Sussex weather forecast: This is how long mini-heatwave will last

The UK enjoyed blistering hot temperatures over the weekend – with highs of 33 degrees Celsius in some parts of the country. This looks set to continue at least for one more day.

The UK Health Security Agency issued a yellow heat health alert for the South East – starting at 9am on Sunday (August 11) until 9am on Tuesday (August 13). The government agency said vulnerable people in our communities ‘might struggle’ with the heat, so ‘please look out for them’.

The Met Office’s deputy chief meteorologist, Dan Holley, said on Friday: “We expect to see a relatively brief hotter and more humid spell of weather for Sunday and Monday, before these hotter conditions recede on Tuesday, allowing more unsettled conditions to return.

“This change to hotter conditions is caused, in part, by the effects of Tropical Storm Debby in North America. Debby is helping to strengthen the jet stream, causing it to meander over the Atlantic. This will allow hot air over France to move into the UK later this weekend, and early next week.

"The highest temperatures are expected in parts of central, east and southeast England, peaking on Monday with maxima over 30°C widely and possibly 33-34°C in some places. This will be accompanied by some high night-time temperatures and humidity, especially on Sunday night in southern and western areas.”

The Met Office warned that pollen and ultraviolet levels ‘will increase as we see temperatures rise’. The hottest time of the day will be between 1 and 3pm.

A large part of the UK is covered by a yellow warning for thunderstorms between 2am and 1pm today. This includes Leeds, Newcastle, York and the whole of Scotland – but excludes the south of England.

Mr Holley added: “Along with the rise in temperatures, there is also an increasing threat of heavy rain and thunderstorms on Sunday night and into Monday. This looks most likely across portions of Wales, northern England, Northern Ireland and southern and eastern Scotland, but the advice is to keep up to date with the latest forecast and any warnings by checking our website or app.

"Although the southeast may still cling on to some heat on Tuesday, the hot air mass will likely become displaced by fresher conditions. Things then look to become unsettled once again, with occasional Atlantic frontal systems or showers moving through at times. Between these systems though, there will be sunshine on offer, with temperatures returning closer to average.”