12/28 - 2pm - A Difficult Snow Forecast

Hope that everyone in Louisville enjoyed the dusting of snow that came last night. Here's a little 6-inch snowman I was able to put together as the snow was falling:


The New Year's snow chance is still on the maps. The computer models are having difficulties trying to hammer down a track for this storm, but I think we may have a shot at 1-4" of snow. The precipitation amounts are different on all of the models right now, so that's about the best estimate I can offer at this point.

The 12z NAM run is a little warm for us in Louisville, but the track of the low is sufficient to generate a good snow around here if temperatures cooperate. There's a coastal low that may form as well, and that could impact how much precipitation we receive and the storm track.

The 12z GFS run is similar to the NAM, but the low is further east by a few miles. This helps to lower our temperatures a little bit, so we wouldn't have as much rain before the precipitation changes to snow. That coastal low shows up on the GFS as well.

The 12z ECMWF (Euro) is difficult to read because of the large time difference between frames this many days out, but you can see that it favors the low pushing further east and pushing off the coast.

Here's what the NWS in Louisville says about this system:

SO...WHAT KIND OF PRECIPITATION WILL IT BE? THAT IS A DIFFICULT QUESTION TO ANSWER AT THIS TIME. TAKING OUR BEST SHOT...FOR WEDNESDAY THROUGH THURSDAY IT LOOKS LIKE THE NORTHERN SECTIONS OF THE AREA /SOUTHERN INDIANA AND NORTHERN KENTUCKY/ COULD SEE PRIMARILY SNOW WITH SOME RAIN MIXING IN DURING THE WARMEST AFTERNOON HOURS. CENTRAL PORTIONS LOOK TO BE A RAIN/SNOW MIX...AND SOUTHERN KENTUCKY SHOULD SEE MOSTLY RAIN WITH SOME SNOW MIXED IN WEDNESDAY NIGHT.

....

CANNOT SAY WITH CONFIDENCE YET JUST HOW MUCH SNOW WILL FALL...BUT IT DOES LOOK LIKE ACCUMULATING SNOWS WILL BE POSSIBLE LATER THIS WEEK JUST ABOUT EVERYWHERE. STAY TUNED.

From what I've seen, I think we may start with a period of light rain on Wednesday evening as the low approaches the area. Cooler temperatures should filter in and change everything to snow by late Thursday as the low moves to our east. How much snow falls on Thursday and Friday will be determined by the track of the low as it moves northward. If this storm rides up the west of the Appalachians, expect more snow than if the storm moves out to sea or if the coastal low overpowers it. I still say this will be a widespread light snow event, but there's still quite a bit of wiggle room for precipitation amounts and storm track at this point.