(12-10-10) Updated Snow Forecast

With the last two model runs, it now appears that the Low will indeed move farther to the north in Indiana, which will decrease our chances for large amounts of snow accumulation. As seen in the graphics below, the main bulk of accumulation will be in Northern Indiana and Michigan. The left image is from the 12z GFS Model and the right image is the 12z NAM Model from today. Purple indicates 1 inch, blue 2 inches, yellow 3 inches, light green 4 inches and so on.

While the models don't agree fully on the amount of snow in our area, what is certain is we will get something. It likely won't be much, but with winds on Sunday gusting to 30-35mph as this strong low pressure moves to the north and east of us, blowing snow which can make dangerous road conditions will come into play.

So what about timing? Right now it looks like Saturday will be an all rain event with temperatures peaking into the 40s during the afternoon hours. A strong cold front with this deeping low moves towards us during the daytime and should be moving through the area late Saturday night.

As seen in the graphic at left the 540 thickness line (the rain/snow changeover line, first blue line on these graphics) is just to our west at 7pm on Saturday. It moves well past us by 1am Sunday morning, indicating the passing of the frontal system. What this means is that any precipitation after say midnight on Sat/Sun will fall in the form of snow. And it appears that there will be an ample amount of wrap around moisture from this deepening low to provide some accumulation.

The GFS Model is also showing a dry slot moving through just after the front passes. This may mean that accumulations could be lighter during the overnight hours and we may see the bulk of the snow accumulate during the wrap around moisture on Sunday. This would lessen our totals, but some models are not showing this dry slot. We'll have to see how it pans out.

So what does this mean for us? It looks like we should see somewhere in the range of 1-3" across our area, with more to the north and less to the south of us. Based on current model data, this seems the most conservative estimate. If the low moves a little more south than expected, these totals could rise, but the models aren't indicating that at the time. Temperatures will take a significant plummit overnight on Saturday into Sunday and it appears that we will be in the upper to mid 20s by daybreak with falling temps throughout the day on Sunday. Look for a low in the mid teens on Sunday night.

I've posted an updated snow prediction map of my own below. I'll have more on this as the system gets closer.