Pretty accurate. Sunny, muggy in the morning with the afternoon storms, then rain deminishing in the evening.
Think of it as an opportunity: the parks can thin out quite a bit when the storms roll thru, so if you stick it out or take a midday break and return (if you're staying at a Disney resort) just after the storms are ending, you can still manage a good day. Play by ear and have a plan each day when you wake up and see that days weather forecast.
Advice: buy ponchos at home and bring with you. The ones in the park are expensive!