Experts and BHG readers answer.
Tilling time will vary from year to year depending on the weather. Tilling when it's too wet can damage the soil structure, so soil moisture is your main concern. Do a quick soil-moisture test to determine if it's a good time to till. Take a handful of soil and squeeze it. Then see if it crumbles easily when you open your hand or if it stays in a moist clump. If it crumbles, you can till. If it stays in a clump it's too moist to work in, so give it another sunny day and then test again.