Glasgow is set to be the warmest place in Scotland on Tuesday, September 29, with temperatures reaching 18C during the afternoon, according to the Met Office. The mercury will stay at 17C through the evening.
The unseasonal warm spell will see temperatures climb several degrees above the usual average for this time of year. The Met Office's 1991-2020 climate averages put Scotland's average maximum temperature for September at 14.78C.
Warmth across the country
Other parts of Scotland will also see temperatures rise, with highs of 17C forecast in Fort William, Edinburgh, Dumfries and Ullapool. Dundee and Aberdeen are expected to reach 15C.
The warmer conditions are being driven by low pressure in the Atlantic, which will help pull warmer air across much of the country before conditions turn increasingly wet and windy.
Forecast details
The Met Office said Tuesday will start widely cloudy, but temperatures will rise noticeably as sunshine develops during the afternoon. Met Office Chief Forecaster Matthew Lehnert said: "A deep area of low pressure far into the Atlantic is the primary driver behind the UK’s weather over the next few days."
"Its first influence will help pull some warmer air over much of the country on Tuesday, with a peak of 27°C likely – which is notably warm for the time of year," he added. "A warm night will follow across southern and eastern areas, with minimum temperatures of 19°C in places."
While Scotland is not expected to reach the 27C UK-wide peak, the 18C forecast for Glasgow would still be several degrees above the country's average September maximum.
Rain and wind to follow
The warmer conditions will not last, with western parts of the UK expected to become increasingly wet and windy by Tuesday evening. A weather front will gradually move from west to east late on Tuesday and through Wednesday, bringing rain and stronger winds to parts of Scotland.
Met Office Deputy Chief Forecaster Steven Keates said: "As this weather front moves gradually from west to east late on Tuesday and Wednesday, many places will see around 10mm of rain, with in excess of 40mm possible in some isolated spots in south-facing hills in the west."
"This period of weather will also see gusty winds, with gusts over 50mph possible, particularly on exposed coasts in the northwest. Large waves are likely to affect some coasts in the west, coinciding with high spring tides," he added.
Thursday and Friday are expected to bring further rain or showers to many areas of Scotland, some of which could be heavy. However, according to the Met Office, there should also be some drier and brighter spells.
The outlook is expected to improve over the weekend as high pressure gradually builds across much of Scotland. This should reduce the chance of rainfall and bring more pleasant conditions to many areas, with some sunshine and lighter showers increasingly confined to the far northwest.
