It's going to be brutally cold overnight into Saturday. Colder than an average day on Mars, for comparison.
The National Weather Service has been warning of dangerously cold temps in the forecast for this weekend. Forecasters say the arctic blast is once in a decade cold. Actual air temperatures in the Bangor and Downeast areas are expected to be near -16, Saturday morning. Northern areas of the state could see actual air temps near -25.
When factoring in wind chill, in many areas the air temp will feel like the -40s. Mt. Katahdin has a forecast wind chill of -90 degrees. For comparison, it will be only slightly warmer on the surface of Mars.
According to the National Weather Service, the average temperature on Mars is about -81 degrees F. Of course temps can vary wildly on The Red Planet. The NWS says, "temperatures range from around -220 degrees F. in the wintertime at the poles, to +70 degrees F. over the lower latitudes in the summer."

Another comparison - It will be warmer on the summit of Mt. Everest. The highest peak in the world has a forecast wind chill of "only" -47 degrees F this weekend.