10 facts about summer

1. Dog days of summer

The phrase 'dogs days of summer' used to refer to sweltering summer days has more to do with the stars than dogs.

The Roman's 'dies caniculares' began towards the end of July when the star Sirius (known as the Dog Star) began to rise in the sky just before the Sun.

The star was so bright that the Romans believed it gave extra heat to the sun and was responsible for hot days in summer.

2. It's the most thundery time of the year

More thunderstorms occur during the summer than at any other time of the year.

The warmth of summer often provides the perfect conditions of rising air and moisture required for the creation of thunderstorms.

In the UK, they are most likely to occur in the East Midlands and the southeast.

3. Crickets get chirpy

Next time you hear the sound of crickets chirping on a balmy summer evening, why not try this simple trick to find out the temperature.

The frequency of a cricket's chirps is consistent with air temperature, so you simply need to count how many chirps there are over 25 seconds then divide by 3 and add 4 to tell you the temperature in Celsius.

4. Snow in June

On 2 June 1975, snow showers forced the abandonment of several cricket matches across the country.

The coldest temperature ever recorded in summer in the UK is -5.6 °C recorded on 9 June 1955 in Dalwhinnie, and again on 1 and 3 June 1962 in Santon Downham in Norfolk.

5. Height of summer

Did you know that on a hot day in Paris, the Eiffel Tower grows taller?

The tower is constructed from iron and when this is warmed it expands, causing the structure to grow by up to 17 cm.

6. Midnight match

Every year on the summer solstice, a unique baseball game is played at the Growden Memorial Park known as the Midnight Sun Game.

Taking place in Fairbanks, Alaska, the Sun is out for almost 24 hours on the solstice and so the game begins at 10:30 pm and ends around 1:30 am without any artificial lighting.

The tradition originated in 1906 and has been played every year since 1960 by the Alaska Goldpanners.

7. First day of summer

This year the astronomical summer began on 21 June. The astronomical calendar determines the seasons due to the 23.5 degrees of tilt of the Earth's axis, in its orbit around the Sun.

The meteorological summer begins on 1 June. The meteorological seasons are split into three months each. They coincide with our Gregorian calendar, making it easier for observing and forecasting to compare seasonal and monthly statistics.

8. Manhattenhenge

Twice a year around 28 May and 12 July, New York is home to a fascinating sunset phenomenon.

Owing to the city's design on a grid rotated 29 degrees clockwise from true east-west, twice a year the Sun sets directly at the end of the many of New York's major streets. This creates a spectacular sunset to see the Sun slightly above the horizon and nestled between the rows of buildings.

Similarly, Milton Keynes' central road is designed so that when the Sun rises on the solstice, it shines straight down Midsummer Boulevard and reflects in the glass of the train station.

9. Top temperatures

The warmest ever summer in the UK was in 2018 when daytime temperatures averaged 15.76°C, narrowingly exceeding the previous record of 15.75°C in 2006.

The hottest daily temperature ever recorded in the UK was on 19 July 2022 when Coningsby, Lincolnshire, recorded a sweltering 40.3°C.

10. The longest day of the year is in summer

The summer solstice marks the point when the Sun reaches its highest point in the sky. This is the longest day of the year and after this point, the days slowly begin to get shorter until the winter solstice which occurs around 21 December.

At the same time as the Northern Hemisphere experiences the summer solstice, the Southern Hemisphere has a winter solstice marking the shortest day of the year.