January 5-6th, 2025 The Double Digit Storm

[tron777]

Latest thinking from the boys:

The next chance for wintry precipitation arrives later Sunday into
Monday thanks to a low pressure system moving east out of the Lower
Mississippi River Valley. The track of the low pressure system will
have a substantial impact on the precipitation type observed across
the area. Current ensemble guidance clusters tracks along or south
of the Ohio River. If this guidance holds, snow, and perhaps some
sleet or freezing rain, would be the favored precip types across the
area. Areas north of the Ohio River would favor more snow while
areas closer to and south of the river have much more uncertainty.
The possibility of difficult travel on Monday should be monitored.

Below average temperatures will occur for the middle of the week
before much colder air surges in towards the end of next week.

[tpweather]

Good Morning Les and once again another great post. Once the storm forms then we look to the west and watch the warm front that will be part of equation. At first we see a storm that goes from the southern plains into the Ohio Valley. This part of the storm is a southwest to northeast track. Then the storm will finally stop moving northeast and head east. When and where is key to the different types of precip. I feel confident that we start out as snow and end as snow. The period in between will no doubt be a close call for us locally. This is really a longer than normal time period for a storm to move through here and we may see 24-30 hours of precip and of course varying intensity.

Like Les mentioned to get a bigger snow total you are playing with fire because that line between snow and some form of ice can be narrow. Locally we really want to see the low itself to go from say Memphis to Nashville into southern Kentucky before shifting east. A path from say Memphis to Owensboro and then gets into southern Indiana will no doubt give us a better shot of mixed precip.

Yes a nice storm and one that will have many impacts and will need to watch the trends over the next few day and Friday is probably an important day and could be the day we see any major shifts. 25-50 miles can be the difference between say 8 inches of snow and 2 inches with ice.

That is not a forecast but an example what could happen.

[airwolf76]

I was watching an overnight forecaster doing a live on youtube he was saying a 5-9" type event for Cincinatti area if it remains mostly snow

[tron777]

Good Morning Les and once again another great post. Once the storm forms then we look to the west and watch the warm front that will be part of equation. At first we see a storm that goes from the southern plains into the Ohio Valley. This part of the storm is a southwest to northeast track. Then the storm will finally stop moving northeast and head east. When and where is key to the different types of precip. I feel confident that we start out as snow and end as snow. The period in between will no doubt be a close call for us locally. This is really a longer than normal time period for a storm to move through here and we may see 24-30 hours of precip and of course varying intensity.

Like Les mentioned to get a bigger snow total you are playing with fire because that line between snow and some form of ice can be narrow. Locally we really want to see the low itself to go from say Memphis to Nashville into southern Kentucky before shifting east. A path from say Memphis to Owensboro and then gets into southern Indiana will no doubt give us a better shot of mixed precip.

Yes a nice storm and one that will have many impacts and will need to watch the trends over the next few day and Friday is probably an important day and could be the day we see any major shifts. 25-50 miles can be the difference between say 8 inches of snow and 2 inches with ice.

That is not a forecast but an example what could happen.

Tim, having the warm front set up south of I-64 is ideal to keep the deepest moisture over us as well as the colder temps. Lots of complex parts though. How quick does the system begin to shear will also impact track, duration, and precip intensity. We want to see where the best frontogensis sets up and that'll tell us where that heavy band of snow that certainly could be in excess of 6" for someone. As long as the storm doesn't weaken on the models, someone will be under a water winter watch and then a warning IMHO with this one.

[Bgoney]

As things stand atm , this would be a rare occurrence for our tri-city region of Dayton/Cbus/cvgland, with all locations receiving appreciable accumulations, (4+)I don’t know how far back one would have to go. They just don’t come around that often. Lots of model runs to go through

[tpweather]

As things stand atm , this would be a rare occurrence for our tri-city region of Dayton/Cbus/cvgland, with all locations receiving appreciable accumulations, (4+)I don’t know how far back one would have to go. They just don’t come around that often

Great Post Bgoney and you are correct the way things stand at the moment you don't see these happen that often. Imo this is a system with shots of cold air before the storm which means we start out as snow. The southeast ridge is weak or we are not seeing that big push of warm air that happens quite often. We should have a high to the northeast that keeps us with a northeast wind and if that stays true throughout the storm then we are in business. Will be watching those winds later Sunday into Monday morning and a change to an east or even southeast wind can spell warmer air above causing mixing issues. I hope by Saturday we are still singing this song and dance and like most storms surprises will happen and these are usually not something models will see until the storm is nearer.

[Bgoney]

As things stand atm , this would be a rare occurrence for our tri-city region of Dayton/Cbus/cvgland, with all locations receiving appreciable accumulations, (4+)I don’t know how far back one would have to go. They just don’t come around that often

Great Post Bgoney and you are correct the way things stand at the moment you don't see these happen that often. Imo this is a system with shots of cold air before the storm which means we start out as snow. The southeast ridge is weak or we are not seeing that big push of warm air that happens quite often. We should have a high to the northeast that keeps us with a northeast wind and if that stays true throughout the storm then we are in business. Will be watching those winds later Sunday into Monday morning and a change to an east or even southeast wind can spell warmer air above causing mixing issues. I hope by Saturday we are still singing this song and dance and like most storms surprises will happen and these are usually not something models will see until the storm is nearer.

When partial and full sampling is done will be the key time on modeling probably sometime starting Friday and fully Saturday. What will the trends be during that time . Shifts in strength, track and mid level warming still to come.

[tron777]

I also agree... it certainly looks to have a wide snow shield with it for a region wide event. I think there will be a 75 to 100 mile wide band of heavier totals. If current QPF holds, 6"+ are on the table.

[tpweather]

No doubt plenty of moisture available and would not be surprised if over and inch for total precip. How much of that is snow is still up in the air. I would expect ratios to start out around 12-1 later Sunday but drop closer to the 8-1 or 10-1 during much of the storm before moving back up to 12-1 at the tail end of the storm. Once we get closer and more detailed forecast will be needed and yes with stronger systems a wider range of snow totals will be in force. Example would be 3-6 inches but sure somebody gets under a decent band longer that total could be 8 inches or a mix happens during the storm could be 2 inches. Just way to early in the process plus even during a storm changes need to be made as the storm unfolds. Hope its an all snow even but if you live south of I-64 a frz/rain event is possible and would not be surprised to see an Ice Storm Warning which is rare in itself

[tron777]

No doubt plenty of moisture available and would not be surprised if over and inch for total precip. How much of that is snow is still up in the air. I would expect ratios to start out around 12-1 later Sunday but drop closer to the 8-1 or 10-1 during much of the storm before moving back up to 12-1 at the tail end of the storm. Once we get closer and more detailed forecast will be needed and yes with stronger systems a wider range of snow totals will be in force. Example would be 3-6 inches but sure somebody gets under a decent band longer that total could be 8 inches or a mix happens during the storm could be 2 inches. Just way to early in the process plus even during a storm changes need to be made as the storm unfolds. Hope its an all snow even but if you live south of I-64 a frz/rain event is possible and would not be surprised to see an Ice Storm Warning which is rare in itself

Great post Tim! I think ice storm potential looks greatest in Central and SKY (depending on low track for the southern end of that) into the cold Appalachian valleys where the cold air takes longer to get scoured out. Rain IMO or ice to rain for TN on south is my current thinking. Mixing concerns as far north as CVG aren't off the table yet either. More of a sleet threat versus frz rain in my opinion there. I think your bigger ice threat remains south of us at this time.

EDIT: I'm not expecting a ton of severe wx with this system as it is shearing as it heads more west to east so that should not rob us of moisture transport from the Gulf I wouldn't think. Also due to the low maintaining or slowly weakening, WAA wouldn't be as strong as it normally would be. Just talking about how things are currently being modeled. Certainly all could change in the blink of an eye if something right now isn't being analyzed properly. But I'm going with the odds and the current data. Blocking looks good for this to not be a cutter and with the slower arrival you get better wave spacing behind the little guy on Fri. So there isn't a bunch of ridging in front so it also cannot cut or get suppressed a ton either. It is a really nice set up for this forum to be quite honest. Nice overrunning situation. Some of our best snows are not with bombing out lows. Warm air is usually too much for us with those.

[tpweather]

Wonderful post Les and just sent out an email to my neighbors and friends and just told them to expect a decent storm starting Sunday into early Tuesday and expect some bad road conditions. No predictions on snow totals but just a heads up and of course will send them an update probably Friday or Saturday.

[tpweather]

Les with the AO really going negative and the NAO going negative these are good signs that the models are doing well in handling this storm. Speaking of the AO and models are seeing quite the negative spell and later in the month are we looking at the PV nearby say either in southern Canada or the northern USA. Again where it finally ends up could make a big difference on the weather starting about 10 days from today. To strong and we just get very cold and most likely dry. Saying that we usually end up with another system before the PV really moves south and that is something I am starting to look at for the weekend of the 11th. Just a pattern and not a model forecast by any means and again we are just at the start of the pattern change and no doubt changes will occur early on before the models settle in quite nicely.

[tron777]

The NAM will start to become more of use by Friday as we start to get this within the short term model ranges. For now the Ensembles are still a good way to go but the globals really aren't that far off from each other at this time now either.

[tron777]

Wow! 0Z Crazy Uncle is a forum wide 8-12"+ (10:1 ratio) It's a region wide shut down lol

[tpweather]

I agree Les and will watch the clipper for later Thursday into early Friday to see the track of that system plus start to see how strong the high pressure coming in after that system plus a high coming down from western Canada as well. Will these highs be weaker,stronger or the status quo and this also can help in figuring out the storm late in the weekend

[tpweather]

Wow! 0Z Crazy Uncle is a forum wide 8-12"+ (10:1 ratio) It's a region wide shut down lol

Okay Les who is the Crazy Uncle and I know with my family its me looking in the mirror

[tron777]

Virtually all models have this huge band of snow that could run anywhere from I-70 to I-64 in Ky depending on the model. Cincy in a good spot since we're right in the middle of the two goal posts.

[tron777]

Wow! 0Z Crazy Uncle is a forum wide 8-12"+ (10:1 ratio) It's a region wide shut down lol

Okay Les who is the Crazy Uncle and I know with my family its me looking in the mirror

UKMET

[tpweather]

Thanks Les and yes I believe overall a 10-1 ration seems correct but at times early on and late in the storm those could go up a tad higher and say 12-1 but for how long is just not known at this time

[airwolf76]

Wow! 0Z Crazy Uncle is a forum wide 8-12"+ (10:1 ratio) It's a region wide shut down lol

man thats nice. now i am starting to get just a little jealous lol

[tron777]

Wow! 0Z Crazy Uncle is a forum wide 8-12"+ (10:1 ratio) It's a region wide shut down lol

man thats nice. now i am starting to get just a little jealous lol

As Bgoney stated earlier, I cannot remember when the last time we had a region wide snowfall such as this? (Assuming it comes in as currently advertised lol) Many years! For some of you on this forum you have not seen anything above 6", 8" or 10" mark since Marc h of 2008! I had 10" in Feb of 2021 during that localized CVG Event. That was my last IMBY big one.

[tron777]

The morning run of the NWS Blend of models gives everybody around 6" of snow. CVG, DAY, CMH and everywhere in between. Man, this is awesome!

[Bgoney]

Main shortwave doesn’t come onshore in California until Friday PM

[airwolf76]

Wow! 0Z Crazy Uncle is a forum wide 8-12"+ (10:1 ratio) It's a region wide shut down lol

man thats nice. now i am starting to get just a little jealous lol

As Bgoney stated earlier, I cannot remember when the last time we had a region wide snowfall such as this? (Assuming it comes in as currently advertised lol) Many years! For some of you on this forum you have not seen anything above 6", 8" or 10" mark since Marc h of 2008! I had 10" in Feb of 2021 during that localized CVG Event. That was my last IMBY big one.

im surprised you even had that much from the Feb 21' storm. that one got us both then because i had 20" from that one. which was my last big one also.

[BookNerdCarp]

I'm thinking it's been 10+ years since we have had a 6+er in my hood. I could be wrong.