
Los Angeles has a Subtropical-Mediterranean climate (Köppen climate classification Csb on the coast, Csa inland), and receives just enough annual precipitation to avoid Köppen’s BSh (semi-arid climate) classification. Los Angeles enjoys plenty of sunshine throughout the year, with an average of only 35 days with measurable precipitation annually.
The average annual temperature in downtown is 66 °F (19 °C): 75 °F (24 °C) during the day and 57 °F (14 °C) at night. In the coldest month, January, the temperature typically ranges from 59 to 73 °F (15 to 23 °C) during the day and 45 to 55 °F (7 to 13 °C) at night. In the warmest month – August – the temperature typically ranges from 79 to 90 °F (26 to 32 °C) during the day and around 64 °F (18 °C) at night. Temperatures exceed 90 °F (32 °C) on a dozen or so days in the year, from one day a month in April, May, June, and November to three days a month in July, August, October, and to five days in September. Temperatures are subject to substantial daily swings; in inland areas, the difference between the average daily low and the average daily high is over 30 °F (17 °C). The average annual temperature of the sea is 63 °F (17 °C), from 58 °F (14 °C) in January to 68 °F (20 °C) in August. Sunshine hours are above 3,000 per year, from an average of 7 hours of sunshine/day in December to an average of 12 hours of sunshine/day in July.
The Los Angeles area is also subject to phenomena typical of a microclimate. As such, the temperatures can vary as much as 36 °F (20 °C) between inland areas and the coast. California also has a weather phenomenon called “June Gloom or May Grey”, which sometimes gives overcast or foggy skies in the morning at the coast, but usually gives sunny skies by noon, during late spring and early summer.
Downtown Los Angeles averages 15.14 inches (384.6 mm) of precipitation annually, which mainly occurs during the winter and spring (November through April) with generally moderate rain showers, but usually as heavy rainfall and thunderstorms during Winter storms. The coast gets slightly less rainfall, while the mountains get slightly more. However, the San Fernando Valley Region of Los Angeles can get between 16 and 20 inches of rain per year. Years of average rainfall are rare; the usual pattern is bimodal, with a short string of dry years (perhaps 7–8 inches/180–200 millimeters) followed by one or two wet years that make up the average. Snowfall is extremely rare in the city basin, but the mountains within city limits typically receive snowfall every winter. The greatest snowfall recorded in downtown Los Angeles was 2 inches (5 cm) in 1932. The highest recorded temperature in downtown Los Angeles is 113 °F (45 °C) on September 27, 2010, and the lowest recorded temperature is 24 °F (−4 °C) on December 22, 1944.