It can be as there is not a lot of shade
I went last Saturday and the weather was great, a nice breeze and not too hot at all. But most years I go around the last weekend of the faire and its very hot. They did have an escape room with AC tho if you like to play those for $20.
Check out the weather for the day. You can always stay cool with drinking ice water or slushy drinks.
Yes, if you live closer to the coast, the heat at the fair grounds might surprise you. Good idea to check the weather in Baldwin Park first.
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