Fire Mountain by Dana Mentink

Fire rains from above as they fight to discover the truth and stay alive.

In the shadow of a threatening volcano, long-haul trucker Kit Garrido wakes up in her crashed big rig, unable to recall what happened or why she’s suddenly in possession of someone’s baby. Fiercely independent, she has to admit that perhaps this time she could use a little help.
As the threat of eruption grows, former cop Cullen Landry refuses to leave his cabin in the evacuation area, which is why he’s the only one left who can help Kit escape the crumpled cab of her truck. He doesn’t want to get tangled up in the mystery of the beautiful woman with an abandoned infant, but when he sees the bullet hole in the windshield and the bloody handprint on the interior, he realizes that he’s in this thing, like it or not. When two armed men with ill intent approach, the race is on to stay alive, discover the truth, and find the baby’s missing mother—all while a deadly mountain rains fire from above.