Western European Summer Time
Western European Summer Time is a summer daylight saving time scheme, 1 hour ahead of Greenwich Mean Time and Coordinated Universal Time. It is used in:
- the Canary Islands
- Portugal
- the Faroe Islands
- United Kingdom, which uses British Summer Time
- Ireland, which uses Irish Standard Time . Also sometimes erroneously referred to as "Irish Summer Time".
The start and end dates of the scheme are asymmetrical in terms of daylight hours: the vernal time of year with a similar amount of daylight to late October is mid-February, well before the start of summer time. The asymmetry reflects temperature more than the length of daylight.
Ireland observes Irish Standard Time during the summer months and changes to UTC+00:00 in winter. As Ireland's winter time period begins on the last Sunday in October and finishes on the last Sunday in March, the result is the same as if it observed summer time.
Usage
The following countries and territories use UTC+01:00 during the summer, between 1:00 UTC on the last Sunday of March and 1:00 UTC on the last Sunday of October.- Canary Islands, regularly since 1980
- Faroe Islands, regularly since 1981
- Ireland
- * 1916–1939 summers IST
- * 1940–1946 all year IST
- * 1947–1968 summers IST
- * 1968–1971 all year IST
- * 1972– summers IST
- Portugal
- * Continental Portugal
- ** 1916–1921 summers WEST
- ** 1924 summer WEST
- ** 1926–1929 summers WEST
- ** 1931–1932 summers WEST
- ** 1934–1941 summers WEST
- ** 1942–1945 summers WEST
- ** 1946–1966 summers WEST
- ** 1966–1976 all year WEST/CET
- ** 1977–1992 summers WEST
- ** 1992–1996 winters WEST/CET
- ** 1996– summers WEST
- * Madeira, regularly since 1982
- The United Kingdom
- * 1916–1939 summers BST
- * 1940–1945 all year BST
- * 1946 summer BST
- * 1947 summer BST
- * 1948–1968 summers BST
- * 1968–1971 all year BST
- * 1972– summers BST