We think of the equinoxes as always occurring on March 21 and September 21, but this can vary a day or two either way depending on the cycle of leap years.
This year, in 2010, the northern hemisphere end of summer occurs on September 23, 2010. at 03:09 Greenwich Mean Time. If you live in North America, summer ends for you late in the evening of September 22, depending on your time zone.
The U.S. Naval Observatory lists the dates and times for the solstices and equinoxes on their "Earth's Seasons" web page at the link below.
September 21
September 21
A Summer Night ended on 1962-09-21.
9-21-12
12:00 A.M. on December 21, 2012. This is the summer equinox... Also known as "Doomsday" to some...
Summer ends on March 21 everywhere in the Southern Hemisphere, where you can find Antarctica.
In all northern hemisphere time zones that are ahead of UTC, including British Summer Time, spring of 2012 ends (and summer begins) on June 21. In all northern hemisphere time zones equal to or behind UTC it happens on June 20. In southern hemisphere time zones that are at least 13 hours ahead of UTC, including New Zealand Daylight Saving Time, spring of 2012 ends (and summer begins) on December 22. Throughout the rest of the southern hemisphere it happens on December 21.
June 21 6:08am
the summer solstice begins on June 21 for 2010.
In 1929, British Summer Time began on 21 April and ended on 6 October.
It starts at 17:16 UTC on June 21.
The Long Hot Summer - 1965 A Time to Die 1-21 was released on: USA: 16 February 1966