The great geographical and cultural diversity of the USA means that it's any time if a good time to visit. Whether you're into blues music or bluebonnets, craggy mountain peaks or dense redwood forests, world-class theater or wide open spaces, the United States will have something for everyone.
Although summer is usually considered high season and winter the low season, that largely depends on the seasonal draws found in each region. If you seek out the shoulder months, either in the fall or early spring, you'll find good deals, fewer crowds, and milder weather.
But winter may secretly be the best time to visit the USA. In the south, temperatures are comfortable for daytime hiking in desert terrain and Florida's amusement parks are popular when school is out. Winter in the north sees snow making cityscapes magical and Christmas decorations to write home about.

Low Season: November to March
Best for budget travelers and exploring quiet museums
For much of the United States, the winter months (November to March) bring cold days, snowfall in the north and heavier rain some regions.
The US is famous for its commitment to holiday displays, from Halloween to New Year's Day via the Day of the Dead, Thanksgiving, and Christmas, shops, markets and town centers are awash with color and decoration over this season. Christmas trees and sparkling lights also add some a festive atmosphere to most of the country in deep winter.
Aside from the days between Christmas and New Year travelers can expect most major tourist sites to be largely free of crowds over the cooler months. For visitors traveling on a budget, winter sees the lowest prices for accommodation (except at ski resorts and "winter sun" getaway destinations like Florida).
Shoulder Season: September to November, April to May
Best for spring and fall colors and getting outdoors
Although the shoulder season sees fewer crowds, spring flowers (April) and fiery autumn colors (October) appear in many parts of the country and make visiting during this time a special treat. Consider traveling to New England for fall, when autumn colors are at their peak. For spring wildflowers, the mountainous western states are a popular sight, as well as Texas Hill Country or Smoky Mountains National Park.
Travelers during the shoulder season should be able to find deals on car rental and accommodation with a bit of searching.
High Season: June to August
Best for festivals and getting a tan
With a country as large as the United States, variations in temperature and weather are to be expected. Generally, the summer months of June through August see high temperatures. With schools out, expect large crowds at major attractions and popular national parks. In ski-resort areas, January to March is high season.
With high popularity comes high accommodation rates. Budget travelers should look outside of major metro areas to find a deal during high season.

Month-by-month breakdown
Here's a monthly guide to what you can expect through the year in the USA. All events are subject to change.
January
The New Year starts off with a shiver, as snowfall blankets large swaths of the country. Ski resorts kick into high gear, while sun lovers seek refuge in warmer climes (especially Florida).
Key events: Mummers Parade, Chinese New Year, Sundance Film Festival
February
Unless they're on a mountain getaway, most Americans dread February's long dark nights and frozen days. For foreign visitors, this can be the cheapest time to travel, with discounted rates for flights and hotels.
Key events: Mardi Gras
March
The first blossoms of spring arrive (at least in the south – the north still shivers in the chill). In the mountains, it's still high season for skiing. Meanwhile, drunken spring breakers descend on Florida.
Key events: St Patricks Day, National Cherry Blossom Festival, South by Southwest
April
The weather is warming up, though in the north April can still be unpredictable, bringing chilly weather mixed with a few teasingly warm days. Down south, it's a fine time to travel.
Key events: Fiesta San Antonio, Jazz Fest, Juke Joint Festival, Patriots' Day, Gathering of Nations
May
May is true spring and one of the loveliest times to travel, with blooming wildflowers and generally mild sunny weather. Summer crowds and high prices have yet to arrive.
Key events: Beale Street Music Festival, Cinco de Mayo

June
Summer is here. Americans spend more time at outdoor cafes and restaurants, and head to the shore or to national parks. School is out; vacationers fill the highways and resorts, bringing higher prices.
Key events: Bonnaroo Music & Arts Festival, Gay Pride, Chicago Blues Festival, Mermaid Parade, CMA Music Festival, Telluride Bluegrass Festival, Tanglewood Musical Festival
July
With summer in full swing, Americans break out the backyard barbecues or head for the beach. The prices are high and the crowds can be fierce, but it's one of the liveliest times to visit.
Key events: Independence Day, Oregon Brewers Festival, Pageant of the Masters, Newport Folk Festival
August
Expect blasting heat in August, with temperatures and humidity less bearable the further south you go. You'll find people-packed beaches, high prices and empty cities on weekends, when residents escape to the nearest waterfront.
Key events: Lollapalooza, Iowa State Fair

September
With the end of summer, cooler days arrive, making for pleasant outings nationwide. The kids are back in school, and concert halls, gallery spaces and performing-arts venues kick off a new season.
Key events: Santa Fe Fiesta, Burning Man Festival
October
Temperatures are falling, as autumn brings fiery colors to northern climes. It's high season where the leaves are most brilliant (New England); elsewhere expect lower prices and fewer crowds.
Key events: New York Film Festival, Fantasy Fest, Halloween
November
No matter where you go, this is generally low season, with cold winds discouraging visitors despite lower prices (although airfares skyrocket around Thanksgiving). There's much happening culturally in the USA's big cities.
Key events: Thanksgiving

December
Winter arrives as ski season kicks off in the Rockies (out east, conditions aren't usually ideal until January). Aside from winter sports, December means heading inside and curling up by the fire.
Key events: Art Basel, New Year's Eve
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