Absolute Vorticity

It's good models are starting to show something different now we still have time for them to flip back rather than them showing this solution Saturday

BookNerdCarp wrote: ↑Thu Jan 02, 2025 11:34 am

tron777 wrote: ↑Thu Jan 02, 2025 11:32 am

BookNerdCarp wrote: ↑Thu Jan 02, 2025 11:28 am

tron777 wrote: ↑Thu Jan 02, 2025 11:25 am

BookNerdCarp wrote: ↑Thu Jan 02, 2025 11:22 am I am assuming that these mixing issues which will no doubt hit my hood are going to be icing issues. That we do not want. Any thoughts on ice accretion at this point?

I will generically say that a quarter inch or more is on the table. If temps can remain in the 20s that would be very bad news. Precip rate also is key. If it comes down heavy, it doesn't accrete as good as if it comes down lighter.

Kind of where my mind was going with the amount of precipitation with this one. Let's hope for our sake out here that doesn't last long.

The storm duration will have everything to do with the dry slot as Cincinnati01 mentioned. If we see it, there will be a lessening or even a break in the precip early Mon morning. If it does not occur then precip (mainly snow) would continue for at least the 1st half of the day Monday on the backside and add a few inches on top of the ice. To me I think we all start as snow. When does the changeover occur and for who are the details that we need to continue working on. At this time.... I think even Cincy is in the mixing zone. I'd feel better if the Euro ticked back south lol

No matter how you add it up it will be a winter mess.....but also, quite fun LOL

No doubt Matt! This storm will impact the entire forum coverage area with some form of wintry weather and significantly at that. Even if you got above freezing and saw plain rain, the ground is still cold and where it hasn't been salted, even at 33 degrees you could still see frz rain as an example. Plus if we start off as snow, the rain would probably hit the snow and freeze on top of it forming a crust. It'll all be a glacier with the arctic air moving in behind the storm.

CINCINNATI01 wrote: ↑Thu Jan 02, 2025 11:36 am It's good models are starting to show something different now we still have time for them to flip back rather than them showing this solution Saturday

For sure. Any small change can still occur esp for the next couple of main model cycles. We will start to see the energy getting better sampled probably around this time tomorrow, or shortly thereafter.

What is it looking like for Middletown/Centerville area? Any mixing/ice/rain issues there? Estimated totals? Thanks!

Snow43130 wrote: ↑Wed Jan 01, 2025 8:24 pm My daughter is getting married that day .

Congratulations!!!

CINCINNATI01 wrote: ↑Thu Jan 02, 2025 11:04 am Cold rain knocking on our door

Knew it. Every damn time. Prepping to be on the outside looking in as usual.

Come on Snow Gods!

hopefully this thing does not go any further north i wanna see you guys get it more then myself

Good Afternoon and the models wars begin. Way early in the ballgame and sticking to my outline of what may happen but again its just a timeline of a possible outcome. Say we get 24 hours of precip which is an extended period. The first 6 hours and the last 6 hours imo will fall in the form of snow.In those two time periods I can see 2-4 inches of snow. What happens in the 12 hours between is still a work in progress. Do we get another 2 hours of snow or 6 hours of snow. Do we stay all liquid during this time which would most likely be mostly frozen for the period.

I just don't like throwing out numbers if I am not confident and that is why the first 6 hours and last 6 hours I do feel confident enough to throw out totals for those 2 periods. Does that mean we have 4 inches on the ground late Monday and that is a maybe and depends what happens during the 12 hours in between.

Still 72 hours away from the start of the storm and again by later Friday I would expect models to be in rather good shape and also we can start looking at what is really going on at the surface. Many areas to watch including the energy coming into the west coast, high pressure building out of the south central Canada, the 50/50 low in southeast Canada ,the recent high that comes in here Friday and Saturday, the GOM and even the southeast ridge though that part I believe we are okay but again things can change. Forgot that very little snow cover in the northern and central plains so the high may take a little time longer to get in here.

So yes I am excited about the system because last year was such a bust. Thanks to everyone of the forum and really is team work to get the best forecast out and sure sometimes we differ on ideals and that is fine and always a good learning lesson.

The UKMET is looking good!

EU slower with system than Oz

Further north into Missouri also

Since some have asked, I will state this as best I can. NOTE: Things can and will change. So before you read this, please keep that in mind!!!

START Time: I think snow begins falling from SW to NE across the region Sunday afternoon and evening. Obviously, this depends on your location so CVG will see snow long before CMH will, for example. At CVG, I think we'll see snow starting up around midday or into the early afternoon.

Precip types: I think we all start out as snow. I think 3-4" is likely before the changeover begins. Again, your location here is critical. Folks in our S counties will be dealing with it more then folks to the north. Right now, the mixing line appears to get into Cincinnati. I do not know how far north it will go. That will be worked out in future model runs. I think we'll go from snow, to a little bit of sleet then for folks in the mixing zone, a good 4-8 hour period of freezing rain. 0,25" or more of ice accumulation. Then late Sun night / early Mon, we go back to snow and receive 2-4" additional accumulation on the backside in the deformation zone.

Amounts: Estimated amounts of course, but if you can stay all snow, then I think 8-12" plus of total accumulation is likely. I favor I-70 Crew at this time for this scenario. For those that do mix, the longer you mix the less snow you receive, right? So for Cincy, I like 3-4" of snow, then sleet and fr rain then an additional 2-4" on the back end. So we could see 4-8" of snow with icing in between. For folks S of the Metro, 2-4" of snow then 0.25 - 0.50" of ice then 1-2" of snow on the backside.

Again, this is NOT A FORECAST! just some things I am thinking about on how I think this storm may unfold. I am throwing this out there since some of you have been asking for numbers. Remember, this will change!!!

What a beautiful run!

Would love to see the kuchera numbers after that!

mainevilleweather wrote: ↑Thu Jan 02, 2025 12:47 pm Would love to see the kuchera numbers after that!

I will post the text data here shortly from the Euro to see how much QPF is actually snow. Those snow maps count sleet as snow and sometimes frz rain too FYI.

Loving the new model runs!

tron777 wrote: ↑Thu Jan 02, 2025 12:51 pm

mainevilleweather wrote: ↑Thu Jan 02, 2025 12:47 pm Would love to see the kuchera numbers after that!

I will post the text data here shortly from the Euro to see how much QPF is actually snow. Those snow maps count sleet as snow and sometimes frz rain too FYI.

May need you to explain the numbers to me again haha. I forget what they mean. I am obviously in the Maineville area!

mainevilleweather wrote: ↑Thu Jan 02, 2025 12:53 pm

tron777 wrote: ↑Thu Jan 02, 2025 12:51 pm

mainevilleweather wrote: ↑Thu Jan 02, 2025 12:47 pm Would love to see the kuchera numbers after that!

I will post the text data here shortly from the Euro to see how much QPF is actually snow. Those snow maps count sleet as snow and sometimes frz rain too FYI.

May need you to explain the numbers to me again haha. I forget what they mean. I am obviously in the Maineville area!

See this thread: viewtopic.php?t=112

cloudy72 wrote: ↑Thu Jan 02, 2025 12:52 pm Loving the new model runs!

Hey Mike! Glad to see you. As it stands right now, you're looking very good Sir!

Looks good Les. Our typical OV multi-layered fruitcake of a winter storm only with much higher numbers

Where I live, it looks like we are going to get a lot of freezing rain between the initial snow and back end snow. Time to get the ice chopper and pain killers ready.

Here's the 12z Euro text data for CVG:
Taking the data at face value, we start as snow, but look at the last column. That number creeps above 540 so I would say some sleet occurs in there. The second column of numbers is 850 temps and it does stay below zero so at CVG, if this is correct, the frz rain would stay to our south. Then, we get more snow of course once the mid levels cool back down. So if we add up the QPF, we get a total of 1.44" and out of that, IMO about half of it would fall as sleet. So taking the Euro at face value, I'd go with 6-8" of snow at CVG and some sleet too. I'd go with 10-15" if it were all snow mind you.

Bgoney wrote: ↑Thu Jan 02, 2025 12:59 pm Looks good Les. Our typical OV multi-layered fruitcake of a winter storm only with much higher numbers

Thanks! Just a rough outline. My best guess right now for the region.

allowat3 wrote: ↑Thu Jan 02, 2025 1:01 pm Where I live, it looks like we are going to get a lot of freezing rain between the initial snow and back end snow. Time to get the ice chopper and pain killers ready.

No doubt Mark. No doubt my friend. My biggest concern is the loss of power with these cold temps for folks that get into that scenario.

Ice accretion creeping into the area- so at least .10” I’ll keep my 4-6” right now, and throw in the ice.