Despite being on the same latitude as Moscow and northern parts of Canada, Glasgow has a significantly more moderate climate…
Glasgow benefits from a mild south-western position; the Gulf Stream currents flow up the Clyde estuary from the Atlantic warming the area. Glasgow also lies in the path of a prevailing south-westerly wind and is sheltered by the surrounding Clyde Valley hills.
All of this acts to keep the city fairly humid throughout the year. As a result, Glasgow enjoys a very stable climate with relatively warm summers and quite mild winters. The temperature in Glasgow is often milder than that in the rest of Scotland.
The spring months (March to May) are mild and cool. Many of Glasgow’s trees and plants begin to flower at this time of the year and parks and gardens are filled with beautiful spring colours.
The summer months (May to September) can vary considerably between mild and wet weather, or warm and sunny. The winds are generally westerly, due to the warm Gulf Stream. The warmest month is usually July, the daily high averaging no more than 20C. (The highest recorded temperature is 31.2C, on the 4th of August 1975.)
Despite some infrequent clear or dry days, winters in Glasgow are normally damp and cold. (The lowest recorded temperature is -17C on the 29th of December 1995). Winds and rainfall are often fairly chilling and strong, like the rest of western Scotland. Severe snowfalls melt within days and rarely lie in the city centre. December, January and February are the wettest months of the year, but can often be sunny and clear.
Glasgow is known with those who have lived there to be able to produce all 4 seasons in one day. So as a general piece of advice, make sure you are suitably equipped with clothing. And when it rains in Glasgow, there is almost always wind to accompany it – umbrellas frequently break…
The graphs below show all the major climate variables occurring in Glasgow that we have previously been asked about. All the figures combine data from the Met Office, Weather.com and Wikipedia, and are averaged over 30 years.
Average monthly temperatures (showing highs in red and lows in blue). Measurements are shown in degrees celcius.
The temperature in Glasgow follows the same pattern as almost all other cities in the northern hemisphere: temperatures are at their lowest from December to February, and then gradually increase until the summer months. In any month, you can expect temperatures between the red-blue lines. The temperature rarely varies more than this, but we do get the occasional heatwave.
Average monthly rainfall (in cm)
As any Glaswegian will tell you, Glasgow is rather wet throughout the entire year. There are two clear periods of wet and dry (or less wet) though; April to September are the dryest months, and October through to March are the wettest months. This does mean that the plants always get enough water, making Glasgow’s parks and gardens very beautiful throughout the year.
Average no. daylight hours per day, in each month of the year
The average number of daylight hours is rather variable throughout the year in Glasgow, with more than twice the number of daylight hours per day occuring in summer than in winter. A similar picture is seen throughout the UK, and the dark winters are thought to lead to the SAD (seasonal affective disorder) or ‘Winter Blues’ where people eat and sleep slightly more.
Average number of bright sunshine hours per day
The average number of bright sunshine hours follows the same pattern as the average number of daylight hours. Except that there are roughly 3-4 times less bright sunshine hours. Most of the bright sunshine occurs in the summer months. In winter, it does occasionally feel like we don’t get much of a “day”, but that just leaves more evenings and nights to enjoy!
Average number of days per month with snow still lying at 9am
The graph above shows that January gets the most snow, but only an average of 3 days actually stays on the ground without melting immediately. Despite what many people think, Glasgow does not get much snow at all. Most of the time, when it does snow in the city, the snow doesn’t lie on the ground for very long; it normally melts quickly and turns to slush. That’s when you need wellies.
Average number of days per month with gale force winds in Glasgow. (Gale force winds are those in excess of 32 miles per hour).
Glasgow is quite a windy city, and the winds can be quite strong. Gale force winds don’t often occur though. The graph above shows that in most months of the year, Glasgow gets less than 1 day with gale force winds. December and January are the middle of Glasgow’s winter, and as such are normally the windiest times. Gale force winds happen a little more frequently in these months.