That depends on the size of the storm and the number of people who evacuate. the chart on the reverse side will give you an idea, but keep in mind the times shown are only estimates. They assume that all evacuation routes are open and only show the time needed to move all traffic inland just beyond the threatened risk areas. It will take longer to reach a shelter location or your final destination.
Also, keep in mind, if the chart shows 10 hours, officials won't wait until the storm is 10 hours from landfall to begin an evacuation. Remember, the goal is to get everyone out of the threatened area before evacuation routes become impassable or unsafe due to flooding or high winds. This will happen when the storm is still many hours away from landfall. So, don't be surprised if there are no clouds and the sun is shining when local officials tell you to evacuate. Follow their instructions; your health and safety are their main concern.