Climate of Salt Lake City
The climate of Salt Lake City, Utah features cold and snowy winters, hot and dry summers, and modest to light seasonal rainfall.
The city has four distinct seasons: a cold, snowy winter; a hot, dry summer; and two relatively wet transition periods.
The Pacific Ocean is the primary influence on the weather, contributing storms from about October to May, with spring being the wettest season.
Snow falls frequently during the winter, contributed largely by the lake-effect from the Great Salt Lake.
The Rocky Mountains to the east and north usually block powerful polar highs from affecting the state during the winter.
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.
[2] In winter, warm air from the surrounding Desert Southwest is usually only drawn up to the city in advance of a cold front arriving from the northwest.
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.
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 .
The low humidity and the altitude create ideal conditions for radiational cooling, and hence, large swings in temperature.
The summer monsoon rising from Mexico and Arizona passes through the region beginning in mid-July and continuing into September, bringing intense but short-lived thunderstorm activity.
Many of these thunderstorms consist of dry lightning, which occurs when humidity is too low to support rainfall and the rain evaporates before reaching the ground.
The record precipitation for a single month occurred in September 1982, with 7.04 inches (179 mm), largely due to the remnants of Hurricane Olivia.
The four major ski resorts located in canyons surrounding the city regularly average more than 500" of snow per year.
\ The phenomena El Niño and La Niña also affect precipitation along the Great Basin, bringing occasional cycles of drought and flooding.
Triggered by a powerful El Niño, an exceptionally large snowpack caused flooding and massive damage.
A 2010 study indicates that this record event occurred during an overlapping period of three prominent climate cycles that are unique in the region.
Humidity is only high enough and temperatures cold enough for fog to occur during mid-winter, although haze and smog can be found year-round.
Consequently, inversions are rare in spring and fall, when the weather takes on a more progressive pattern, with frequent fronts moving through.
[8] Such recurring and persistent patterns of inversions follow a unique timescale of about 30 days,[9] providing a means for long-range weather prediction.
Accompanied by subsequent snowstorms and a very cold January and February, snow from this storm remained on the ground for the remainder of the winter.
Near record-setting snowpack in the mountains during the 2004 to 2005 season, as well as heavy spring rains, ended the drought nearly statewide.
In late January, heavy rains overflowed the Santa Clara River in Washington County in the southwest corner of the state, destroying several homes in Ivins, Santa Clara, and Saint George, and essentially cutting off the small town of Gunlock.
Heavy spring rains in late April caused widespread but minor flooding in northern Utah.
