Tornado card A4: third level of tornado card set. This card cautions the caller to use overpasses as a last resort for protection. For smaller tornadoes (F0-F2) overpasses can offer some protection, especially when the caller can wedge up into a small space where the dirt birm meets the girders of the overpass. However, much can go wrong! If the tornado is F3 or greater there is a good chance that large pieces of dangerous debris will accumulate under the overpass and arrive at very high speed. The caller could be injured or killed by debris. Also, many overpasses have brick abutments that don't offer safe haven and may actually accelerate wind flow. A third reason for not choosing overpasses is that large numbers of cars stopping on the highway can block emergency vehicles.

In rural areas when the caller can clearly see the tornado's location and direction of movement it often makes more sense to simply avoid the tornado if there are roads available to do so. Most people will not follow advice that has them taking actions that don't seem to make sense or are uncomfortable such as abandoning their car and climbing into the ditch.