When you hear of records like minus 108 Fahrenheit in the lower 48 you have to wonder

So, the idea of another ice age doesn't sound as unfeasible to me as it once did when you get North Pole Temperatures this far south. But, at least for now it doesn't STAY this temperature for any length of time.

For example, if you got these kinds of temperatures where they stayed low enough to actually snow from about September to April constantly of any year you might have the beginning of an ice age if it didn't warm up enough that year to melt all the snow by the next fall.

In California where I live the ocean keeps it warmer because at least for 10 to 20 miles inland it really keeps the temperature higher in most of California simply because you have 6000 miles of open warm water which acts like a heater all along the California coast from San Diego to the Oregon Border.

So, I'm thinking if there were going to be an ice age it would begin at the High Sierra Mountain Range and go all the way through the Rocky Mountains to the furthest eastern Mountain Range and then the ocean would tend to keep places warmer from about New York City southwards because of the ocean affecting the temperatures upwards. 

Where I live nearer to San Francisco the lowest ocean water temperature during the year at the surface would be around 59 degrees Fahrenheit which is about now here in February. So, water this warm tends to keep temperatures fairly high relative to places from the Sierra Nevada mountains east during the winter months in California. So, temperatures even in the winter are usually between 45 and 60 as a daytime high and seldom does the thermostat go below 40 though I think this year it hit 35 Fahrenheit at least once here on the coast so far.