The Met Office has announced that the threshold for a heatwave will most likely be met or exceeded across England and Wales. The warmest parts of the UK could get close to 34C on Thursday.
However, it is unlikely that they will beat the record for the hottest day in June ever which was 35.6C in Southampton in 1976.
The upcoming heatwave has caused the Met Office to warn of a level two heat alert for most of England.
During the day, temperatures are forecast to exceed 30C and at night are expected to reach 15C or above in central, southern and eastern England.
Met Office Chief Meteorologist, Dan Suri said: “Northern Ireland and Scotland will be under a band of cloud and rain on Monday and Tuesday, however it’ll be dry elsewhere with plenty of warm sunshine and temperatures reaching 28 or 29 Celsius in a few spots on Tuesday.
“Temperatures will continue to climb through the week with a hot spell developing across much of England and Wales.
“From Wednesday temperatures will widely reach into the high twenties Celsius and it’ll be hot across much of the UK, especially central and southern England where we could see highs of 30 to 34 Celsius.
“This hot weather is expected to last until at least Friday and so heatwave conditions are likely to develop for some areas this week.”
According to the Met Office, a heatwave is an extended period of hot weather which is higher than expected for that time of the year and can also be accompanied by high humidity.
A heatwave threshold is achieved when the daily maximum temperatures are met or exceeded for three consecutive days.
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Warnings are usually sent to health and social care workers so that they can take the appropriate measures to protect people’s health.
The Met Office released a yellow alert.
This is usually triggered when the likelihood of reaching threshold temperatures in as least one region for two days or more is at a 60% chance.
On Tuesday, the risk was recorded as an 80% chance between 9am on Wednesday and 9pm on Friday.
This week, England and Wales have experienced mostly dry, sunny and warm conditions.
Whereas Ireland, Northern Ireland, and Scotland have seen cold and rainy weather.
However, on Wednesday, these areas will experience similar weather to England and Wales but not as warm.
This means the risk of a heatwave will be lower in Ireland, Northern Ireland and Scotland.
On Friday, thunderstorms are expected in certain regions.
Torrential downpours, rain, hail and frequent lightening are also reportedly a risk towards the end of the week.
From Saturday, cooler temperatures are expected after the heatwave.