Motorists are on high alert as the mercury rises, with a warning that scorching temperatures could lead to an unexpected £180 expense.

Experts at Prestone, specialists in vehicle maintenance fluids, have issued a stark warning about the potential for severe windscreen damage due to the UK's impending heatwave.

A spokesperson for Prestone said: "Slightly counterintuitively, it isn't the heat directly that causes damage, it is the fluctuation in temperature that could cause damage. Mechanical tension is placed on an object when parts of it are being expanded due to heat and some are contracting due to being cooled down."

They elaborated on the phenomenon known as thermal shock, stating: "When this happens to brittle materials such as glass, it can cause them to explode or crack; this is called thermal shock. To stop your windscreen from accumulating a lot of heat, avoid parking in direct sunlight. Consider parking under a tree, in a garage or other forms of shade."

The experts also highlighted the importance of maintaining a pristine windscreen to prevent weather-related damage.

Speaking to Birmingham Live, they advised: "A windscreen in good condition is less likely to be affected by changing temperatures. Regularly washing your windscreen and checking for chips or cracks will allow you to fix the small issues before they require a full windscreen replacement."

The UK is bracing for a heatwave with temperatures set to soar this week, reaching their peak by Thursday. The Met Office has shed light on the situation: "Earlier low cloud has lifted to leave a largely dry and settled day with bright or sunny spells for many. Some areas of low cloud and patchy drizzle will persist around southwestern coasts, and the northwest will be cloudier with patchy rain. It will feel very warm in places, with maximum temperatures of 28C in London and mid-20s across the eastern half of the UK."

As Glastonbury Festival kicks off on Wednesday, festival-goers heading to Worthy Farm in Pilton, Somerset, are in for "mostly warm, dry and settled" conditions over the five-day extravaganza. Despite this, the Met Office cautions that there's a chance of scattered showers from the get-go, which could linger throughout the weekend.

Glastonbury attendees have been advised by the Met Office to expect a "largely dry and cloudy" weekend, although they should be prepared for possible showers.

Met Office spokesperson Andrea Bishop commented: "From Friday to Sunday it will remain largely dry and cloudy, with the potential for lighter showers across the weekend. Conditions will be slightly above average between 18C and 21C."