Hi Sabrina!
Many people try to guess what is the best time for a visit to
Walt Disney World but there is not a "right" answer. Obviously guests look at family school vacation times and generally those will be the more crowded for the parks. They will also look at weather which is important for many.
Coming from the northern lands you will find August a hot month in Florida. The temperatures will range on average from 73-92. The difference is that it is quite humid in Florida so that 92 will feel much warmer. The trick is to dress in light clothes, wear hats, take small fans, and stay hydrated. When you want to discuss rain it is still the rainy season there as well. But many guests just don't let that bother them. They bring small fold up umbrellas or ponchos and deal with the afternoon showers or storms. The parks often clear out a bit too if it rains so stay and enjoy shorter lines afterward. I always try to do any outdoor attractions early in the day as those will be the ones that will have to temporarily close due to weather.
Crowds will remain high the first two weeks of the month. Then schools will start up again and you will see a big drop in the attendance to the parks for the last two weeks right before the Labor Day weekend.
If August is the best time for you to visit then don't let the weather scare you away. Hit the parks early in the mornings and late in the evenings and enjoy the resort facilities such as the pools during the heat of the day. Disney also offers two great
Waterparks called Typhoon Lagoon and Blizzard Beach. These are wonderful places to cool off from the Florida heat!