Daily Archives: March 22, 2018

Time posted: 7:21 pm

Thursday Evening Update

Good evening, everyone. I wanted to drop by for a quick update on the Winter Storm THREAT for parts of the region to start the upcoming weekend.

In the overall scheme of things, my thoughts haven’t changed, with the greatest threat for heavy snow across the north and northeast. That said, the model trend, sans the NAM, has been nudging this thing a little farther south.

The European Model precipitation type shows the fine line we are walking, between heavy rain an heavy snow. Notice there is only a VERY narrow band of mixed rain and snow, with a touch of sleet to start…

This is not a freezing rain setup.

Here’s the snow map from that run of the European…

The European Ensembles have a similar placement…

The GFS has a similar placement for the heaviest snows…

The afternoon run of the RGEM (short range Canadian) only goes out through midday Saturday, and is very similar to the European…

Last night, and countless times over the years, I talked about the NAM overdoing Warm Air Advection. That’s a well known bias of the model, which usually results in precipitation being too far north. After a normal looking 12z run, the 18z run blew up to the north…

Again, that looks too far north and too widespread because the model overdoes Warm Air Advection.

My earlier thoughts remain my current thoughts on the areas most at risk…

Here is a look at the Winter Storm Watch for the north…

I should have a First Call For Snowfall late tonight. Have a great evening and take care.

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Time posted: 12:49 pm

Updating The Winter Storm THREAT

Good afternoon, everyone. It’s our third Winter Storm THREAT in less than two weeks, and it’s a system poised to bring a swath of heavy snow to part of the region. The impact time is late Friday night through Saturday and Saturday night.

I’ve set the stage for this potential all week long, with a MEGA temperature gradient feeding low pressure moving in from the northwest.

Here’s the risk area I put out last night on WKYT…

My current THREAT map focuses a little farther south…

In a setup like this, you have to anticipate additional trends in the models. The morning model trend was farther south, and that’s why I’m giving myself additional wiggle room on that map.

A Winter Storm Watch has already been issued across northern Kentucky, but we will need additional counties to be added to this farther south into Kentucky and all the way into West Virginia…

I mentioned the models have shifted south, all showing the heaviest snow along and south of the Ohio River…

NAM

GFS

Canadian

A few thoughts:

  • Additional model trends are very likely, with the heavy snow swath shifting a little south or north.
  • At this point in the game, a massive shift is not very likely.
  • Heavy, wet snow will be noted within the above corridor. Several inches will be possible.
  • You will also note the SUPER sharp cutoff on the southern and northern edges of the snow swath. A few miles could make all the difference in the world between a cold rain and thumping snow.
  • Outside of the narrow swath of heavy snow, heavy rain will fall. 1″-2″ of rain may cause local high water issues. Some thunder is also possible, even with the snow.

I will have updates later today, so check back. Make it a good one and take care.

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Time posted: 2:35 am

Winter Storm THREAT For Saturday

Good Thursday, folks. March has been nothing short of incredible, with significant amounts of snow and very cold temps, and it’s not done just yet. Another system threatens to bring a swath of very heavy snow to parts of the state on Saturday, and that’s why we are back into another Winter Storm THREAT.

The weather out there today is nice, with  highs reaching the 40s in the central and east, with near 60 degrees in the west. Skies are sunny… Enjoy.

Friday will find temps in the 40s across the far north and northeast, with temps in the 60 degree range in the west. Temps may hit 50 or so in between those two.

That same temperature gradient becomes even stronger on Saturday. We may see a 40 degree temp swing across the state…

Low pressure rides that boundary and feeds on the mega gradient, producing a lot of precipitation. A swath of VERY heavy snow will be noted on the northern edge of the precip shield, and that may very well impact the northern half of the state. Here’s the Winter Storm THREAT area…

Those lines may go north or come a little farther south as we get closer, and can get a better handle on the EXACT track of the low. For now, I feel pretty good with the outlined areas.

The models are very similar to my map. The latest European Model has come south some…

NAM

The NAM usually overdoes the warm air advection early on, as it loses it, it corrects south a bit.

GFS

In addition to the snow threat in the north and northeast, we may also deal with some local high water issues developing across the rest of the state. A general 1″-2″ of rain is possible, with locally higher amounts…

GFS

Canadian

The setup for next week turns milder, but we are likely to see additional rounds of showers and storms moving in. I wouldn’t be surprised if we get into another high water threat or two.

Looking even farther down the road, another much colder than normal period looks possible to close out March and begin April. Sigh.

I will have updates later today, so check back. Have a good one and take care.

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