Tamil Nadu has a tropical climate with little difference in
temperature in summer and winter. April and May are the
hottest months with the mercury often soaring above the 40ºC
mark. Coastal regions get uncomfortably warm and humid during
these months but the nights are usually cool, thanks to the
sea breeze that sets in during the afternoon. Summer
temperatures are quite equable in the foothills of the Ghats.
Hill stations are pleasant and the maximum temperature rarely
rises above the mid twenties. A mild winter falls between
November and February when the climate is pleasantly cool.
Minimum temperatures in the plains rarely dip below 20º C,
while in the hills the mercury may drop to 5º C or below. The
north-east monsoon brings rain in spurts between October and
December. The average annual rainfall, ranges between 25 and
75 inches (635 and 1,905 mm) a year. Highest precipitation
occurs in the Nilgiris and other hill areas with the least in
the Ramanathapuram and Tirunelveli districts.
