Beau Dodson's WeatherTalk Blog

 

** For planning purposes, if you have travel plans this weekend into early next week, then you will want to monitor updated forecasts.  Significant travel impacts are possible in some of my counties.  **

This event will be harsh on livestock and outdoor pets, as well.  Especially if we have wind and snow (moisture).

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Wind chills will be an issue this weekend into early next week.  At times, wind chill values could dip below -10 degrees.

Remember, wind chill is what it feels like to the human body.

Wind chill can lead to frostbite.  Bundle up.

Let me show you the wind chill values

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The National Weather Service has issued winter storm watches in blue.  They could expand this northward.  For now, they held off because we are not sure where the dry air will eat away at snow totals.

Monitor updated forecasts if you are not in the watch.

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I know everyone is watching people post model graphics online.  Hard not to see them.

Remember, all models are wrong. Some are just more wrong than others.

Try to not focus on every model run.  Try not to focus on one model run.  They will all vary in how they depict this winter storm.

Confidence in snow Friday night through Sunday is now 60% to 80%.  Those numbers have increased from the previous update.

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What we don’t know are the exact totals for every county and city.

Keep in mind that my northern counties may receive less snow.  This is highly dependent on the storm track.  Any shift north or south will change your local county forecast.

We aren’t confident about where to draw the cutoff between quite a bit of snow and not much snow.  The sharp gradient in snow totals.  Accumulation will likely be less north and more south.

A shift of 25 miles will make a big difference in snow totals.

This system is still out over the Pacific Ocean. We are threading a needle with our snow forecasts.

The bulk of the snow will fall late Friday night.  More likely, it will arrive Saturday morning and linger into Sunday.  There could be a brief lull on Saturday before more snow arrives.  Keep that in mind, as well.

What falls will accumulate. It will be cold.

Snow ratios will be high with this event. The bitterly cold air will mean snow ratios of 15:1 or greater.

There are some questions about the wind speed several thousand feet above us.  If it is too strong, then it will rip the snowflakes apart.  That would lower the ratios just a tad.

What are snow ratios?

Typically, 0.10″ of precipitation (melted) equals one inch of snow.

With this system, 0.10″ of melted liquid precipitation could be 1.5 to 2.5″ of snow. It does not take much precipitation to create a decent snow event.

There will also likely be a sharp cutoff in snow totals from north to south.  As mentioned above.

Radar may show snow falling, but it could be virga. Virga is precipitation that falls from the clouds but does not reach the ground. It is evaporating.

This is normal with bitterly cold temperatures. It is rarely too cold for snow, but it can impact how the storm acts.

High Confidence (5/5) that very cold air will be in place across the region Friday night into next Tuesday.

That means Friday night, Saturday night, and Sunday night will likely be in the single digits to lower teens. Even colder if we have snow on the ground.

Medium Confidence (3/5) in precise storm track and precipitation amounts.

Yesterday, that number was (2/5).  It has gone up a bit.

It appears that the risk of sleet and freezing rain will remain to our south. I will be monitoring this.

Some of the overnight data brought the sleet zone into the Bootheel and along the Kentucky/Tennessee border southward.

I mentioned that as a possibility yesterday.

We are now within three to four days of the event.

There is high confidence that a winter storm will impact portions of the Ohio or Tennessee Valley. The question is where and how much?

The majority of guidance indicates that snow will affect our region from late Friday night through Sunday.

If you have travel plans, then you may need to adjust them.

Again, let’s not forget that this is a bitterly cold air-mass.

Single digits are possible this coming weekend. Brrr.

If we end up with snow on the ground, then Saturday night and Sunday night will be even colder.

That means temperatures below zero into the single digits. Wind chill values of -15 to 5 above. Double brrr.

Let’s look at some raw model data.

Here is the EC AI model.  It usually scores the highest in accuracy.

These numbers are with 10:1 snow ratios.  We expect ratios to be even higher.  Thus, these numbers are actually a little low.

Keep in mind, ANY shift in the storm track will change these probabilities.

These are some pretty big numbers.  I will be monitoring trends.

What is the chance of three or more inches of snow?

What is the chance of six or more inches of snow?

Radars and Lightning Data

Interactive-city-view radars. Clickable watches and warnings.
https://wtalk.co/B3XHASFZ

Old legacy radar site (some of you like it better)
https://weatherobservatory.com/weather-radar.htm

If the radar is not updating then try another one. If a radar does not appear to be refreshing then hit Ctrl F5. You may also try restarting your browser.

Backup radar site in case the above one is not working.
https://weathertalk.com/morani

Regional Radar
https://imagery.weathertalk.com/prx/RadarLoop.mp4

** NEW ** Zoom radar with chaser tracking abilities!
ZoomRadar

If the radar is not working, then email me: Email me at beaudodson@usawx.com

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