Scotland has recorded the hottest day of the year so far, with Threave in Dumfries and Galloway reaching 30.1C.
The Met Office confirmed that the country is now officially experiencing a heat wave after a long spell of hot weather.
A number of weather stations across the country have hit 25C or higher for three days in a row.
Scotland’s previous warmest day of 2023 was recorded on Saturday in Auchincruive, South Ayrshire.
The mercury reached 29.8C and the warm weather will continue for the next week.
Hot spots across the country include Eskdalemuir in Dumfries and Galloway and Aviemore.
As people enjoyed the rising temperatures, firefighters have warned of an increased risk of wildfires.
On Saturday, firefighters tackled a wildfire that broke out south of Inverness in the Daviot area, with local residents advised to keep windows and doors closed because of the smoke.
The blaze was about 30 miles from Cannich – the site of another recent wildfire believed to be the largest on record in the UK.
The Met Office predicts that next week the risk of thunderstorms will continue in some areas and temperatures are likely to remain above average.
It has extended the yellow warning for thunderstorms in the Highlands and west of Scotland until 9pm Tuesday.
The railway south of Inverness has been closed as a precaution as engineers deal with flooding in the area.
Network Rail Scotland said the line must be inspected at Tomatin before it can be opened to trains.
Sepa has also warned of significant water scarcity in the Loch Maree area of the Highlands, and moderate water scarcity in Ness in the Highlands and Esk in Dumfriesshire.
Auchincruive was the only place in Scotland on Sunday to meet technical heat wave conditions.
However, the Met Office does not confirm heat waves based on individual stations.
Threshold temperatures must be recorded in a greater number of weather stations to be considered a heat wave.
And on Monday, a number of weather stations passed the three-day mark at 25C or higher.
Cooler temperatures have been recorded in northern Scotland.
Tourists from relatively warmer countries have called the hot period “very pleasant”.
Lisa Merrifield and her family visit Scotland on vacation from their home in San Antonio, Texas.
“A heat wave for us is above 100F (37C) for several days,” she said.
“This is bearable, it was very pleasant when we were here.”
“We would trade this for our summer,” added Derek Charette. “It’s hot every day.”
New Zealand’s Sam Kidner and Naomi Brown said the Scottish heat wave was much more humid than a New Zealand heat wave.
“It’s not terribly hot compared to what we’re used to,” said Naomi.
“It’s definitely more humid,” Sam said. “It’s hot, so we sweat a little here.
“I’m looking forward to the rain. A heat wave is a bit less humid for us, so it’s definitely more comfortable.”
What is a heat wave?
A heat wave is a prolonged period of warm weather that exceeds the expected conditions of the area at that time of year.
In the UK, a location must record daily maximum temperatures that meet or exceed the heat wave temperature threshold for that time of year on at least three consecutive days.
Heat waves are extreme weather events, but research shows that climate change is making these events more likely.
It is not possible for meteorologists to link individual weather conditions, such as the current heat wave, to climate change.
But experts have no doubt that climate change is causing global temperatures to rise.
Britain has been slowly warming since the 19th century. Over the past three decades, the UK has warmed by 0.9C.
The 10 warmest years since 1884 have all been since 2002. And none of the coldest years have been recorded this century.
Scotland experienced two heat waves last year – in July and August.
In mid-July last year, the country experienced its highest ever temperature of 34.8°C in Charterhall. This broke the previous record of 32.9 °C during the 2003 European heat wave.