The Monster Truck Madness rally at the L.A. County Fair really doesn't need much more of an explanation — there will be trucks, they will be approximately the size of monsters, and they will elicit delighted madness from fans of diesel fumes and crunching metal and comically aggressive names for vehicles. L.A. County Fair at the Pomona Fairplex, 1101 W. McKinley Ave., Pomona. 7:30 p.m. Thurs. $18.50-$22.50. http://www.lacountyfair.com.