Climate

Sacramento has a Mediterranean climate (Köppen Csa), characterized by damp to wet, mild winters and hot, dry summers. The wet season is generally October through April, though there may be a day or two of light rainfall in June or September. The mean annual temperature is61.1 °F (16.2 °C), with monthly means ranging from 45.8 °F (7.7 °C) in December to 75.4 °F (24.1 °C) in July. Summer heat is often moderated by a sea breeze known as the "delta breeze" which comes through the Sacramento-San Joaquin River Delta from the San Francisco Bay.

Sacramento
Climate chart (explanation)
J F M A M J J A S O N D     3.7   54 39     3.5   61 42     2.8   66 44     1.2   72 47     0.7   80 51     0.2   87 56   0   92 59     0.1   92 58     0.3   88 56     0.9   78 51     2.1   64 43     3.3   54 39 Average max. and min. temperatures in °F Precipitation totals in inches
[show]Metric conversion

On average, 96 days in the year experience some degree of fog, which usually occurs in the morning (tule fog). The foggiest months are December and January. Tule fog can be extremely dense, lowering visibility to less than 100 feet (30 m) and making driving conditions extremely hazardous. Chilling tule fog events have been known to last for several consecutive days or weeks. During Tule fog events, temperatures do not exceed 50 degrees.

Snowfall is exceptionally rare in Sacramento, which is only 25 feet (7.6 m) above sea level; at least once a year during the winter months, snow flakes are reported but rarely become heavy or stick to the ground. The all-time record snowfall was 3.5 inches (9 cm), which occurred on January 4, 1888. Dustings occur every 5–10 years, with up to an inch accumulation in outlying areas. During especially cold winter and spring storms, intense showers do occasionally produce a significant amount of hail, which can create hazardous driving conditions. Significant snow accumulations occur each year in the foothills located 40 miles (64 km) east of the city. Sacramento had a brief snowfall on January 28, 2002. Snow accumulation happened on December 7, 2009. Click here to see a video of rare snowfall in Sacramento.

On average, there are 74 days where the high exceeds 90 °F (32 °C), and 15 days where the high exceeds 100 °F (38 °C); On the other extreme, freezing nights occur 16 nights per year.^[17] At Sacramento Executive Airport, extremes have ranged from 18 °F (−8 °C) on December 22, 1990 to 115 °F (46 °C) on June 15, 1961.^[17]

The average annual precipitation is 17.93 inches (455 mm).^[18] On average, precipitation falls on 62 days each year in Sacramento, and nearly all of this falls during the winter months. Average January rainfall is 3.84 inches (98 mm),^[19] and measurable precipitation is rare during the summer months. In February 1992, Sacramento had 16 consecutive days of rain, resulting in an accumulation of 6.41 inches (163 mm) for the period (163 mm). A record 7.24 inches (184 mm) of rain fell on April 20, 1880. On rare occasions, monsoonal moisture surges from the Desert Southwest can bring upper-level moisture to the Sacramento region, leading to increased summer cloudiness, humidity, and even light showers and thunderstorms. Monsoon clouds do occur, usually during late July through early September. Sacramento is the second most flood susceptible city in the United States after New Orleans.^[20]

Sacramento has been noted as being the sunniest location on the planet for four months each year, from June through September. It also holds the distinction as the sunniest month of any location in the world; July in Sacramento averages 14 hours and 12 minutes of sunshine per day, amounting to approximately 98% of possible sunshine.[1]