Snow is on the Way
by Cody Matz
December 05, 2012 8:10 PM
Now that we are several days into December, its finally going to not only start feeling like winter, but look like it as well. We have had a pretty good run over the last few weeks with a few different record-breaking afternoons and way more sunshine than we typically see. But all good things must come to an end. Colder air swings into the region through the day Thursday with highs back to normal already by Friday and even below average, by as much as 15 degrees, as we head toward next week. Not to mention, we get to add the little white flakes that many dread. No not dandruff, but snow. Now because of the particular nature of the atmosphere at the moment, it is still unclear just when much of this snow may fall and how much we may get. But, that doesn’t mean we aren’t leaning a certain direction with some areas having the potential to get several inches of snow by Monday morning.
Lets backtrack a second though and take a quick look at just how lucky we have been entering December on such a warm note. Below is a look at several cities highs compared to average over the last week. The southwest (Winner) has been the warmest with the northeast the coolest (Aberdeen and Watertown) but still above average most of the last week.
Average highs are in the 30’s this time of the year and dropping into the 20’s for some, so to get highs in the 40’s, 50’s, 60’s and even 70’s is pretty impressive. Now, before you attribute that to climate change, other locations across North America and across the globe are dealing with temperatures on the other side of the spectrum. It’s been one of the coldest ends to November and starts to December in Alaskan history. In fact, the city of Fairbanks hasn’t gone above –20° since November 23rd, almost 2 straight weeks. Sweden, Norway, and much of Russia have seen record snows and temperatures some 50 degrees below average. China and Japan saw one of their largest early season snowfalls on record. This just proves that much of North America remains in a very warm pattern, but as you will see in the coming days that is really going to change.
With the cold will come the snow, which will likely be coating the ground in many areas on Friday. So the age-old question remains, how much will we get? Often times this question is one of the hardest to answer in the meteorological world, and unfortunately this time is no different.
Forecasting computer models have been what we call flip flopping. This is a term many may know when someone is going back and forth from one thing to another. It’s like trying to make a decision one something, but you end up going back and forth from say painting your walls white or painting them blue. Well, these forecasting models are having a similar issue. Every single time an updated version comes out, storms will disappear, reappear, move hundreds of miles, weaken, strengthen, you name it!! A little variation in each forecasting model is normal, but this is ridiculous. Right now, the best estimate is that snow will move in sometime on Thursday night and stick around through much of Friday. But just a day ago, these same forecasting models were showing 2 different storms, one for Thursday and one for Friday. But now they have combined them into one. So for the moment, it looks like a mostly dry day Thursday and a snowy day on Friday. The next to images show these 2 different forecasting model snow outputs. Pay close attention to the general area that they cover.
Notice that even though they are a bit different in overall snow amounts, they are now pretty consistent on who will get the snow landing the band mostly across southern South Dakota. Snow totals range from about an inch up to around 4, but will highly depend on just how heavy the snow falls. Right now it looks like widespread very light snow for several hours, however, there are a couple of indications that some areas could see a couple hours of moderate to heavy snow, which would add a couple more inches to those totals in some spots. So the potential for up to 6 inches of snow is there, but there is a much higher likelihood of 1-3 inches.