Between 30 and 42S winds become increasingly more westerly and with it more frequent more intense precipitin is found with increasing latitude. During winter the south Pacific anticyclone is in its southernmost position and migrates northwards during the winter allowingcold front to reach the coast of Chile bringing rainfall. The Bio-Bio river (37S) marks the southern border of the pure winter rainfall season. South of this river summer rains start to be more important, so that in
the southern central part summer rains contribute to about 20% to the total annual rainfall. The temperature decreases with latitude and altitude and the annual range increases especially in the central valley away from the coast.

PRECIPITATION	TEMPERATURE

WET-DAY FREQUENCY Number of days/mo with Precipitation	GROUND-FROST FREQUENCY Number of days/mo with Min. Temp. < 0 deg. C

Southern Central Chile

Has the same precipitation regime as the central part of Chile, but with increasing latitude rainfall amount increase and temperature decreases. In hand with these gradual changes, days of wet days increase and days per month with temperature below freezing point.
 
 

PRECIPITATION	TEMPERATURE

WET-DAY FREQUENCY Number of days/mo with Precipitation	GROUND-FROST FREQUENCY Number of days/mo with Min. Temp. < 0 deg. C