The UK could be set for the hottest day of the year for the second day in a row in the run up to a weekend filled with blazingsunshine and scorching temperatures. However, the balmy weather comes with a caveat as the UK may be facing "intense thunderstorms" by week's end, according to recent predictions.

In many parts of the UK today, and over the coming daystemperatures are expected to exceed 30C. The reason for the warmer temperatures is due to a "combination of several factors", according to Tony Wisson, Deputy Chief Meteorologist for the Met Office.

A number of areas in the UK have been issued with a heat-health alert warning. The alert affects all regions in England and will be in place from 12pm on Thursday June 19, until 9am on Monday, June 23.

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This precautionary system activates to alert citizens about potential health risks due to extreme temperatures.

Brits are advised to brace for "uncomfortable heat" that will last all day and linger through the night. Forecasts suggest "tropical nights" could occur, with night-time temperatures stubbornly staying above 20C, potentially disrupting sleep patterns, reports the Liverpool Echo.

Dan Holley, Deputy Chief Meteorologist for the Met Office, predicts: "The highest temperatures from this hot spell are forecast for Saturday, with low 30s Celsius expected widely across England, and even hitting up to 34°C in certain eastern localities.

"Despite this, the more uncomfortable heat will be in northern and western areas initially, where despite somewhat lower temperatures the air will be more humid.

"While Saturday will be a dry and fine day for many, a few showers or thunderstorms will be possible across northern and western parts of the UK, with an increasing risk of some intense thunderstorms developing across portions of north Wales, northern England and southern Scotland later in the afternoon and into the evening hours, which could bring heavy downpours, frequent lightning, gusty winds and possibly large hail.

"The nights will also be quite warm, with the possibility of temperatures not falling below 20°C in some areas, making it hard to sleep. This is what we term a 'tropical night'.

"Temperatures will ease from the west on Sunday as fresher air arrives from the Atlantic, although parts of East Anglia and the far southeast of England could still see 28-29°C for a time."

From Saturday to Sunday, Glasgow will see temperatures plunge from 27C to 19C, Plymouth's from 24C to 21C and Liverpool's from 28C to 22C.

Further east, Brits will see sizzling temps for another day, with highs of 28C in London, which will drop to 23C on Monday, and plunge from 28C to 23C in Kent, The Express reports.

Heatwave conditions in the UK are met when a location records a period of at least three consecutive days with temperature values meeting or exceeding the heatwave temperature threshold for that location. Across much of the north and west of the UK, this threshold is 25°C, but across Greater London and the Home Counties, the threshold is higher, at 28°C.

The high pressure is anticipated to shift away from the UK early next week, leading to a drop in temperatures. However, the Met Office has expressed uncertainty over how swiftly this will occur and what the peak temperatures across the UK will be.

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