January and February are the coldest months with an average of around 5 to 7 °C. The summermonths have an average of about 19 Degr. C. The annual mean temperature on Ben Nevis (1344m) is -0,3C. Snowfall occurs on less than 20 days near the west-coast to more than 100 days in the Cairngorm Mountains mainly in the months December to March.
Weather Records, Extremes and other interesting bits
Maximum duration in a month: 329 hours at Tiree (Argyll and Bute) in May 1946 and May 1975.
Minimum duration in a month: 0.6 hours at Cape Wrath (Highland) in January 1983.
From the ten wettest counties in the UK, six of them are in Scotland - Argyllshire 2200mm, Dunbartonshire 2000mm, Inverness 1970mm, Ross and Cromarty 1800mm, Buteshire 1720mm and Kirkcudbrightshire 1630mm. The other three counties are in Wales and one in Cumbria.
Maximum in a day (09-09 UTC): 238 mm at Sloy Main Adit, Loch Lomond on 17 January 1974.
Highest gust recorded at a low-level site: 123 knots (142 mph) at Fraserburgh (Aberdeenshire) on 13 Feb 1989.
Highest gust recorded at a high-level site: 150 knots (173 mph) at Cairngorm Automatic Weather Station (on the border of Highland and Moray at an altitude of 1245 m AMSL) on 20 March 1986.
Highest recorded 32.9 °C at Greycrook (Scottish Borders) on 9 August 2003.
Lowest recorded -27.2 °C at Braemar (Aberdeenshire) on 11 February 1895 and 10 January 1982.