Although Stella's near springtime arrival came as a surprise to many, AccuWeather meteorologists had their eyes on the nor'easter for quite a while.

"Almost a month ago, we noticed that the pattern that brought us the unseasonably warm weather was about to flip. In this situation, you're always on the lookout for a storm," AccuWeather senior meteorologist Dan Kottlowski said. "We've not really had any big snowstorms this year, so for some people this will be the biggest one of the season thus far."A split flow, one part situated around Missouri and Southern Illinois, and the other near southern Texas and the Gulf of Mexico, will merge together again to form the storm."This pattern recognition often spawns a nor'easter. The computer models have been focusing on the storm to come together off the coast of Delaware for days now," Kottlowski said.Meteorologists base their predictions upon previously observed patterns alongside computer models. The models allow the meteorologists to input data on a developing system in order to see how a storm will pan out."One computer run after another, it is very similar to what we've seen in the past," Kottlowski said about Stella's models. "This is one doozy of a storm."Kottlowski said nor'easters themselves are not exactly a phenomenon, as they happen quite frequently - only much further off the coast.As for safety precautions, Kottlowski recommends staying inside and hunkering down for the duration of the storm."The wind alone will create blizzard-like conditions," he said. "You don't want to compete with Mother Nature in this kind of situation."