Houston experiences a humid subtropical climate (Köppen climate classification Cfa), influenced by its proximity to the Gulf of Mexico and low elevation. The city's climate is characterized by hot, humid summers and mild winters.
Temperature patterns The city exhibits distinct seasonal temperature variations throughout the year. August represents the peak of Houston's summer season, with average temperatures reaching , making it the warmest month annually. Conversely, January marks the coolest month, with average high temperatures of , representing the city's winter season.
Seasonal characteristics Houston's subtropical climate produces hot, humid conditions during summer months, while winter temperatures remain relatively mild compared to northern latitudes. The city's location along the Gulf Coast moderates extreme temperature fluctuations and contributes to year-round humidity levels.
Seasonal observation
While Houston's yearly temperature cycles follow four distinct seasons, weather-wise, the city has a rainy season and a dry season. The wet season lasts from April/May to September/October; the dry season lasts from November/December to March/April. However, during El Niño or La Niña years, the wet and dry seasons can often either last longer than usual or be delayed.
Summer
June through August are very hot and humid, often with scattered afternoon showers and thunderstorms. At George Bush Intercontinental Airport (IAH), the normal daily high temperature peaks at on August 5–12,NOAA 1981-2010 normals with a normal of 102.4 days per year at or above and 3.5 days per year at or above . The average relative humidity ranges from over 90 percent in the morning to around 60 percent in the afternoon.Department of Meteorology at the University of Utah. National Relative Humidity. Retrieved on 2007-03-10. Summer temperatures in Houston are very similar to average temperatures seen in tropical climates, such as in the Philippines and the lower elevations of Central America. The value of relative humidity results in a heat index higher than the actual temperature.Your Florida Backyard. The Heat Index. Retrieved on 2008-03-20. The highest temperature ever recorded at George Bush Intercontinental Airport was on four occasions: September 4, 2000;Weather Underground. History for Houston Intercontinental, Texas on Monday, September 4, 2000. Retrieved on 2007-03-10. August 27, 2011; August 24, 2023; and August 27, 2023. On June 29, 2013, the temperature at George Bush Intercontinental Airport reached , the highest ever recorded in June. Heat stroke can strike people who stay outdoors for long periods of time during the summer, making hydration essential for outdoor work and recreational activity.Texas Medical Center News. Temperature Rising? Could be Heat Stroke. Retrieved on 2007-03-11. The 2014 summer season did not yield + degree weather in response to the monsoon-sequel rainfall during late June to August, during a period where the Pacific Coast off Central America was heating up, which evolved into the 2014–16 El Niño event - this cycle was also observed between 1971 and 1976, during post-El Nino intervals.
The Old House Web How Air Conditioning Changed America. Retrieved on 2007-03-11. Because of the high temperatures that persist from April through October, most indoor workers in Houston spend the hottest part of the day in an air-conditioned environment. After World War II, air conditioning stimulated the growth of Houston, and it was called the most air-conditioned city in the world in 1950.Houston Geological Auxiliary. A Short History. Retrieved on 2014-02-04.
Autumn Autumn in Houston is warm, with temperatures averaging in the upper 60s to lower 80s °F (20-28 °C) during the day and in the 40s to lower 60s °F (10-17 °C) at night.Greater Houston Partnership. Information/Data — All About Houston. Retrieved on 2006-01-09. Cool fronts that move through the region during the fall can bring rain. Hurricanes can move into the area from the Gulf of Mexico, bringing heavy rains and high winds. However, most years see little or no significant hurricane activity. Flooding most frequently occurs in October and November, which is the end of the Southeast Texas wet season.Weather Research Center. Significant Houston Area Floods. Most of these flood events result from remnants of Eastern Pacific cyclones interacting with upper-level boundaries; October 2015 was the latest example of such an occurrence, wherein the remnants of Hurricane Patricia brought over 9 inches of rain to the city.Reuters. Retrieved on 2006-01-09. The latest hurricane to reach Texas was Hurricane Beryl in July 2024.
Winter Winters in Houston are mild, dry, and temperate compared to most areas of the United States. Houston winters are, on average, slightly colder than South Florida and Southern California, on par with southern Louisiana and Central Florida, but much warmer than Dallas, Atlanta, San Antonio, Austin, and other inland southern cities. The average high in January, the coldest month, is 62.9 °F (17.2 °C) and the low is 43.2 °F (6.2 °C). George Bush Intercontinental Airport sees an average of 9.6 days per year of freezing temperatures. Cold fronts during the winter can bring nighttime lows that drop into the 30s but usually remain above freezing. The coldest weather of the season often involves temperatures in the low 30s to mid-40s at night. Hard freezes are not uncommon in North Houston; George Bush Intercontinental Airport has recorded at least one freeze every winter since it opened in 1969, except for 2023, when the lowest was 33 degrees. However, areas in the central and southern parts of the Houston metro area are consistently several degrees warmer on the coldest winter nights. Areas south of Interstate 10 can have entire winters without a freeze. The coldest temperature ever recorded at George Bush Intercontinental Airport was 7 °F (−14 °C) on December 23, 1989. Elsewhere, the temperature in Houston dropped to 5 °F (−15 °C) on January 18, 1930. The record low at Houston's Hobby Airport, closer to the city, is 9 °F (−13 °C).
In December, southward-moving cold fronts TSHA Handbook of Texas. Blue Norther. Retrieved on 2007-03-11. can bring cold rain, low wind chills, and, rarely, frozen precipitation. Early January is the coldest time of the year, with temperatures moderating slightly by February. Winter is also the driest part of the year for Houston.
Spring Spring comes with a gradual warm-up from winter, lasting from February through May. Temperatures are generally not hot yet, averaging from in the day and at night. Spring thunderstorms are common, often with spectacular lightning shows.Severe Thunderstorms. National Weather Service Forecast Office Houston/Galveston, Texas, Retrieved on March 11, 2007 This rainfall prompts Houston's 10-month-long "growing season" to begin. March sees the return of many types of insects, including butterflies and mosquitoes, to Houston's warm climate.
Precipitation Rainfall is the most common form of precipitation in Houston and is plentiful throughout the year. The wettest month is June, with an average of of rain. The city (and much of South and Southeast Texas) has its own irregular monsoon season, which usually lasts from May to October, but sometimes from April to September. Houston normally receives of precipitation on 104.0 days annually. The most precipitation to fall in one year was , which occurred in 1979. Total rainfall in 2017, the year of Hurricane Harvey at IAH in northern Houston, was ; rainfall in the month of the storm, August 2017, at IAH totalled .
Houston has received less than of rain only once: in 1917.Houston's Annual Top 10 List. National Weather Service, Houston/Galveston, Texas. January 30, 2006. Last accessed January 3, 2006. In 2011, a drought resulted in a total of , with less than recorded at IAH in six of the year's 12 months; only was recorded that August and that April.
Flash flood warnings are common all year, and due to the flat landscape, heavy rains often threaten life and property in the city. Sea breeze showers which are monsoon-like (especially during the summer months, originating from the mesoscale convective cycle, where the polar jet stream usually forms an omega block) are common throughout the Texas Gulf Coast area (from Brownsville to the Florida Peninsula), which has a similar climate to areas like Mumbai and Kolkata – locals refer to the sea breeze showers as the Gulf Coast Monsoon (also called the Gulf of Mexico or the Texas Monsoon), despite Houston being above sea level. The sea breeze showers are also a contributor to the North American Monsoon.
Sleet and freezing rain are more common than snow in the Houston area. While accumulating snow events are rare in Houston, brief snow flurries occur every winter in the greater Houston area. These usually have no impact on travel as they are light, brief, and isolated. Hail can accumulate, but only in small quantities.
Extreme weather Houston has occasional severe weather, mostly flooding. Hurricanes that have the potential to landfall bring severe damage to the area. Seven major hurricanes have hit the Galveston and Houston areas in the past 100 years. Four have done significant damage to Houston.
Hurricanes and tropical storms Because Houston is on the Gulf of Mexico, the city has a high chance of being hit by hurricanes or tropical storms every hurricane season (June through November).
In 1837, the Racer's Storm passed just to the south of the town, raising water levels four feet.http://www.srh.noaa.gov/lch/research/txearly19hur.php Early Texas Hurricane History, 1800-1850, Retrieved on March 10, 2007 The Great Hurricane of 1900 destroyed the nearby (and then much bigger) city of Galveston, which is situated on a barrier island southeast of downtown Houston. That hurricane weakened to a tropical storm by the time it reached Houston.Remembering the Great Hurricane, September 8, 1900 . Galveston County Daily News, Retrieved on March 11, 2007 The periphery of Hurricane Carla hit the city in 1961, causing major damage to Houston. At the time of landfall, Carla was the most powerful tropical system to hit the Texas coast in over 40 years.Hurricane Carla, September 9-12, 1961. National Weather Service, Retrieved on March 11, 2007 In 1983, the city was struck squarely by Hurricane Alicia, causing $1 billion of damage to the city during a down period in the city's economy.
Tropical Storm Allison dumped up to of rain on parts of the city over a five-day period in 2001, and was the most destructive and costly natural disaster in Houston history Tropical Storm Allison Floods June 5-9, 2001. National Weather Service Forecast Office Houston/Galveston, Texas, Retrieved on March 11, 2007 prior to Hurricane Harvey. Area flooding was catastrophic and widespread. The storm completely overwhelmed the flood control system and caused 22 deaths in Houston and $6.05 billion (2006 USD) in damage. It was the only tropical storm in history to have its name retired until Tropical Storm Erika in Dominica in 2015.
Tropical Storm Erin made landfall in August 2007 with heavy rainfall. A total of of rain fell elsewhere than George Bush Intercontinental Airport on August 16, and many roads and neighborhoods were flooded. Metropolitan Transit Authority of Harris County, Texas, halted its light rail and bus services in view of the effects. Four deaths in the city were attributed to the storm. The Houston Fire Department reported 72 rescue operations.