Does an atypical mole usually turn into melanoma?

Atypical nevi. Atypical moles(nevi), prescancerous nevi, dysplastic nevi are classified as mild, moderate and severe. After severe is melanoma. It is believed than normal moles go through this progression to become a melanoma. Thus, skin screening is important to pick up the precancerous nevi before they turn into melanoma.
No. Atypical moles may already be melanomas. If you have atypical appearing moles that are irregular in shape, color and size, go see a dermatologist to have them checked for melanoma or other types of skin cancer.