Monday-Tuesday Storm Update and Thursday-Friday Threat

There is a winter weather advisory in effect for Northern MoCo until 7 AM Tuesday for ice accumulation up to a tenth of an inch. However, the NWS map for ice accumulation doesn't show much for the entire county, and only shows accumulation in Damascus. When the heaviest precip falls, temps should be relatively above freezing, so even if there is some mixing it shouldn't accumulate on roads and sidewalks. Most accumulation should be on the grass. All I would say is that be careful if you have to do something this night/early morning that requires you to go out, but even then most everything will be fine. The rain should wipe out any accumulation if there is any accumulation. And yes, this is the same storm that brought 2-10 inches of snow in Texas. If anything happens that concerns this event, I will update it here.

But's there's another threat approaching our region, and it's on Thursday. If you have a friend that is interested in weather, then you might have already heard about this threat. As of now, it looks like it will be much more significant than the threat this Monday-Tuesday. It is looking like a cold air damming(CAD) situation, where we start as snow and end as a mix/rain. However, the way models are trending,  I wouldn't be surprised if this becomes an all snow event. I won't show totals because they will likely decrease once we get 36 or fewer hours away from the threat. Almost every model shows a front-end thump for Thursday. But I'll believe it when I see it on the radar!

GFS:

The GFS shows the storm starting as heavy snow around 5-8 AM and then shows it turning into a heavy wintry mix, then into plain, old rain. The backend precipitation shows wintry precipitation though. This eerily reminds me of Feb 20, 2019, another CAD situation. We started as snow, then had a little bit of a lull, then sleet and ice fell. We were forecasted to turn into rain, but we didn't and stayed in wintry precipitation. CAD lasts longer than what the models show, especially at this point out, and I wouldn't be surprised if we stay all wintry precipitation, especially with what the models are trending towards. The GFS is continuing the trend, as you will see shortly.

As you can see, the rain/snow line in the 18z run(latest run) is further southeast than the 12z run(first image). Do you see how the blue, purple, and pink colors are closer to us than in the first image? That is the southeast trend. If this keeps going, this could be a favorable snowstorm for us.

European:

The European model shows heavy snow before turning into a mix. It doesn't show it turning into rain. This model looks the best for snow lovers. I won't say totals, but it looks... good for us snow lovers. Ratios will likely be higher than 10:1, so we have to keep that in mind. Temps will be below freezing this entire storm, and below 30 degrees for everyone, according to the European model.

CMC:

The CMC shows the storm starting out as heavy snow, then quickly turning over into a mix, and then into rain. This model is the least optimistic about the cold air, showing the warm air quickly taking over.

National Weather Service:

The NWS is looking good for snow lovers. It has a high impact threat for the entire region, but medium confidence in Northern MoCo and the Allegheny Front. It has low confidence in the I-95 Corridor, which is understandable(Southern MoCo). It's rare that they issue a high impact threat for the entire region without upgrading to a high winter storm threat of a winter storm. There is an enhanced threat for the I-95 Corridor and a moderate threat for Northern MoCo. I assume that they will be upgraded to a high threat if trends keep continuing the way they are. They also have a low threat, low confidence winter storm threat for Wednesday-Thursday, but I assume that will only be for the later part of that forecast(see below).

The NWS shows a slight winter storm threat for the entire region.

So as of right now, if things keep going the way they are going, I would expect any non-essential in-person plans to be canceled. However, we are still far out. We are at the point where we know there will probably be something, but the significance of that has yet to be decided. If the models change for the worse, we may see very minimal amounts. High impact threat is a very encouraging sign, but we need the confidence to confirm it. I will make an update tomorrow.