PERTH — The Met Office has issued a yellow weather warning for Perth and Kinross covering what forecasters are calling a "low-level persistent damp of the soul", expected to last from Thursday morning until, in their words, "approximately March, emotionally."

"This isn't dramatic rain," explained senior forecaster Fiona Lamont at a briefing in a Scone portakabin. "It's not storm rain. There's no name for it. If it had a name, it'd be something like Derek. It's the kind of rain that doesn't fall so much as hang around in the air, waiting for you to leave the house."

The warning covers the whole region, including Perth, Kinross, Crieff, Pitlochry and Blairgowrie, where residents have been advised to expect "a fine mist that gets inside your jacket, then inside your bag, then somehow inside your sandwich."

Locals greeted the warning with weary resignation. "We've had this since 1974," said Crieff resident Andrew Scott, 77. "Every couple of years the Met Office notices and puts out a warning. Then they forget about it. The rain doesn't forget. The rain remembers everything."

Forecasters say the damp will be accompanied by a sky described as "the colour of a council meeting", temperatures "too warm for a coat but too cold for not having a coat", and a 90% chance that someone in Perth will say "it's no' that bad, really."

Emergency services have urged residents to take sensible precautions, such as wearing waterproofs, staying off the North Inch after dark, and not hanging any washing outside "at any point in the next six months, as a matter of principle."

In a rare positive note, the Met Office said there was a 4% chance of a brief sunny spell on Sunday afternoon in Auchterarder, though it warned this would last "no more than twelve minutes" and that residents should "not get attached".