Climate of Minneapolis, Minnesota

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The Climate of Minneapolis, in the U.S. state of Minnesota, is typical of cities located in the Midwestern United States. However, due to the city's northerly location, it generally runs on the cold side. Winters are particularly punishing with bitter cold arctic air masses pushing their way south from Canada. Of all the major metropolitan areas in the U.S., the Minneapolis-St.Paul metropolitan area has the coldest annual mean temperature of only 7.48 °C (45.46 °F). There are four distinct seasons, with characteristic large changes in temperatures over a short period of time. Winters are bitterly cold and dry, and summers are warm, sometimes hot, and frequently humid. The city experiences a full range of precipitation and related weather events, including snow, sleet, ice, rain, thunderstorms, and fog.

1 Temperatures
2 Precipitation
3 General climatology
4 Notes and references

[edit] Temperatures

Temperatures in Minneapolis vary greatly throughout the year, and often in shorter periods as well. For example, in the month of March, 1948, the temperatures ranged from -27 °F (-34 °C) to 70 °F (21 °C). The warmest month of the year is July, when the high temperature averages 83 °F (29 °C), and overnight low temperatures average 63 °F (17 °C). In January, the coldest month, high temperatures average 22°F (-5°C), and overnight low temperatures average 4 °F (-15 °C). The highest temperature ever recorded in Minneapolis was 108 °F (42 °C) on July 14, 1936. The coldest temperature on record is -41 °F (-41 °C) on January 21, 1888.

Monthly average temperatures
Month	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
High (°F)	22	29	41	57	70	79	83	80	71	58	40	26
°C	-5	-2	5	14	21	26	29	27	22	15	5	-3
Low (°F)	4	12	23	36	48	58	63	61	51	39	25	11
°C	-15	-11	-5	2	9	15	17	16	10	4	-4	-12

Record temperatures by month
Month	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Record High (°F)	59	64	83	95	106	104	108	103	104	90	77	63
(°C)	15	18	29	35	41	40	42	39	40	32	25	17
Record Low (°F)	-41	-33	-32	2	18	34	43	39	26	10	-25	-39
(°C)	-41	-36	-35	-17	-9	1	6	4	-3	-12	-32	-39

[edit] Precipitation

The type and amount of precipitation which occurs throughout the year in Minneapolis is very variable, as with many Midwestern cities. There can be floods as well as long dry spells. In the winter months, which in the northern Midwest comprise the period November through March, snow predominates. In the warm summer months from May to September, rain, usually in the form of thunderstorms, is the norm. Months which fall between these two periods can often see a mix of precipitations, with rain, snow, and occasionally ice all falling in relatively short periods. In an average year in Minneapolis, precipitation of all forms totals 29.41 inches (747 mm), with an average annual snowfall of 45.8 inches (1163 mm). On average, the wettest month is June, when 4.34 inches (110 mm) of precipitation falls, mostly due to summer thunderstorms. The driest month is February, when only 0.79 inches (20 mm) falls.

The wettest year in the history of Minneapolis was 1911 when 40.15 inches (1020 mm) of precipitation fell. In a strange twist, the driest year on record in the city was 1910, when only 11.54 inches (293.1 mm) of precipitation was measured. The snowiest winter on record was that of 1983-84, when 98.4 inches (250 cm) of snow fell, the least snowy winter was that of 1930-31, when only 14.2 inches (36 cm) of snow fell.

Average Precipitation by month
Month	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Total
Precipitation (inches)	1.04	0.79	1.86	2.31	3.24	4.34	4.04	4.05	2.69	2.11	1.94	1.00	29.41
Millimeters	26.4	20.1	47.2	58.7	82.3	110.2	102.6	102.9	68.3	53.6	49.3	25.4	747.0

Average Snowfall by month
Month	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Total
Snowfall (inches)	9.8	8.4	10.7	2.8	0.1	--	--	--	--	0.5	7.9	9.3	49.5
Centimeters	24.9	21.3	27.2	7.1	0.25	--	--	--	--	1.3	20.0	23.6	125.7

[edit] General climatology

Minneapolis, due to its location in the Midwestern United States, experiences a continental climate characterized by wide variations in temperature and precipitation between the seasons. Also, the prevailing weather patterns during each season tend to differ just as greatly as the temperatures in a particular given month. Each season has distincitive upper air patterns which bring different weather conditions. However, another feature of a continental climate is that weather patterns can be unpredictable. For example, an Alberta clipper, a low-pressure system originating in the province of Alberta in Canada, would be a common occurrence in winter in Minneapolis, but with the general unpredictability of weather in a continental climate, such a storm system could occur in spring, or in late autumn. Hot weather, though usually confined to June, July, and August, can someimtes begin as early as April or May, and could spill over into September.

As with many other Midwestern cities, winter in Minneapolis is characterized by cold, usually below freezing, temperatures and snowfall. High-pressure systems which descend from the Canadian plains bring light winds, clear skies, and bitterly cold weather. Alberta clippers alternate with these high-pressure systems, bringing slightly warmer temperatures and fairly regular snowfall. Larger storm systems, often Panhandle Hooks or other storms originating from the Pacific Ocean, can bring large amounts of snow and even blizzard conditions. A vigorous jet stream brings high and low-pressure systems through in quick succession, which can cause large temperature variations over a short period of time.

In spring, much of the Midwest starts to experience severe thuderstorms as storm systems move off of the Pacific Ocean and combine with humid and increasingly warmer air from the Gulf of Mexico. In April Minneapolis generally finds itself on the northern (cooler) side of strong storm systems, leading to daytime temperatures in the 40s and 50s with light rain over large areas being common. However as April moves on into May and June and the northern hemisphere's air contines to warm, the tracks of these storm systems gradually shifts northward, putting Minneapolis in a greater risk for thunderstorms. Some of these storms produce large hail and even tornadoes. The peak tornado month in Minneapolis is June, when the jet stream is still vigorous enough to bring strong storm systems into the area. These vigorous storms can produce tornado outbreaks and long-lived destructive thunderstorms known as derechos. High-pressure systems become less potent and become less associated with colder air, leading to a rapid seasonal warmup. Still, cold spells and even snowstorms well into late April and early May are not unheard of.

In summer, hot and humid temperatures predominate. A main feature of summer weather in the Minneapolis area and the Midwestern United States as a whole is the weakening of the jet stream, leading to slower movement of air masses, and a general increase in the stability of temperatures. Even though storm systems are much weaker in the summer, Minneapolis is located far enough north where cooler, drier shots of Canadian air frequently move in behind cold fronts. The cooler air typically does not stick around very long though and is quickly replaced by the warmer and more humid Gulf air. The drier air moving into hot and humid air keep the threat of thunderstorms and tornadoes around in Minneapolis through July and August. ^[1].

Autumn weather in the Minneapolis area is largely the reverse of spring weather. The jet stream, which tends to weaken in summer, begins to restrengthen, leading to a quicker changing of weather patterns and an increased variability of temperatures. Storms systems associated with the Pacific Ocean again become more common, with each successive storm system bringing colder temperatures until the rain begins to change over to snow, generally in October.