The lowest temperature recorded recorded in the State was at Boca, 5,532 feet in Nevada County, when a reading of minus -45° F. was observed on January 20, 1937.  Here at Boca where sub-freezing temperatures have been recorded in every month of the year, the long-term average minimum for January is only 8° F.  Greenland Ranch, on the other hand, at an elevation of 168 feet below sea level, has reported a maximum temperature of 134° F.  This is the highest temperature observed anywhere in the United States, and occurred on July 10, 1913.  This is an area where temperatures are persistently high throughout the summer though they are comfortably cool in winter.  In the summer of 1917 there were 43 consecutive days with maximum readings of 120° F. or higher at Greenland Ranch.

GROWING SEASON – The average length of the growing season, as limited by occurrences of 32° F. temperatures, ranges from 365 days on the south coast to less than 50 days at high elevations of the Sierra Nevada.  Most coastal valleys and the Central Valley have a freeze-free season of 225 to 300 days.  The agricultural area within the southeastern desert basin reports a growing season ranging from 225 to 325 days long, but the season is limited to 100 to 125 days in the northeastern interior.

WINDS – California lies within the zone of prevailing westerlies and on the east side of the semi-permanent high pressure area of the northeast Pacific Ocean.  The basic flow in the free air above the State, therefore, is from the west or northwest during most of the year.  The several mountain chains within the State, however, are responsible for deflecting these winds and, except for the immediate coast, wind direction is likely to be more a product of local terrain than it is of prevailing circulation.