Summer is the warmest of the four temperate seasons, between spring and autumn. At the summer solstice, the days are longest and the nights are shortest, with day-length decreasing as the season progresses after the solstice. The date of the beginning of summer varies according to climate, culture, and tradition, but when it is summer in the Northern Hemisphere it is winter in the Southern Hemisphere, and vice versa.
From an astronomical view, the equinoxes and solstices would be in the middle of the respective seasons, but a variable seasonal lag means that the meteorological start of the season, which is based on average temperature patterns, occurs several weeks later than the start of the astronomical season. According to meteorologists, summer extends for the whole months of June, July, and August in the northern hemisphere and the whole months of December, January, and February in the southern hemisphere. Under meteorological definitions, all seasons are arbitrarily set to start at the beginning of a calendar month and end at the end of a month. This meteorological definition of summer also aligns with the commonly viewed notion of summer as the season with the longest (and warmest) days of the year, in which daylight predominates. The meteorological reckoning of seasons is used in Austria, Denmark, and the former Soviet Union; it is also used by many in the United Kingdom, where summer is thought to extend from mid-May to mid-August. In Ireland, the summer months, according to the national meteorological service, Met Eireann, are June, July, and August. However, according to the Irish calendar, summer begins on May 1 and ends on August 1. School textbooks in Ireland follow the cultural norm of summer commencing on May 1 rather than the meteorological definition of June 1.
Days continue to lengthen from equinox to solstice, and summer days progressively shorten after the solstice, so meteorological summer encompasses the build-up to the longest day and a diminishing thereafter, with summer having many more hours of daylight than spring. Solstices and equinoxes are taken to mark the midpoints, not the beginnings, of the seasons. Midsummer takes place over the shortest night of the year, which is the summer solstice, or on a nearby date that varies with tradition.
The Western definition based on solstice to equinox is more frequently used where a temperature lag of up to half a season is common (usually June 20 or 21 in the Northern Hemisphere) to the autumn equinox. The summer season in the United States is commonly regarded as beginning on Memorial Day weekend (the last weekend in May) and ending on Labor Day weekend (the first weekend in September), more closely in line with the meteorological definition; the similar Canadian tradition starts summer on Victoria Day one week prior (although summer conditions vary widely across Canada’s expansive territory) and ends, as in the United States, on Labour Day.
According to Chinese astronomy, summer starts on or around May 5, with the solar term jieqi, also known as lixiai. i.e., “establishment of summer,” and it ends on or around August 6.
In southern and southeast Asia, where the monsoon occurs, summer is more generally defined as lasting from March to May/early June, the warmest time of the year, ending with the onset of the monsoon rains. Because the temperature lag is shorter in the oceanic temperate southern hemisphere, most countries in this region, especially Australia and New Zealand, use the meteorological definition of summer starting on December 1 and ending on the last day of February.
Summer is traditionally associated with hot, dry weather, but this does not occur in all regions. In areas of the tropics and subtropics, the wet season occurs during the summer. The wet season is the main period of vegetation growth within the savanna climate regime. Where the wet season is associated with a seasonal shift in the prevailing winds, it is known as a monsoon.
In the northern Atlantic Ocean, a distinct tropical cyclone season occurs from June 1 to November 30. The statistical peak of the Atlantic hurricane season is September 10. The Northeast Pacific Ocean has a broader period of activity but in a similar time frame to the Atlantic. The Northwest Pacific sees tropical cyclones year-round, with a minimum in February and March and a peak in early September. In the North Indian basin, storms are most common from April to December, with peaks in May and November. In the Southern Hemisphere, the tropical cyclone season runs from November 1 until the end of April, with peaks in mid-February to early March.
Thunderstorm season in the USA and Canada runs in the spring through summer. These storms can produce hail, strong winds and tornadoes, usually during the afternoon and evening.
Schools and universities typically have a summer break to take advantage of the warmer weather and longer days. In all countries, children are out of school during this time of year for summer break, although dates vary. In the United States, public schools usually end in early June, while colleges get out in early May. In India, school ends in April and resumes in early June. In England and Wales, school ends in mid-July and resumes again in early September; in Scotland, the summer holiday begins in late June and ends in mid-to-late August. In the Southern Hemisphere, school summer holiday dates include the major holidays of Christmas and New Year’s Day. School summer holidays in Australia and South Africa begin in mid-December and end in late January, with the dates varying between states.
A wide range of public holidays falls during summer.
- The feast of the Assumption of Mary on August 15 (or August 28 in the Orthodox Churches) in Austria, Belgium, Chile, Columbia, Croatia, Equator, France, German, Greece, Lebanon, Lithuania, Italy, Malta, Poland, Portugal, Romania, Slovenia, Spain and parts of Switzerland;
- Australia’s (Australia Day) national day on January 26th;
- Canada Day, Canada’s national day on July 1st;
- Bank Holidays in the United Kingdom and Ireland;
- The Day of Reconciliation in South Africa on December 16th;
- Olavsoka, national holiday in the Faroe Islands on July 29th;
- Independence Days – Afghanistan on August 19th, Argentina on July 9th, Algeria on July 5th, Bahamas on July 10th, Bahrain on August 15th, Belarus on July 3rd, Central African Republic on August 13th, Columbia on July 20th and August 7th, Djuouti on June 27th, Estonia on August 20th, Jamaica on August 6th, Kyrgyzstan on August 31. The Maldives on July 26th, Moldova on August 27th, Niger on August 3rd, Pakistan on August 14th, Philippines on June 12th, Slovakia on July 17th, Somalia on July 1st, Sweden on June 6th, Switzerland on August 1st, Tanzania on December 9th, Trinidad and Tobago on August 31st, Ukraine on August 24th, the United States on July 4th and Venezuela on July 5th.
People take advantage of the warmer temperatures by spending more time outdoors during the summer. Activities such as traveling to the beach and picnics occur during the summer months. Sports such as cricket, volleyball, skateboarding, baseball, softball, Canadian football, tennis, and water polo are played. Water sports also occur. These include water skiing, wakeboarding, swimming, surfing, and tubing. The modern Olympics have been held during the summer months every four years since 1896. The 2000 Summer Olympics in Sydney, however, were held during the Australian spring.
Summer is usually a low point in television viewing, and television schedules generally reflect this by not scheduling new episodes of their most popular shows between the end of May sweeps and the beginning of the television season in September, instead scheduling low-cost reality television shows and burning off commitments to already-canceled series. Conversely, the music and film industries generally experience higher returns during the summer than at other times of the year and market their summer hits accordingly. The summer season is also the most popular for animation movies to be released in movie theaters.
With most school-age children and college students (except those attending summer school) on summer vacation during the summer months, especially in the United States, travel and vacationing traditionally peaks during the summer, with the volume of travel in a typical summer weekend rivaled only by Thanksgiving. Teenagers and college students often take summer jobs in industries that cater to recreation.
