In the event you arrive at the airport without valid identification, because it is lost or forgotten, you may still be allowed to fly. The TSA officer may ask you to complete a form to include your name and current address, and may ask additional questions to confirm your identity. If your identity is confirmed, you will be allowed to enter the screening checkpoint. You may be subject to additional screening.
You will not be allowed to fly if your identity cannot be confirmed, you chose to not provide proper identification or you decline to cooperate with the identity verification process.
TSA recommends you to arrive at least two hours in advance of your flight time to allow ample time for security screening and boarding the aircraft.