Absolute Vorticity

Been a drizzly and misty type of day here so far. No flakes have been seen yet in my hood. Pavement is damp with a temp of 33 degrees.

925 and 700 MB temps look good for snow and wintry weather in general but the warm nose is currently at 850 MB or about 5000 feet up. The 0 degree Celc line for 850 temps is running right over Cincinnati in a SW to NE fashion. Thus, with the light precip rates what we are seeing right now it is drizzle. Temps are right at 32 degrees as well so we need to be a little bit colder at the surface too.

I see models really don't care for my ideal on Thursday but again will watch the trends in the models the next few days. I just believe that it will be the strongest of the waves and later on Tuesday into early Wednesday will watch to see where the precip is breaking out compared to what models are showing today. All we need is maybe a 50-100 mile shift northwest and it changes the forecast they are showing. Concerning tonight the best case is an all snow in terms of roads and if you happen to be that area where the snow/mix line is and stay all snow somebody could get 1 or 2 inches but that area is very narrow imo.

Would not be surprised to see a winter storm warning in western Kentucky later tonight. Precip rates of course have gone up there and with a mix of snow/sleet and frz/rain I believe less precip is needed to issue a warning compared to all snow.

Concerning the system for mid-week and starting to compare precip possible totals and its a rather large spread. One is Oklahoma City is expecting about 1/3 of an inch of total precip over the next few days compared to Dallas is expecting 1 1/3 inches of precip. That is a rather large spread and shows me that cold dry air will be battling the warm moist air. Again the distance between those two cities is similar to say Covington and Jellico,Tn.

tpweather wrote: ↑Mon Jan 30, 2023 1:36 pm I see models really don't care for my ideal on Thursday but again will watch the trends in the models the next few days. I just believe that it will be the strongest of the waves and later on Tuesday into early Wednesday will watch to see where the precip is breaking out compared to what models are showing today. All we need is maybe a 50-100 mile shift northwest and it changes the forecast they are showing. Concerning tonight the best case is an all snow in terms of roads and if you happen to be that area where the snow/mix line is and stay all snow somebody could get 1 or 2 inches but that area is very narrow imo.

Tim, totally agree on the snow band. It is going to be a couple of rows of counties wide and that's it. You can see how narrow it is on radar already over OK, AR, and MO. I don't see more then an inch or so falling either but with temps in the 20s overnight when this moves thru into early tomorrow morning, there certainly could be a few issues. Road temps right now are too warm but they have cooled thanks to the cooler temps we are seeing today. Still seeing a light drizzle falling here with 32 degrees so no changes IMBY at this time.

Must be going to do something. CB's site is out again.

In case anyone is interested.

Les I have 33 at the moment. Looking at temps to the west and northwest and they have been about what the models have shown today. So no big push of cold air but also no milder temps as well. I agree Les tonight its more about precip type than total precip for us locally. Again once precip begins you may lose a degree or two. Advisory and sure the local NWS is looking at precip types in trying to decide whether or not to throw out a possible advisory.

BookNerdCarp wrote: ↑Mon Jan 30, 2023 1:58 pm In case anyone is interested.

Thanks Matt... I saw where his site went down again too.

tpweather wrote: ↑Mon Jan 30, 2023 1:58 pm Les I have 33 at the moment. Looking at temps to the west and northwest and they have been about what the models have shown today. So no big push of cold air but also no milder temps as well. I agree Les tonight its more about precip type than total precip for us locally. Again once precip begins you may lose a degree or two. Advisory and sure the local NWS is looking at precip types in trying to decide whether or not to throw out a possible advisory.

I think they need one for at least our southern / SE counties. It is a toss up for Boone, Kenton, and Campbell. We'll see what they decide to do here soon. I looked at the rest of the Euro and how about 60 degrees and some t-storms next Tuesday? This winter sure has been a lot of back and forth which you'd expect in a La Nina anyway but some of these temp rises and drops we have seen are ridiculous.

31 as of 2pm at CVG.

The colder air is easing south and east today. Southeast Kentucky still with SW winds and temp 53 in Corbin. Lexington is at 40 and yes colder air slowly moving in there.

Checking a few reports under that snow band and Springfield, MO in the SW part of the state is at 18 degrees with 1/2 mile vis reporting moderate snow. Over NW AR in the Ozarks, you have 19-20 degrees with light snow reported. I did see one location reporting 20 and sleet falling. North Central AR is in the mid to upper 20s reporting mixed precip. In NE OK, you have Tulsa reporting frz rain and 20 degrees with McAlester in SE OK reporting moderate snow and 23. So what we are seeing here are the precip rates and dynamic cooling processes at work. Lighter precip rates means the warm nose wins and you're seeing sleet and frz rain occurring despite the cold surface temps. In areas where the precip rates are heavier, you get light to mod snow falling. We shall see how this translates NE ward as the hours tick by.

MD just issued for mixed precip in the above areas I was just talking about.

https://www.spc.noaa.gov/products/md/md0114.html

Looking outside my weather office and you can see where the raindrops are trying to turn into ice on the branches. This will probably continue as no warming expected. Roads are wet and no problems but my guess later tonight some of the sidewalks could get a little dicey so be careful because its these small systems that sometimes causes more problems because folks believe its just wet pavements and all of a sudden down you go.

tron777 wrote: ↑Mon Jan 30, 2023 2:26 pm MD just issued for mixed precip in the above areas I was just talking about.

https://www.spc.noaa.gov/products/md/md0114.html

Les its a very fluent situation and my guess several NWS offices will be quite busy trying to pinpoint advisories and maybe some additional warnings. Still believe folks in western Kentucky have a good shot at a warning and we will see in a few hours if that holds true.

A couple of nice snow showers have whitened the roofs and mulch.

tpweather wrote: ↑Mon Jan 30, 2023 2:28 pm

tron777 wrote: ↑Mon Jan 30, 2023 2:26 pm MD just issued for mixed precip in the above areas I was just talking about.

https://www.spc.noaa.gov/products/md/md0114.html

Les its a very fluent situation and my guess several NWS offices will be quite busy trying to pinpoint advisories and maybe some additional warnings. Still believe folks in western Kentucky have a good shot at a warning and we will see in a few hours if that holds true.

I agree Tim.... this is changing hour by hour without a doubt. Even some thunder and a couple of lightning strikes reported down there as well. SPC has a general t-storm outlook in that area. Very interesting!

snowbo wrote: ↑Mon Jan 30, 2023 2:31 pm A couple of nice snow showers have whitened the roofs and mulch.

Nice Bo! You may see another snow shower or two before this first wave moves away since your area is almost on the back edge of it now. Per radar, JP Land over in Columbus maybe the next location to see a few snow showers from the first wave.

Light to moderate snow shower at the moment. Pavements are wet. Snow accumulating on all others. Especially cars that have not been run. Temp of 32.

tron777 wrote: ↑Mon Jan 30, 2023 2:50 pm

snowbo wrote: ↑Mon Jan 30, 2023 2:31 pm A couple of nice snow showers have whitened the roofs and mulch.

Nice Bo! You may see another snow shower or two before this first wave moves away since your area is almost on the back edge of it now. Per radar, JP Land over in Columbus maybe the next location to see a few snow showers from the first wave.

We were posting about the same time. I can confirm this.

The 18Z HRRR has a stripe of snow running along the river on the IN side thru LOU over to LEX of 2-3" of snow for tonight's wave. Def showing ice storm / winter storm warning criteria in Western KY for frz rain accumulations of 1/4" to a third of an inch on the TN side. A tenth of an inch of frz rain by the time you get along and S of I-64 in Lexington. It's got a trace of ice accum for us and a snow amounts of less then an inch.

Winter weather advisories for parts of the local area and just south and east of the 3 northern counties in Kentucky

15Z RAP has that snow band I mentioned above much further north over SE IN and NKY counties as well as LOU and Matt's hood also. It has a trace of ice accum for our hoods and any frz rain concerns are well south of AV Country tonight per this model. Still nasty for frz rain over Western KY / TN.