Motorists are urged to keep an eye out for pavement “blowups”, the summer’s version of potholes, created by a combination of moisture and weakening pavement when temperatures consistently reach 90 degrees or more.

The Missouri Department of Transportation (MODOT) says a blowup on southbound I-35 Tuesday night caused the closure of the on ramp to SB I-35 from Pleasant Valley Road until repairs can be made.

Pavement blowups are fractures occurring when a roadway surface expands at a crack or joint into which moisture has seeped. That crack weakens the pavement, and the heat causes the roadway to buckle and warp, creating holes in the surface. But despite the term, the pavement does not actually explode.

Motorists encountering pavement blowups should call (888) ASK MODOT (275-6636).