Climate of Miami

South Florida has a tropical climate, according to the Köppen climate classification, with a hot and wet season in summer, and a warm, dry season in winter.

The climate of Miami is classified as having a tropical monsoon climate with hot and humid summers; short, warm winters; and a marked drier season in the winter. Its sea-level elevation, coastal location, position just above the Tropic of Cancer, and proximity to the Gulf Stream shape its climate.

With January averaging 69.2 °F (20.7 °C), winter features warm temperatures; cool air usually settles after the passage of a cold front, which produces much of the little amount of rainfall. Lows sometimes fall to or below 50 °F (10 °C), with an average 3 such occurrences annually,[1] but rarely 40 °F (4 °C); from 1981 to 2010, temperatures reached that level in only eight calendar years.[2] Highs generally reach 70 °F (21 °C) or higher, and fail to do so on only an average of 12 days annually.

The wet season usually begins during the month of May and continues through mid-October. During this period, temperatures are in the mid 80s to low 90s (29–35 °C), accompanied by high humidity, though the heat is often relieved by afternoon thunderstorms or a sea breeze that develops off the Atlantic Ocean, which then allow lower temperatures, but conditions still remain very muggy. Much of the year's 61.9 inches (1,570 mm) of rainfall occurs during this period. Extreme temperatures range from 27 F[3] on February 3, 1917,[4] to 100 °F on July 21, 1942, (−2.8 to 38 °C), the only triple-digit (°F) reading on record;[5] the more recent freezing temperature seen at Miami International Airport was on December 25, 1989.[6] The highest daily minimum temperature is 84 °F (29 °C) on August 4, 1993 and September 7, 1897 (although the corresponding record for Miami Beach is 90 °F or 32 °C on July 17, 2001), and conversely, the lowest daily maximum temperature is 45 °F (7 °C) on February 19, 1900.

While Miami has never officially recorded any accumulating snowfall since records have been kept, there were non-accumulating snow flurries in some parts of the city on January 19, 1977 during the cold wave of January 1977.[7][8][9] Weather conditions for the area around Miami were recorded sporadically from 1839 until 1900, with many years-long gaps. A cooperative temperature and rainfall recording site was established in December 1900 in what is now Downtown Miami. An official Weather Bureau Office opened in Miami in June 1911.[10] A record setting 12-day cold snap in January 2010 was the coldest period since at least the 1940s.[11]

Miami receives abundant rainfall, one of the highest among major cities in the United States. Most of this rainfall occurs from mid-May through early October. Miami has an average annual rainfall of 61.9 inches (1,570 mm), whereas nearby Fort Lauderdale and Miami Beach receive 66.5 inches (1,690 mm) and 51.7 inches (1,310 mm), respectively, which demonstrates the high local variability in rainfall rates.[6]

Miami reports more thunderstorms than most US cities, with about eighty days per year having thunder reported. These storms are often strong, with frequent lightning and very heavy rain. Occasionally, they can be severe with damaging straight line winds and large hail. Tornadoes and waterspouts sometimes occur, although violent tornadoes of the type seen in other parts of the United States are rare in Florida.

During El Niño events, Miami becomes cooler than normal during the dry season with above average precipitation. During La Niña, Miami becomes warmer and drier than normal.

While the climate for much Florida is humid subtropical, South Florida qualifies as one of several tropical classifications (Köppen Aw, As, Am, or Af). Southeastern Florida falls into USDA zone 10b to 11b for plant hardiness,[12] where annual extreme low temperatures range from 30 to 40 °F (−1 to 4 °C), versus zone 9 in Central Florida, and zone 8 in northern Florida.[13] With global warming, the urban heat island effect, as well as Biscayne Bay as a buffer, the waterside downtown area and the barrier islands including Miami Beach made it into hardiness zone 11a by 2012.[14] Miami Beach has virtually no freezing weather in its history and few instances of sub-40 °F (4 °C) weather.[15][1]

Miami
Climate chart (explanation)
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F
M
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M
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1.6
 
 
76
60
 
 
2.3
 
 
78
62
 
 
3
 
 
80
65
 
 
3.1
 
 
83
68
 
 
5.3
 
 
87
73
 
 
9.7
 
 
90
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6.5
 
 
91
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8.9
 
 
91
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9.9
 
 
89
77
 
 
6.3
 
 
86
74
 
 
3.3
 
 
82
68
 
 
2
 
 
78
63
Average max. and min. temperatures in °F
Precipitation totals in inches
Source: NOAA/NWS
Metric conversion
J
F
M
A
M
J
J
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O
N
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41
 
 
25
16
 
 
57
 
 
26
17
 
 
76
 
 
27
18
 
 
80
 
 
28
20
 
 
136
 
 
31
23
 
 
246
 
 
32
24
 
 
165
 
 
33
25
 
 
226
 
 
33
25
 
 
250
 
 
32
25
 
 
161
 
 
30
23
 
 
83
 
 
28
20
 
 
52
 
 
26
17
Average max. and min. temperatures in °C
Precipitation totals in mm
  1. ^ a b "Station Name: FL MIAMI INTL AP". NOAA. Retrieved 2014-01-18.
  2. ^ "Fort Lauderdale-Hollywood International Airport Equals All Time High Temperature Record June 22; Daily Records Fall at Miami and West Palm Beach" (PDF). National Oceanic and Atmospheric Administration. Retrieved June 9, 2011.
  3. ^ "Almanac for Miami, FL". Miami Herald Weather. Retrieved January 6, 2017.
  4. ^ David Fairchild (October 1, 1918). "Cold Resistance of a Hybrid Anona" (PDF). USDA National Plant Germplasm System. Archived from the original (PDF) on February 25, 2016. Retrieved December 29, 2015.
  5. ^ "Highest and Lowest Temperature of Record". National Weather Service.
  6. ^ a b Cite error: The named reference NOAA was invoked but never defined (see the help page).
  7. ^ "Maine shivers at -29: Snow falls in Florida". Associated Press. The Baltimore Sun. January 20, 1977. p. A1. "Temperatures dipped into the 30s in southern Florida, with snow flurries reported even in Miami Beach."
  8. ^ Lardner Jr., George; Meyers, Robert. "Miami Is Hit by First Recorded Snow: State of Emergency Is Eyed for Virginia Thousands Idled as Cold Closes Factories, Businesses". The Washington Post. January 20, 1977. p. A1. The meandering jet stream in the upper atmosphere sent flurries of genuine snow onto Miami's palm trees. ... It was the farthest south that snow has been reported in the United States since the record books were started in the 19th century. ... The snow flurries in Miami will be only an asterisk in the record books since they didn't fall on any of the National Weather Service's recording stations in the area, but they were genuine."
  9. ^ Khiss, Peter. "New York High is 26 as the South Shivers: Florida Snow Causes Emergency Gas Shortage Widespread". The New York Times. January 20, 1977. p. 1. "Florida officially recorded snow for the first time yesterday in Palm Beach County, 65 miles north of Miami, and even that city had flurries, although not at the official stations at its airport or nearby Coral Gables."
  10. ^ "History of National Weather Service Forecast Office-Miami, Florida". National Oceanic and Atmospheric Administration. Retrieved 2007-08-19.
  11. ^ "Summary of Historic Cold Episode of January 2010 Coldest 12-day Period Since At Least 1940" (PDF). NOAA. January 14, 2015. Retrieved December 21, 2015.
  12. ^ "USDA Plant Hardiness Zone Map" (PDF). NOAA. Retrieved December 21, 2015.
  13. ^ Kridler, Chris (5 March 2011). "Freeze-frazzled Brevard County gardeners seek hardier plants". Florida Today. Melbourne, Florida. pp. 1D. Retrieved December 22, 2015.
  14. ^ "About - Maps & Gardening". United States Department of Agriculture (USDA). Retrieved December 29, 2015.
  15. ^ "Interactive Florida 2012 USDA Plant Zone Hardiness map". Plantmaps. Retrieved December 29, 2015.