United States Weather by Month
The United States is a vast and geographically diverse country that stretches across North America, bordered by Canada to the north, Mexico to the south, the Atlantic Ocean to the east, and the Pacific Ocean to the west. With an area of approximately 9.8 million square kilometers, the U.S. encompasses a wide range of landscapes, from towering mountain ranges like the Rockies and the Appalachians to flat plains, vast deserts, and extensive coastlines.
The U.S. can be broadly divided into five geographic and climatic regions:
- Northeast: Characterized by cold winters, warm summers, and significant seasonal variations. This region includes cities like New York, Boston, and Philadelphia.
- Midwest: Known for hot summers and cold, snowy winters. Cities like Chicago, Minneapolis, and Detroit experience significant temperature fluctuations.
- Southeast: This region has a humid subtropical climate, with hot summers and mild winters. Hurricanes are a concern in states like Florida, Georgia, and the Carolinas.
- Southwest: Featuring desert climates with scorching hot summers and mild winters, areas like Arizona, New Mexico, and parts of Texas often experience dry conditions.
- West: The western U.S. encompasses diverse climates, from the mild, Mediterranean-like climate of coastal California to the cold, mountainous regions of the Rockies and the Pacific Northwest.
Given the U.S.’s geographic diversity, weather patterns can vary drastically from one region to another. Below is a detailed breakdown of the weather in the U.S. month by month.
January
Weather Overview
January is the middle of winter across much of the United States, with cold temperatures and snow in many regions, particularly in the North and Midwest. The southern parts of the country tend to be more mild, though cold fronts can still affect these areas.
Northeast
- Temperature: -5°C to 5°C (23°F to 41°F)
- Weather: Cold and snowy. Major cities like New York and Boston frequently experience snowstorms and frigid temperatures.
Midwest
- Temperature: -10°C to 2°C (14°F to 36°F)
- Weather: Extremely cold with significant snowfall. Cities like Chicago and Minneapolis often experience sub-zero temperatures and blizzards.
Southeast
- Temperature: 5°C to 15°C (41°F to 59°F)
- Weather: Mild but occasionally chilly. Florida and Georgia are relatively warm, though the region can experience cold snaps.
Southwest
- Temperature: 10°C to 20°C (50°F to 68°F)
- Weather: Mild, with dry conditions in Arizona and New Mexico. Winter is a pleasant season here, ideal for outdoor activities.
West
- Temperature: 5°C to 15°C (41°F to 59°F)
- Weather: Varies greatly. Coastal California is mild and wet, while the Rocky Mountains and Sierra Nevada experience heavy snowfall.
February
Weather Overview
February continues to be cold across much of the U.S., especially in the northern regions, though some areas in the South and Southwest start to experience warming temperatures.
Northeast
- Temperature: -4°C to 7°C (25°F to 45°F)
- Weather: Cold, with frequent snowstorms. Boston, Philadelphia, and New York often see snow and freezing rain.
Midwest
- Temperature: -9°C to 3°C (16°F to 37°F)
- Weather: Very cold, with more snow. The Great Lakes region frequently experiences lake-effect snow, particularly in Michigan and Ohio.
Southeast
- Temperature: 7°C to 17°C (45°F to 63°F)
- Weather: Mild, with occasional cold fronts. Florida and Louisiana are relatively warm, but the northern parts of the Southeast can see frost.
Southwest
- Temperature: 12°C to 22°C (54°F to 72°F)
- Weather: Warm and dry in Phoenix and Tucson, with mild winter conditions continuing.
West
- Temperature: 5°C to 16°C (41°F to 61°F)
- Weather: Mild and wet along the Pacific coast, while the Rocky Mountains and Sierras continue to receive heavy snow.
March
Weather Overview
March signals the beginning of spring in many parts of the U.S., though winter conditions persist in the northern states. The South begins to warm up, and severe weather, including tornadoes, can start to form in the Southeast and Midwest.
Northeast
- Temperature: 0°C to 12°C (32°F to 54°F)
- Weather: Cold, but signs of spring begin to emerge. Snowstorms are still possible, especially in Maine and Vermont.
Midwest
- Temperature: -5°C to 10°C (23°F to 50°F)
- Weather: Cold but warming. Snow and rain alternate as winter gradually fades. Chicago and Minneapolis may still experience heavy snow.
Southeast
- Temperature: 10°C to 20°C (50°F to 68°F)
- Weather: Mild and increasingly warm, with the possibility of severe thunderstorms and tornadoes in states like Alabama and Mississippi.
Southwest
- Temperature: 15°C to 25°C (59°F to 77°F)
- Weather: Warm and dry. This is an ideal time for visiting Arizona and New Mexico, as the temperatures are comfortable.
West
- Temperature: 10°C to 18°C (50°F to 64°F)
- Weather: Coastal areas like San Francisco and Los Angeles experience mild, rainy weather, while higher elevations in the Rockies and Sierras remain snowy.
April
Weather Overview
April is full spring in much of the United States, with milder temperatures, blooming flowers, and more frequent rainfall. Tornadoes and severe storms become more common in the central and southern parts of the country.
Northeast
- Temperature: 5°C to 17°C (41°F to 63°F)
- Weather: Mild and rainy, with occasional snow in the far northern regions. Cities like New York and Boston see warmer temperatures and the start of spring blossoms.
Midwest
- Temperature: 2°C to 18°C (36°F to 64°F)
- Weather: Cool but warming. Rain becomes more frequent, and severe thunderstorms are possible, particularly in Iowa and Missouri.
Southeast
- Temperature: 15°C to 25°C (59°F to 77°F)
- Weather: Warm and humid, with frequent thunderstorms and the potential for tornadoes in Alabama and Tennessee.
Southwest
- Temperature: 20°C to 30°C (68°F to 86°F)
- Weather: Warm and dry, with ideal conditions for outdoor activities in Arizona and Nevada. Las Vegas experiences comfortable spring weather.
West
- Temperature: 12°C to 20°C (54°F to 68°F)
- Weather: Mild, with showers in California. The Pacific Northwest sees rainy weather, while the Rockies remain cooler with some lingering snow.
May
Weather Overview
May brings warmer weather across the U.S., with temperatures rising significantly in the South and Southwest. Severe weather, including tornadoes, is common in the Midwest and Southeast.
Northeast
- Temperature: 10°C to 22°C (50°F to 72°F)
- Weather: Mild and rainy, with increasing sunshine. New York and Philadelphia enjoy pleasant spring weather, while rain showers are still frequent.
Midwest
- Temperature: 8°C to 22°C (46°F to 72°F)
- Weather: Warm but stormy, with severe thunderstorms and tornadoes possible in Kansas, Nebraska, and Illinois.
Southeast
- Temperature: 18°C to 28°C (64°F to 82°F)
- Weather: Hot and humid, with thunderstorms and tornadoes becoming more frequent. Florida experiences summer-like conditions.
Southwest
- Temperature: 25°C to 35°C (77°F to 95°F)
- Weather: Very warm, with temperatures rising sharply in Phoenix and Las Vegas. Dry conditions prevail, with little to no rainfall.
West
- Temperature: 15°C to 25°C (59°F to 77°F)
- Weather: Mild and sunny, with California experiencing ideal weather. The Rocky Mountains start to thaw, and outdoor activities increase.
June
Weather Overview
June marks the beginning of summer in the United States, with hot temperatures in the South, Southwest, and Midwest. Severe weather continues in the central U.S., and the West experiences dry, warm conditions.
Northeast
- Temperature: 15°C to 27°C (59°F to 81°F)
- Weather: Warm and sunny, with occasional rain showers. New York and Boston experience pleasant summer weather.
Midwest
- Temperature: 15°C to 28°C (59°F to 82°F)
- Weather: Hot and stormy, with thunderstorms and tornadoes continuing in states like Oklahoma and Nebraska. The humidity increases significantly.
Southeast
- Temperature: 22°C to 32°C (72°F to 90°F)
- Weather: Hot and humid, with frequent thunderstorms in Georgia and Florida. Hurricane season officially begins, though major storms are rare in June.
Southwest
- Temperature: 30°C to 40°C (86°F to 104°F)
- Weather: Scorching hot, with dry conditions in Arizona and Nevada. Las Vegas and Phoenix experience extreme heat, and outdoor activities should be limited to early mornings or evenings.
West
- Temperature: 18°C to 28°C (64°F to 82°F)
- Weather: Mild and dry along the California coast, while inland areas experience hotter temperatures. The Pacific Northwest begins to warm up.
July
Weather Overview
July is typically the hottest month in the United States, with scorching temperatures across the South and Southwest. Humidity levels are high in the Southeast, and the risk of hurricanes begins to increase.
Northeast
- Temperature: 18°C to 30°C (64°F to 86°F)
- Weather: Hot and humid, with occasional thunderstorms. Cities like Philadelphia and Washington, D.C. experience typical summer heat and humidity.
Midwest
- Temperature: 18°C to 32°C (64°F to 90°F)
- Weather: Hot and humid, with thunderstorms and tornadoes continuing in the central U.S. Chicago and St. Louis experience hot, muggy conditions.
Southeast
- Temperature: 25°C to 35°C (77°F to 95°F)
- Weather: Hot, humid, and stormy. Thunderstorms are frequent, and hurricane activity begins to increase in Florida and the Gulf Coast.
Southwest
- Temperature: 35°C to 45°C (95°F to 113°F)
- Weather: Extremely hot and dry. Phoenix and Las Vegas experience dangerous heat, with temperatures soaring above 110°F (43°C). Monsoon rains can bring isolated thunderstorms to Arizona and New Mexico.
West
- Temperature: 20°C to 30°C (68°F to 86°F)
- Weather: Warm and dry along the California coast, while inland areas like Sacramento and Reno experience high temperatures. The Pacific Northwest enjoys mild and sunny weather.
August
Weather Overview
August remains one of the hottest months in the U.S., particularly in the South, Southwest, and Midwest. The hurricane season intensifies, and the risk of storms in the Southeast increases.
Northeast
- Temperature: 17°C to 30°C (63°F to 86°F)
- Weather: Hot and humid, with thunderstorms common in New York and Boston. Heatwaves are possible, and rain is frequent.
Midwest
- Temperature: 18°C to 32°C (64°F to 90°F)
- Weather: Hot and humid, with severe thunderstorms still possible in Indiana and Illinois. Tornadoes may occur, though they are less common than earlier in the year.
Southeast
- Temperature: 24°C to 34°C (75°F to 93°F)
- Weather: Hot and humid, with frequent thunderstorms. Hurricane season peaks in August, and coastal areas like Florida and Louisiana are at risk of tropical storms.
Southwest
- Temperature: 33°C to 45°C (91°F to 113°F)
- Weather: Extremely hot and dry. Las Vegas and Phoenix continue to experience extreme heat, though isolated thunderstorms from the monsoon season may provide brief relief.
West
- Temperature: 18°C to 30°C (64°F to 86°F)
- Weather: Warm and dry along the coast, with inland areas like California’s Central Valley experiencing high temperatures. The Pacific Northwest remains mild, with occasional rain.
September
Weather Overview
September marks the beginning of fall, with cooling temperatures in the North and Midwest. The hurricane season is at its peak, with the Southeast facing the highest risk of tropical storms.
Northeast
- Temperature: 12°C to 25°C (54°F to 77°F)
- Weather: Cooler temperatures, especially in the northern regions like Maine and Vermont. New York and Boston experience milder conditions, with fewer thunderstorms.
Midwest
- Temperature: 10°C to 25°C (50°F to 77°F)
- Weather: Cooler and less humid, with pleasant temperatures across the Great Lakes region. Rain is less frequent, and tornado activity decreases.
Southeast
- Temperature: 20°C to 30°C (68°F to 86°F)
- Weather: Warm and humid, with frequent thunderstorms. The hurricane season reaches its peak, with a high risk of storms in Florida and along the Gulf Coast.
Southwest
- Temperature: 28°C to 38°C (82°F to 100°F)
- Weather: Hot, though temperatures begin to drop slightly. The monsoon season brings thunderstorms to Arizona and New Mexico, providing some relief from the heat.
West
- Temperature: 15°C to 25°C (59°F to 77°F)
- Weather: Mild and dry along the California coast, while inland areas like Nevada and Utah remain warm. The Pacific Northwest experiences cooler, rainy weather.
October
Weather Overview
October brings cooler fall temperatures to much of the U.S. The hurricane season begins to wind down, and the northern states experience the first frost and occasional snow.
Northeast
- Temperature: 5°C to 18°C (41°F to 64°F)
- Weather: Cool, with fall foliage at its peak in New England. New York and Boston experience chilly nights and occasional rain.
Midwest
- Temperature: 5°C to 18°C (41°F to 64°F)
- Weather: Cool and crisp, with frost likely in northern states like Minnesota and Wisconsin. Rain and occasional snow are possible.
Southeast
- Temperature: 15°C to 25°C (59°F to 77°F)
- Weather: Warm and humid, with the potential for late-season hurricanes. Florida and Georgia remain relatively warm.
Southwest
- Temperature: 20°C to 30°C (68°F to 86°F)
- Weather: Warm and dry, with temperatures dropping significantly compared to summer. Arizona and Nevada experience pleasant fall weather.
West
- Temperature: 12°C to 22°C (54°F to 72°F)
- Weather: Mild and dry in California, while the Pacific Northwest experiences cooler, rainy conditions.
November
Weather Overview
November is the start of winter in the northern U.S., with colder temperatures and increasing snowfall. The South remains mild, though temperatures begin to drop.
Northeast
- Temperature: 0°C to 12°C (32°F to 54°F)
- Weather: Cold, with the first snowfalls of the season in New York and Boston. Rain is frequent, and frost is common in the northern regions.
Midwest
- Temperature: -5°C to 10°C (23°F to 50°F)
- Weather: Cold, with snow likely in states like Michigan and Minnesota. Rain and freezing rain are also common.
Southeast
- Temperature: 10°C to 20°C (50°F to 68°F)
- Weather: Mild, with cooler temperatures and less humidity. Florida and Louisiana remain relatively warm, though the risk of tropical storms decreases.
Southwest
- Temperature: 15°C to 25°C (59°F to 77°F)
- Weather: Warm and dry, with pleasant conditions in Arizona and New Mexico. This is an ideal time for outdoor activities.
West
- Temperature: 8°C to 18°C (46°F to 64°F)
- Weather: Cool and wet in the Pacific Northwest, with increasing rain. California experiences mild weather, though rain is more frequent in the north.
December
Weather Overview
December marks the start of winter across much of the U.S., with cold temperatures and snow in the northern regions. The South remains mild, but colder air masses occasionally bring cooler temperatures.
Northeast
- Temperature: -5°C to 8°C (23°F to 46°F)
- Weather: Cold, with frequent snow in New York and Boston. Winter storms are common, particularly in the northern parts of the region.
Midwest
- Temperature: -10°C to 5°C (14°F to 41°F)
- Weather: Extremely cold, with snowstorms and freezing temperatures. Chicago and Minneapolis experience sub-zero temperatures and heavy snowfall.
Southeast
- Temperature: 5°C to 15°C (41°F to 59°F)
- Weather: Mild but occasionally chilly. Florida and the Gulf Coast remain relatively warm, though frost is possible in the northern areas.
Southwest
- Temperature: 10°C to 20°C (50°F to 68°F)
- Weather: Mild, with dry conditions in Arizona and New Mexico. Winter is a pleasant season, with comfortable daytime temperatures.
West
- Temperature: 5°C to 15°C (41°F to 59°F)
- Weather: Varies greatly. Coastal California is mild and wet, while the Rocky Mountains and Sierra Nevada experience heavy snowfall.
