Knowing the dew point can be helpful in determining how humid the outside air will feel. A dew point greater than 70 degrees Fahrenheit is oppressive. This means the air is holding an incredible amount of moisture. So, you're likely to sweat even without any physical exertion. A dew point greater than 55 degrees Fahrenheit means the air is merely moist. However, you'll still feel sticky, even if you don't sweat. A dew point below 55 degrees Fahrenheit tends to feel most comfortable. The air is dry, with very low moisture content.

Warmer air can hold more moisture. In an environment where the outside temperature is hot (80°F) and the dew point is high (60°F), we find it difficult to stay cool. Instead, we feel sweaty and uncomfortable.

The National Oceanic and Atmospheric Administration (NOAA) records climatic data throughout the United States. So, it's possible to extrapolate weather trends with NOAA data. In fact, WeatherOps used NOAA data to rank U.S. cities based on which had the most number of days at temperatures greater than 85 degrees Fahrenheit and average dew points greater than 65 degrees Fahrenheit. Don't sweat, however. There are plenty of ways to stay cool, even in the five most humid U.S. cities.

Corpus Christi, TX

Credit: DenisTangneyJr/ iStock

When the temperature rises at Corpus Christi, keep your cool aboard the USS Lexington aircraft carrier. One of the city's most popular attractions, the USS Lexington offers visitors five, self-guided tours for exploring its eleven decks. The ship has interactive displays and a Pearl Harbor exhibit.

Additionally, knowledgeable volunteers are available to answer your questions. For a modern take on the naval experience, check out any of the USS Lexington's attractions such as the virtual battle station, flight simulator, or escape room. To prevent from historical overload, take a walk along Corpus Christi's magnificent, 2-mile long Bayfront Seawall. You may also enjoy the S.E.A. District downtown, where Corpus Christi's sports, entertainment, and art scenes flourish.

For scenes of solitude, visit Padre Island National Seashore, the longest stretch of undeveloped barrier island in the world. The island separates the Gulf of Mexico from the Laguna Madre, only one of several global hyper-saline lagoons. Padre Island is the site of numerous Spanish wrecks and also a nesting ground for Kemp's Ridley sea turtles.

West Palm Beach, FL

Credit: Sean-Pavone/ iStock

Enjoy contemporary America at its best at West Palm Beach, Florida's cultural center. The Norton Museum highlights contemporary exhibits and photography by American, Chinese, and European artists. Meanwhile, the Cornell Art Museum displays intriguing pieces at nearby Old School Square.

You can also attend theater shows, lectures and exhibitions in other buildings on the Old School Square campus. The history buff will appreciate the flamboyant Flagler Museum, which showcases artifacts from America's Gilded Age.

Looking for more outdoor activities? Return to nature on Peanut Island, where you can spend the day basking in the sea breeze in tropical surroundings. Camping is welcome here and is the perfect respite from the heat.

Fort Myers, FL

Credit: benedek/ iStock

No doubt, the beach is one of the main attractions in the tropics. Fort Myers is no exception. However, when the humidity hits, one of the best ways to keep cool is to take a boat ride to one of several nearby islands. Sanibel and Captiva islands boast soothing spas, tantalizing restaurants, and the historic Ford and Edison winter estates. Beachcombers will enjoy looking for sea treasures along Sanibel's sprawling beach front, considered the best shelling location in North America.

That's not all. The unspoiled beaches and thriving waters at Cayo Costa State Park beckon all but the most jaded tourist. Here, you'll want to keep a look out for an array of shore-side and marine wildlife along nine-miles of pristine paradise. Who knows? You may be able to spot dolphins and manatees, as well.

Miami, FL

Credit: Art-Wager/ iStock

When South Beach heats up, there are plenty of ways to keep cool in Miami. Start by touring the exquisite Vizcaya Museum, an eighteenth-century Italian style villa that will sweep you off your feet. The villa's formal gardens provide a tranquil setting for tired minds. For a more lively scene, visit Miami's Art Deco District, where you can explore a square mile of MiMo (Miami Modern) architecture amidst an Atlantic Ocean backdrop. The 800-plus buildings in the MiMo district make up the world's first 20th century historic district.

Outdoor enthusiasts will want to check out the Everglades National Park. Here, you can take an exhilarating air-boat tour, relaxed kayak paddle, or leisurely walk along palm shaded boardwalks. You'll want to keep a keen eye out for alligators, however.

Brownsville, TX

Credit: Denis-Tangney-Jr/ iStock

Brownsville is the largest city in Southern Texas' Rio Grande Valley. Here, you can escape the humidity by immersing yourself in Brownsville's history. Step onto the Palo Alto Battlefield, the first major battle site of the U.S.–Mexican War. The two-year U.S.–Mexican War basically changed America's map.

Historical museums throughout the city provide fascinating facts related to Brownsville's prominent role during the Civil War and later, when the city became an established trade center. Due to Brownsville's location on the Rio Grande, the city was once a bustling steamboat hub.

If you prefer the outdoors, dip your toes into the refreshing waters of the Gulf of Mexico as you stroll along secluded, white sand dunes at Boca Chica Beach.