<Tr> <Td_colspan="14"> Source: NOAA (relative humidity and sun 1961--1990), </Td> </Tr> <P> Winter temperatures are not as extreme as might be expected, given the elevation 4,300 feet (1,310 m) and latitude (40 ° 45'N) of the city . The Rocky Mountains to the east and northeast of the state block most cold waves from polar highs positioned in the Great Plains from reaching the city . The frigidly cold air that does affect the city must come directly from the north or north - northwest from western Canada through fewer and lower intervening mountains . Temperatures seldom fall below 0 ° F (− 17.8 ° C); Salt Lake City has experienced sub-zero temperatures during only 4 storm cycles in the last 10 years . However, the average sub-zero days in a year is 2.3. (1) Salt Lake City averages 26 days with high temperatures at or below freezing. (2) In winter, warm air from the Desert Southwest is usually only drawn up to the city in advance of a cold front arriving from the northwest . </P> <P> January is the coldest month with an average temperature of 29.2 ° F (− 1.6 ° C). Salt Lake City's record low maximum temperature is 2 ° F (− 16.7 ° C), set on December 22, 1990, during an extended period of frigid Arctic air, and its overall record low temperature is − 30 ° F (− 34.4 ° C), set on February 9, 1933 during a historic cold air surge from the north . During spring, temperatures warm steadily and rapidly . Wintry weather is usually last experienced by early - to - mid April . Summery weather first arrives in early to mid May; the earliest 90 ° F (32.2 ° C) temperature on record was on May 2 . Major cold fronts typically stop arriving in late May or early June . </P> <P> Summer temperatures are hot, although are moderated somewhat by the cool breezes from the Great Salt Lake and by the city's elevation . The lack of cold fronts in summer allows the temperatures to become consistently hot due to powerful, long - lasting high pressure . Occasional thunderstorms give almost the only relief in temperatures . In an average year, 5 days hotter than 100 ° F (37.8 ° C), 23 days greater than 95 ° F (35.0 ° C), and 56 days greater than 90 ° F (32.2 ° C) can be expected . (3). However, such days also have very low humidity . The low humidity and the altitude create ideal conditions for radiational cooling, and hence, large swings in temperature . Summer nights are rather cool; the record low even in July is 40 ° F (4.4 ° C). July is the warmest month, with an average temperature of 77.0 ° F (25.0 ° C). Salt Lake City's record high minimum temperature is 81 ° F (27.2 ° C), set on July 18, 2016, (4) and its record high temperature is 107 ° F (42 ° C), first set on July 26, 1960 and again on July 13, 2002 (although the temperature in 2002 was slightly higher). The last summer - like weather is typically experienced in mid-September; the latest 90 ° F (32 ° C) temperature was recorded on September 30 . Temperatures cool down rapidly in fall . The first major cold fronts typically arrive anytime from mid-September to early October . The first winter - like weather is usually experienced in early - to - mid November . </P>

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