The fourth heatwave of the summer is set to hit the UK in the next few days following a weekend of cooler temperatures.
Following a smattering of rain for many on Sunday, the heat is expected to spike again in the south.
Parts of southern England will again meet their heatwave criteria on Wednesday, with highs of 32C or 33C expected.
Other areas will reach the threshold on Thursday.
Forecasters are expecting this week’s heat to be a “north-south split”, with clouds and outbreaks of rain continuing in Northern Ireland, Scotland and northern England.
The heatwave should be short-lived, with temperatures widely cooling to close to average by the weekend, said Met Office senior operational meteorologist Dan Stroud.
July was 3C above average across the UK, according to provisional Met Office data.
This could put it among the hottest three or four months of July on record, said Mr Stroud.
Southern England has had just 1 per cent of its average July rainfall. England has had 5 per cent and the UK as a whole 20 per cent, according to the Met Office.
Mr Stroud said: “In terms of wildfire, obviously the continuation of the dry and hot conditions does elevate the fire risk.
“That rain we’ve had, even though it’s welcome rain for the last last few hours, is certainly not enough really to do a huge amount for the dry conditions we’ve already already got. That risk continues.”
If they start, fires are likely to become exceptionally severe on Sunday in pockets of east, south-east and the south of England, according to Met Office data used by Natural England and Natural Resources Wales.
That “exceptionally severe” risk level disappears for the whole country before returning on Wednesday for a wider breadth of east, south, and south-east England.
It then focuses in the east and south-east of England on Thursday.
The Fire Severity Index looks at data including rainfall, temperature and humidity.
Agencies use it to assess the severity of fire if it starts. It does not cover the chances of wildfires occurring.
Emergency crews have already spent days fighting large wildfires in Wales and Scotland that forced people to evacuate their homes.
Mr Stroud emphasised that the Fire Severity Index measures humidity and drier weather increases the fire risk.
The second heatwave was particularly humid and that “does reduce the risk somewhat”.
The latest heatwave has been drier and longer-lasting and humidity levels are expected to fall as the fourth heatwave arrives.
