in some areas, making for an uncomfortably warm night and potentially disrupting sleep.'
Outlier forecasts were modelling another hot spell next weekend (July 19-20), with dramatic temperature peaks higher even than the coming days. However these have since been scaled back, especially in Wales – though it could remain very warm in southern and eastern England, with the heat perhaps spreading as far as east Wales.
Instead, all eyes are now on late July, with Scandinavian blocking in place and the possible return of an Azores high. Netweather meteorologist Ian Simpson said there is potential for 'exceptional heat' around the last weekend in July – though probably only briefly and mainly centred on eastern England.
With France predicted to be 'especially hot' that week, he said it will 'leave Britain quite prone to the occasional burst of notable heat.... should we pick up a southerly flow pulling in this hot air'. Join the North Wales Live Whatsapp community now
Some more excitable online forecasters have raised the spectre of 1976, drawing comparisons with an iconic summer that was the hottest in over 350 years and the driest in 200 years. Yet the heat has been different this year.
Although June 2025 was the warmest ever recorded in England, and the third warmest in Wales, summer 1976 was characterised the longevity of its hot spell, with multiple locations recording heatwave conditions lasting more than two weeks. Moreover, the heat subsided only gradually.
Although Britain is now in its third official heatwave, this is not expected to last more than four days, with cooler conditions expected from Monday (or Tuesday further east).
Warmer weather is predicted to build from mid week, peaking next weekend before tailing off again. A similar pattern is currently forecast for the following week, with another burst of heat in parts of the UK, followed again by a dip.
In its long-range forecast, the Met Office said: 'Around the turn of the month, there is a signal for perhaps more widely unsettled weather to develop, though the details of this remain uncertain.'
The conditions are adding to pressures at Dŵr Cymru, which is expecting up to a 20% increase in demand for water across its network between Friday and Sunday. It suspects more showering, drinking, filling up pools and using sprinklers.
Following the driest Spring on record, and with falling reservoir levels, the company announced 'Developing Drought' status for Mid and South Ceredigion along with parts of Carmarthenshire and Pembrokeshire.
Although there are no other areas of concern now, the company is urging people to not be complacent with the supplies available. To keep up with demand, Dŵr Cymru tankers are moving around the network to replenish underground drinking water tanks. Engineers are working flay out to fix leaks (700 per week).
Ian Christie, managing director of Water Services, urged everyone to moderate their water use – especially those with garden sprinklers. 'While we will do all that we can, we're asking customers to help their communities by playing their part to avoid wasting water, saving it wherever possible,' he said.
'Garden sprinklers, for example, are one of the biggest consumers of water in the garden as they use on average 1,000 litres of water every hour. This is the equivalent of what a typical family would use inside the house in two days.'
The company is also warning people not to swim in unauthorised reservoirs during the warm weather.