It doesn't matter if you are from Australia or Zimbabwe - Iowa weather is going to be a lot different than your home country. The Midwest section of the United States is famous for its extreme (and rapidly changing) weather. You will need to bring clothing for all seasons - from hot and steamy to cold and windy.
When you arrive in Iowa, it is likely to be very hot. If your room is not air conditioned, you should buy or borrow a fan. If you are unaccustomed to really hot, humid weather, be sure to drink plenty of water during exercise or outdoor activities. The combination of heat and humidity can make an 85-degree day seem well over 100 degrees. Take frequent breaks and rest in a shady place. You should also wear sunscreen if you are worried about getting sunburn.
The weather will start cooling off late in September; the days may stay fairly warm but the nights will be chilly. The leaves on the trees will start to change color, making our campus and community a very pretty place. Some people say this is their favorite time of year!
The days and nights will get significantly colder in November and December. It is very important that you dress appropriately for the weather. Do not rely on observing what other students wear - some of them go out of doors in sandals, even when there is snow on the ground. Wear what is comfortable (and sensible) for the conditions.
Students from countries with a warm climate often ask "How cold does it really get?" It's hard to believe that cold weather can be dangerous, but below-zero temperatures combined with strong winds can affect the "wind chill factor". A crisp, 20-degree day can actually feel almost 16 degrees colder, combined with a 20-mile per hour wind. During periods of extreme cold, you should wear a warm coat and cover all exposed skin. Hats, gloves and scarves are a necessity, along with a pair of sturdy boots.(Sometimes ice and snow can make walking a little tricky.) When the weather is bitterly cold with wind chills below zero, frostbite can occur in a matter of minutes. And snow? We usually don't get significant snowfall until later in the season (February is actually our snowiest month).
Springtime in Iowa is hard to predict: it's possible to have a 70-degree day in March, followed by a heavy snow the next day! Once the weather has warmed up, especially during the month of May, we become more alert to the possibility of severe thunderstorms or tornadoes. If a tornado warning is in effect a siren will sound. Rather than going outside to observe conditions, seek immediate shelter in the lowest level of the building you are in. The residence hall staff will explain emergency procedures for your building. Midwest storms are fascinating but deadly - they can form quickly with little warning and may be accompanied by strong winds, hail, heavy downpours of rain and lightning. If you feel compelled to witness a thunderstorm, do it from the safety of a room inside a building, away from windows. Never try to watch or chase a tornado.
If you do not own appropriate clothing for the weather in Iowa, or if you don’t want to pack bulky coats and boots, you will have the opportunity to purchase these items inexpensively after you arrive.