Under the Gray Skies by Jacqueline Druga

A long awaited sisters vacation hits a slight bump in the road when a series of tremors instantly cause the cancellation of all flights. Believing the airport is not the safest place, Lacey and her sister hurry from the terminal and board a crowded tram. Then it happens. No one knows why, how or what occurs. Cities are decimated, oceans rise and people drop dead from the cataclysmic event. The world becomes a dark place on a fast track to the next ice age. Lacey somehow survives and finds herself in a city of rubble. Unaware that it was a global event, she treks from the destruction in an attempt to find help. Along the way she meets Madison. Both women are far from home and together they embark on a mission to find their families thousands of miles away. The country is in chaos and is fast becoming uninhabitable. It is a race against the clock as the world grows colder and more dangerous by the day. Lacey and Madison vow not to give up until they know what has happened to those they love.