I just went yesterday, the heat was bad but the crowd wasnt bad at all. But i wasnt happy with the park.
Weather wise it should be mid to high 90s. As far as crowds go most LA/OC schools should be getting back in session so it should help with that.
From june to September the parks are pretty busy. But one of the great things is that they close later during that time. I recommend going and getting fast passes for rides with long lines like space mountain and splash mountain. Overall a very fun experience so definetly go.
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