Daily Archives: December 3, 2017

Time posted: 7:30 pm

Sunday Evening Update

Good evening, gang. Our big weather change is ready to blow into the bluegrass state over the next few days. This change will lead us into a nice winter setup that begins this week and kicks into high gear over the next few weeks.

I’m not going to totally rehash everything, but I want to touch on a few things flying under the weather radar. Our cold front arrives Monday night into Tuesday with showers and thunderstorms. Winds are going to be a big time player along and ahead of this front. Look at the wind gust forecast during this time…

Wind gusts of 40mph will be common for many areas into the first half of Tuesday.

The cold air continues to try and catch the back edge of the rain shield across eastern Kentucky Tuesday night and very early Wednesday morning.

The NAM looks more realistic with this run…

The GFS is also showing a few flakes flying in the southeast Tuesday night…

Northwesterly winds bring colder air in here Wednesday and Thursday, with the upper levels sending a lot of energy southward into our region from late Thursday through Saturday…

That brings our light accumulating snow potential with it, but the details are far from being known. All I can continue to say is, we have the chance to putt a little snow on the ground Friday and Saturday. Arctic air comes in behind that setup. Gusty winds will send out wind chill levels way down there.

Following that up will be another big dip shot of arctic air. This should also bring snow chances back to the region…

GFS

European

The cold shots are lined up to invade the eastern half of the country over the next few weeks. The Ensembles have not budged in showing this…

With the cold will come several chances for snow. The GFS Ensembles like the odds over the next few weeks…

The above is the average of 21 different GFS Ensembles members, so that’s pretty impressive. The Euro Ensembles have 51 members, and also has an impressive look…

Once again, I want to reiterate the fact I’m talking about snow chances over the next few weeks. I cannot get any more specific than that. Each system will be handled on a case by case basis. Are you tired of hearing that, yet? 🙂

I will have another update later tonight. Enjoy the evening and take care.

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Time posted: 1:45 pm

Tracking The Winter Changes Ahead

Good afternoon, gang. The midday update is running a little behind normal, but the weather was just too darn nice outside not to enjoy some of it. 🙂 I hope you get the chance to get outside because things are changing this week. It’s been a well advertised pattern change and we are now just a few days away from it happening.

I don’t have any real changes on the first system working across the state Monday night into Tuesday. Showers and thunderstorms and gusty winds will be along and ahead of this boundary.

Several days ago, the models were developing a wave of low pressure along this front as it slides into eastern Kentucky. The NAM is back to showing that happening, allowing for a period of light snow Tuesday night…

Some of the Short Range Ensemble Forecast members are also showing this…

Right now, I don’t see much support for what the NAM is showing. I will still go with the potential for a few flakes across far eastern Kentucky as the precipitation shield moves away.

Cold northwesterly winds take control for Wednesday into Thursday. Some light snow and flurries can fly by the time Thursday rolls around.

From there, it’s all about a potent upper level system diving in here from the northwest Friday and Saturday. The GFS continues to show this very well at 500mb…

The 6z run…

12z run…

That upper level setup would bring a heck of a clipper across our region, wrapping up as it moves through here..

6z GFS

12z GFS

I’ve said it many times in the past week, but the GFS has been pretty darn consistent with this system and the overall pattern. As shown on the above, it would be a snowmaker across much of the Ohio and Tennessee Valleys.

Gusty winds combine with arctic air coming in behind that to produce wind chills that threaten to go below zero.

Saturday morning

Saturday Night

Additional clippers and arctic shots dive in here as we head into the following week, but I’m really trying to focus on everything going on for the week ahead. It’s a busy one and gives us a lot to track. 🙂

I mentioned earlier how the European Model has been inconsistent with the upcoming week. The issues arise from a well known bias of the model in holding too much energy back in the southwestern US. It’s doing just that with the initial trough ejecting from the southwest over the next few days.

Here’s the European Model forecast at 500mb for this Wednesday…

Notice the closed upper low off the California coast. That forces the ridge overtop it to become more rounded, thus pushing the trough ahead of it too far east and keeping it a little more progressive.

Compare all that to the GFS forecast at the same exact time…

The differences are subtle, yet substantial for going forward. Look at how much weaker and farther east the system is in the southwestern part of the country. Then look at the ridge axis along the west coast and notice how it Is much sharper and less rounded than the European ridge. That sharp ridge allows energy to dig more as it dives through the base of the trough to the east.

Both solutions give us the potential for accumulating light snows later this week into the weekend, but the GFS allows for a deeper scenario.

Once the European sheds that bias, you will likely see changes in how it handles the rest of the week.

Folks, this is why I don’t just regurgitate what models say. I try to look inside each model to see why they say what they say. Sometimes they tell me, sometimes they don’t. I’m glad the Euro is a talker. 🙂

I will have another update later this evening. Have a good one and take care.

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Time posted: 1:58 am

Winter Arrives In The Week Ahead

Good Sunday to one and all. Our nice weather pattern continues out there today, but Old Man Winter is about ready to arrive. Once he takes control of the pattern, he’s likely to flex some muscle for much of the country in the coming weeks.

Let’s start with today and roll forward. Highs today will be around 60, give or take a few degrees, with a mostly sunny sky.

Southwesterly winds will kick up on Monday, boosting temps well into the 60s for most of the region. Clouds will quickly roll in with showers and storms developing in the west Monday night and rolling eastward into Tuesday. This is ahead of our cold front, ushering in the change to winter…

There is still the chance for the cold to catch the back edge of the departing rain shield across eastern Kentucky. That could cause a few flakes to fly Tuesday night…

Cold northwesterly winds settle into town on Wednesday, pushing temps to well below normal. From there, we turn our attention to a couple of systems diving in from the northwest Thursday through Saturday. For the past week, the GFS  has been consistent in showing a healthy clipper dropping in during this time frame. It varies from run to run on intensity and track, but it’s always there.

The latest run goes coo coo for cocoa puffs with the setup. If you ever want to get a clipper to bomb out, this is the upper level way to do it…

Here’s the end result…

It’s been a long time since I’ve seen a system do that around here, but it has happened before. Is it taking the setup to the extreme? Yes. Is it likely to happen exactly that way? The odds are against it, but I can’t say it’s impossible by any means.

The European Model continues to waffle on how much energy to hold back from the first system coming in here on Tuesday. That winds up playing a huge part in the late week setup. As is, the European Model aloft isn’t too far away from the GFS…

It continues to be disjointed in trying to handle all the disturbances dropping in from the northwest. Once we get past the first trough passing through the west on Monday, I bet we see big changes in the European later this week.

As is, the model brings light accumulating snows to the Ohio and Tennessee River Valleys from late Thursday through early Saturday…

How will all of this turn out later in the week? I cannot tell you that, yet, What I can say is we have an increasing chance to put some snow on the ground later this week into the start of the weekend. That would be followed by arctic air for the weekend. Honestly, I can’t say anything beyond that. Let’s see how the system shows up here in a couple of days.

But, as I said earlier, the intensity of these clippers can sneak up on the models.

The GFS Ensembles continue to be “not shy” with the snow chances over the next 2 weeks…

I will update things later today. Enjoy your mild Sunday and take care.

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