Climate of Milwaukee, Wisconsin

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The Climate of Milwaukee, Wisconsin is a prime example of a continental climate, with wide variations in temperature and precipitation in short periods of time as well as four distinct seasons. The city's climate is also strongly influenced by nearby Lake Michigan, which creates almost two entirely different climates within the Milwaukee area. The Urban heat island effect also plays a large role in the city's climate, insulating it from winter cold (at least compared to rural areas in Wisconsin), but exacerbating summer heat. The Milwaukee-Racine-Waukesha Metropolitan Area is the second coldest in the entire country with a mean annual temperature of 9.04 C (48.27 F) (coldest being the Minneapolis-St.Paul Metropolitan Area in the neighboring state of Minnesota).

Environmental organization SustainLane ranked Milwaukee along with Mesa, Arizona the least likely to suffer natural disasters, in a study of fifty US cities measuring the risk of a natural disaster striking the city. The study used the possibilities of "hurricanes, major flooding, "catastrophic hail, tornado super-outbreaks, and earthquakes" as criteria. ^[1]

[edit] Temperatures

Due to the city's location in the Midwestern United States, Milwaukee experiences a continental climate with wide variations in temperatures over short periods, especially in spring and autumn. The warmest month of the year is July, when the average high temperature is 81 °F (28 °C), and the overnight low is 63 °F (17 °C). The coldest month of the year is January, when the average high. temperature is only 28 °F (-2 °C). Low temperatures in January average 13 °F (-11 °C).

Monthly average temperatures in Milwaukee, Wisconsin
Month	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
High (°F)	28	33	43	54	66	76	81	79	72	60	46	33
°C	-2	1	6	12	19	25	28	26	22	15	8	1
Low (°F)	13	18	27	36	46	56	63	62	54	43	31	19
°C	-11	-8	-3	2	8	13	17	16	12	6	-1	-7

The highest temperature ever recorded in Milwaukee is 105 °F (41 °C) on July 17, 1995. The coldest temperature ever officially recorded at Milwaukee is -26 °F (-32 °C), on both January 17, 1982 and February 4, 1996. The former occasion is referred to as "Cold Sunday," due to the extreme cold felt in many locations in the United States on that day. Locations in suburbs just north of the city recorded temperatures as low as -40 °F (-40 °C).

Record High and Low Temperatures by month at Milwaukee, Wisconsin
Month	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Record High (°F)	62	68	82	91	94	101	105	103	98	89	77	68
°C	17	20	28	32	34	38	41	39	37	31	25	20
Record Low (°F)	-26	-26	-10	12	21	33	40	36	28	18	-5	-20
°C	-32	-32	-23	-11	-6	1	4	2	-2	-8	-20	-29

[edit] Precipitation

Milwaukee's climate allows for a wide variation in both type and amount of precipitation throughout the year. Rain can fall all year round, but is rare winter months such as December, January, and February. It only occurs in these months when combined with unseasonably warm weather, as the high temperatures in these months are frequently below the freezing point of water. Snow falls in and around Milwaukee regularly from late November until early March. However, snow can fall as early as late September, or as late as the end of May. During the transition into and out of winter, various mixed forms of precipitation can occur, such as sleet, ice, and freezing rain. Ice storms, while rare, are not impossible. These types of precipitation tend to occur mainly in November and March, due to these months serving as transitions between winter and more mild seasons.

An average year in Milwaukee sees 34.81 inches (884.2 mm) of precipitation, with a yearly average snowfall of 47.0 inches (1.19 m). The city receives more snowfall than cities even slightly inland, due to lake effect snow produced by Lake Michigan. Because Milwaukee lies on the western shore of Lake Michigan, east winds, which are relatively uncommon in the Midwest, favor heavier snowfall on the Milwaukee side of the lake. Milwaukee receives far less snow than cities on the eastern shore of the lake, such as Grand Rapids, Michigan, which receive extra snowfall when more common west winds blow. However, just like every other aspect of Milwaukee's weather, the amount of snowfall in any given winter season is highly variable; the month of December, 2000 saw 49.5 inches (1.26 m) of snow, more than the annual average. However, almost no snow fell in the remaining months of the 2000-2001 snow season, January recorded just under 2.0 inches (51 mm).

The wettest month of the year is August, when 4.03 inches (102 mm) of precipitation falls, mainly as rainfall due to thunderstorms. Long-duration rain events are uncommon in the summer months, usually occurring only in April or October. Thunderstorms are the main precipitation events from May until September, and Milwaukee experiences an extended tornado season which lasts from late March until early June. The driest month is February, when only 1.65 inches (41.9 mm) of precipitation falls, almost entirely as light, low moisture content snow resulting from the cold, dry air masses which dominate.