The last cold blast could have been a colony killer. There is brood in the hive right now. The bees won't leave the brood, so starvation is a concern.
If the bees were alive last week a new check is a must because their status may have changed.
This blog is for beekeepers in Northern climates. I will be describing what I am doing with my bees on a monthly schedule. Copying any text or photos is forbidden except with written authorization of the author.