Processing times vary from state to state. Many are taking up to 90 days or longer to process returns and issue refunds. This is mainly due to a lot of states implementing additional safeguards to prevent fraud.
You can go here State Refund Processing Timeframe and check to see if your state is listed with processing time. Most have notated on their Where's My Refund tracking page that they are delaying processing or that it may be longer this year in comparison to prior years.