Chennai is located near the 13th north parallel and 80 degree longitude. The city stretches its 19 km length along the Coromandel coast and extends inland about 9 km at its widest. Its irregular shape covers about 172 sq km. It is a fairly low-lying strip of land, its highest point being only 60 m above sea level.

Chennai is trisected by two east-flowing rivers that traverse its width. The Cooum river almost divides the city into half and the Adyar river divides the southern half of the city into two. The historic buckingham canal runs nearly parallel to the coast almost through the entire length of the city.

The city has somewhat ungenerously described as having three seasons - hot, hotter and hottest. Indeed, except for four pleasant months, November to February, the weather is uniformly hot and humid.... May is the hottest season with the mercury sometimes touching 42 C and the mean temperature about 33 C. December and January are the coolest months with a mean temperature of 24 C. Howerver, the cool sea breeze (which sets in shortly after 3 PM daily) makes even the warmest of evenings bearable. But venturing out in between noon and 3 PM during April-August is best avoided.