The USDA offers an amazing plant Hardiness zone Map on the National Arboretum website that will help identify your climate, and the last frost date. You can find your zone by simply clicking the image of the map posted below. Once the National Arboretum website is loaded, select your state and read the key listed on that page.
Remember some vegetables can be started earlier in the year than others. The zone in your area reflects different climatic changes. To give you a better ideal on what crops are suitable for what climate, here a few different types of crops and the growing season they are most suitable for:
Some Frost-tolerant crops are: Kale, lettuce, carrots, onions, potatoes, radishes, broccoli, cauliflower
Some Warmer-season crops are: Tomatoes, peppers, cucumbers, melons, corn, summer squash
Some Cool-Season crops: Spinach, carrots, broccoli, cauliflower, kale, lettuce
I also suggest these resources in helping determine your growing climate: