In spite of its northerly latitude, and being close to the same line as Moscow and Copenhagen, Paisley's climate is classified as 'Oceanic'. Weather data is collected from three official weather stations - Paisley (Obersvatory), Abbotsinch (Glasgow Airport) and Bishopton (north of Paisley). The City of Glasgow's weather readings are based on those from Glasgow Airport, 1 1/2 miles north of Paisley town centre. Paisley Observatory is the nearest to the town centre, located on the hill behind the High Street called Oakshaws.
Owing to its westerly position and proximity to the Atlantic Ocean, Paisley is one of Scotland's milder areas. Temperatures are usually higher than most places of equal latitude away from the UK, due to the warming influence of the Gulf Stream. The downside of this is that Paisley doesn't get distinct seasons like many other Western European cities.
Winters are cold and overcast, with a January mean of 4.0°c (39.2°f), though lows sometimes fall below freezing. Since 2000 Glasgow has experienced few very cold, snowy and harsh winters where temperatures have fallen much below freezing. The most extreme instances have however seen temperatures around -12°c (10°f) in the area. Snowfall resulting in snow lying on the ground is an infrequent occurrence and generally short-lived. The spring months (March to May) are usually mild and often quite pleasant. Many of Paisley's trees and plants begin to flower at this time of the year and parks and gardens are filled with spring colours.
During the summer months (June to August) the weather can vary considerably from day to day ranging from relatively cool and wet to quite warm with the odd sunny day. Long dry spells of warm weather are generally very scarce. Overcast and humid conditions without rain are frequent. Generally the weather pattern is quite unsettled and erratic during these months, with only occasional heatwaves.
The last few summers have seen below average temperatures, sunshine hours and also above average rainfall. This has been attributed to by the position of the jet stream which has moved from its more northerly route to the north of Scotland to a more southerly direction which has caused low pressure systems to circulate and develop to the South and West of the UK. This has blocked the warm continental high pressures developing across the country and moving upwards from the south.
The warmest month is usually July, with average highs above 19°c (66°f). Autumns are generally cool to mild with increasing precipitation. During early autumn there can be some settled periods of weather and it can feel pleasant with mild temperatures and some sunny days.
The British have a love affair with the weather, and is often used to 'break the ice' with a stranger.