Climate in United Kingdom

The UK is well known for the variability of its weather but is generally temperate – from day to day, season to season, year to year and place to place. Favourable weather conditions usually occur more often in the spring and summer. Its position in the mid-latitude westerly wind belt on the edge of the Atlantic Ocean with its relatively warm waters, yet close to the continental influences of mainland Europe, plays a major role in this.

The prevailing winds are southwesterly, from the North Atlantic Current. More than 50% of the days are overcast. There are few natural hazards, although there can be strong winds and floods, especially in winter.

Rainfall

Average annual rainfall varies from over 3,000 mm in the Scottish Highlands down to 553 mm in Cambridge. The county of Essex is one of the driest in the UK, with an average annual rainfall of around 600 mm, although it typically rains on over 100 days per year. In some years rainfall in Essex can be below 450 mm.

Geography climate conditions

The principal factors that influence the country's climate include its northerly latitude (which ranges from 50° to 60° N), the close proximity to the Atlantic Ocean, and the warming of the surrounding waters by the Gulf Stream. The weather can be notoriously changeable from one day to the next but temperature variations throughout the year are relatively small.

The boundary of convergence between the warm tropical air and the cold polar air lies over the United Kingdom. In this area, the large temperature variation creates instability and this is a major factor that influences the notoriously changeable and often unsettled weather the country experiences, where many types of weather can be experienced in a single day.

Regional Climate

Regional climates in the United Kingdom are influenced by the Atlantic Ocean and latitude. Northern Ireland, Wales and western parts of England and Scotland, being closest to the Atlantic, are generally the mildest, wettest and windiest regions of the UK, and temperature ranges here are seldom extreme. Eastern areas are drier, cooler, less windy and also experience the greatest daily and seasonal temperature variations. Northern areas are generally cooler, wetter and have a smaller temperature range than southern areas.

Though the UK is mostly under the influence of the maritime tropical air mass from the south-west, different regions are more susceptible than others when different air masses affect the country: Northern Ireland and the west of Scotland are the most exposed to the maritime polar air mass which brings cool moist air; the east of Scotland and north-east England are more exposed to the continental polar air mass which brings cold dry air; the south and south-east of England are more exposed to the continental tropical air mass which brings warm dry air; Wales and the south-west of England are the most exposed to the maritime tropical air mass which brings warm moist air.