When is the first day of summer? It depends on whether you are referring to the astronomical or meteorological summer.
We often talk about it beginning to feel like summer when the days lengthen and warm, but what day does summer begin?
When we talk about the beginning of summer or any other season, we are usually talking about the day in our calendars that mark this date. This usually refers to the astronomical seasons which are a result of the Earth's axis and orbit around the sun. However, at the Met Office we often use a meteorological definition of the seasons.
The meteorological summer began on 01 June 2016 and ends on 31 August 2016.
The meteorological seasons consists of splitting the seasons into four periods made up of three months each. These seasons are split to coincide with our Gregorian calendar making it easier for meteorological observing and forecasting to compare seasonal and monthly statistics. By the meteorological calendar, spring starts on 1 March.
The seasons are defined as Spring (March, April, May), Summer (June, July, August), Autumn (September, October, November) and Winter (December, January, February).
This year the astronomical summer began on 20 June 2016 and ends on 22 September 2016.
The astronomical calendar determines the seasons due to the 23.5 degree tilt of the Earth's rotational axis in relation to its orbit around the sun. Both equinoxes and solstices are related to the Earth's orbit around the sun.
Earth's rotational axis and orbit around the sun determine the seasons (click to expand) Solstices and equinoxes are considered to be the astronomical transition points between the seasons and mark key stages in the astronomical cycle of the earth. In a year there are two equinoxes (spring and autumn) and two solstices (summer and winter). The dates of the equinoxes and solstices aren't fixed due to the Earth's elliptical orbit of the sun. The Earth's orbit around the sun means that in early January, the sun is closest (known as perihelion) and in early July it is most distant (aphelion).What is the weather usually like in summer?
The graphic below shows what the weather can be like during summertime showing the wettest, warmest, sunniest, driest and coldest summers on record.
Last updated: 22 June 2016