Absolute Vorticity

00z GFS is cutting the low through Illinois, and we're back into the 50s by New Year's. Still have a shot at seeing an inch or two on the ground, but the fat lady has sung. That numerically slight verification advantage the Euro has over the GFS sure does feel pronounced in the winter.

mikeyp wrote: ↑Sun Dec 18, 2022 7:54 pm At least the bengals won!!! Who Dey!

Great to send Brady and crew walking the plank! Next weekend continue the momentum and beat his former team at Foxboro!

Currently 19 here in G'ville and progged for around 14 Mon morning.

16 degrees here in Somerville this morning so far

It's been a no contest between the models, as far as far as the medium range of 5-7 days out. Hopefully the GFS can improve in the shorter range we're entering. Still going to be a huge nuisance of a wintery blast for people traveling. The just south of Indy to near Chicago track path should get narrowed down quite a bit through today's modelling. I think tomorrow's 12z suite will have sampled all the shortwaves, so if any last minute changes are coming we'd probably see it then

Good Morning and I see the gfs has the low going through North Dakota lol. But a big change and even if the gfs is correct with its current track or one it had over the past 3-5 days you can't give that model a passing grade. No doubt the Euro has been throwing out a forecast that changes a little here and there but nothing major like the gfs. I agree with Bgoney that the noon models on Tuesday should have much of the info they need. Will be back on later this morning and my overall thoughts have not changed since I very seldom change with model output but will change if the players on the field are not where I believe they should be in about 24 hours. The models are a great tool to use in forecasting and my problem is I need to use them more but again the old saying you not going to train an old dog new tricks. Yes and the North Dakota is not what the model showed but just giving a shot to the gfs.

Oz Ensembles from EU

Good morning all and In my opinion, all 3 global models are in very good agreement now with this system. For the most part, this system tracks thru Central or NW IN and intensifying as it does so. For us locally, I think rain develops on Thursday as we spike up into the 40s. Once the front passes after midnight Thurs night temps crash into the teens by the time you wake up Friday morning. Temps hold steady or continue to call on Friday also with very strong winds continuing. It will still be breezy even on Christmas Eve / Day but the big time winds will be over by then. Snow wise... I think we'll see something like 1-2" behind the front. Then we get the dry slot which might be a saving grace for flash freezing prospects. It sure isn't going to hurt in that regard. It will kill our snow chances though in the wrap around on the back side. North of Cincinnati, the I-70 Crew has a shot at additional accumulations on Friday. But as modeled right now... for us down here, the snow part is basically over minus some flurries or snow showers that might reduce visibility from time to time, but I think the worst of that issue is well north and west of us locally. I think a good snowfall forecast for our coverage area is a general 1-4". Lesser amounts over us down here thanks to the dry slot and better amounts as one heads north and esp NW of our local area. Still an impactful system. The wind could cause power outages and with the cold coming in that is a very bad thing. That's probably going to be the most impressive thing for us. Wind, cold and potential power outages and not so much the snow part of it. I'm not completely sold right now on the flash freezing being a huge issue because of the dry slot and strong winds having a chance to maybe help with the water being on the roads. Flash freezes are so rare in our area, they are tough to predict and everything has to go right. If it weren't for the dry slot I'd be all in on it but that's what is holding me back. My post is hitting hard on the wind and power issues more then anything.

not looking good for an OV snowstorm anymore. looks like shes headed for the upper midwest. what a bummer, but also remember we are in a La Nina and those almost always favor the upper midwest and also the northwest with more cold and snow vs a El-Nino winter.

airwolf76 wrote: ↑Mon Dec 19, 2022 8:32 am not looking good for an OV snowstorm anymore. looks like shes headed for the upper midwest. what a bummer, but also remember we are in a La Nina and those almost always favor the upper midwest and also the northwest with more cold and snow vs a El-Nino winter.

Despite being in a blocking pattern we still fail. The PNA's position is what is screwing us over. We needed it to be right along the West coast and not off shore. That's pretty much it.

tron777 wrote: ↑Mon Dec 19, 2022 8:33 am

airwolf76 wrote: ↑Mon Dec 19, 2022 8:32 am not looking good for an OV snowstorm anymore. looks like shes headed for the upper midwest. what a bummer, but also remember we are in a La Nina and those almost always favor the upper midwest and also the northwest with more cold and snow vs a El-Nino winter.

Despite being in a blocking pattern we still fail. The PNA's position is what is screwing us over. We needed it to be right along the West coast and not off shore. That's pretty much it.

I agree . without a doubt

Good Morning and a few thoughts before we wait for the model runs. The NAM is getting in on the action as well and we know that model really loves to throw out some wild outcomes and does much better once we get within 48 hours. I will not change until Tuesday but Les mentioned the pna and yes that will affect the outcome but I am going across the country and something I saw but was not expecting. The high pressure over southeast Canada was expected to be in the 1030-35 range later this week but the most recent models have it at 1045 and further west. This makes a difference of where the low pressure can head towards with less resistance. That is just one of many items we always look at when trying to make a forecast. The attach of the polar air is another item we must take in account. I have this digging deeper and one reason was that we did not have a southeast ridge trying to keep it at bay so I believe it will form a storm over southeast Texas instead of northeast Texas. These items are just model output and over the next 24 hours I will spend even more time on pressure changes and see which model or models are handling the changes before the storm forms. Exciting times ahead and by 2pm on Tuesday I will throw out my first forecast. One last item and Bgoney and Les mentioned the dry slot which we are so aware of and can be a snow lovers worse enemy. This storm does look to bomb out and this imo delays this system from occlusion and that is why I at this point I expect a longer period of snow on Friday.

This system is just getting into the NAM's range now so we will probably see some entertaining solutions this week.

Wind Chill values are downright nasty for Friday morning, regardless of whether or not we get any snow. Can you say instant frostnip?

NAM is even West of Chicago now at it's early stages in the storm's development.

tron777 wrote: ↑Mon Dec 19, 2022 9:46 am NAM is even West of Chicago now at it's early stages in the storm's development.

It’s trying to shove the ridge West to make us happy!

fyrfyter wrote: ↑Mon Dec 19, 2022 10:02 am

tron777 wrote: ↑Mon Dec 19, 2022 9:46 am NAM is even West of Chicago now at it's early stages in the storm's development.

It’s trying to shove the ridge West to make us happy!

Same ole, same ole every year. First an East Coast low... then an Apps runner and now it's MSP to Chicago type storm. Maybe on the next run it's congrats Seattle?

12Z RGEM has a 999 MB low at the end of its run (84 hours) over NW IN. St. Louis up thru Wisc and just West of the Chicago Metro would do well with that solution.

This run of the 12Z GFS MIGHT come in a tad SE of the 6Z run. 1009 MB low over the TX Panhandle at 66 hours vs the 6Z run which had the low at 1005 MB over the Panhandle of OK. So weaker is good. Weaker would mean a further SE track. I doubt this thing gets weak to help us with big snow totals, so the best we can hope for is a slight weakening of the overall system to help us gran a couple additional inches in the wrap around snows. That's probably the legit "high ceiling" for us. Otherwise, if this thing really gets cranked up as a lot of models suggest, then the outcome should be very close to my post from earlier this morning.

Oh and a weaker system would help out in a lowering of the max wind gusts too. I want my power for Christmas so no complaints from me if we do notice a weakening trend. It's good news all around for us in my opinion should that occur.

Im not too terribly mad about the gfs run so far. Taking whatever we can get.

The low bombs over Western MI instead of North Central ILL on this run. We still mainly get missed by the wrap around. Still too West for my taste. The temp drop is so damn impressive! Temps are in the mid 40s Thurs evening and after the front passes, we're down into the single digits to maybe 10 if we are lucky by Fri morning at 7am. Wind, temp drop again is definitely going to be the headline maker for us more then anything. The snow part is a little TBD still. I like what I posted this morning, that 1-4" range for our forum area. inch or less in the SE 4" in the NW. That's pretty good from this distance I think and with the data we have available. What can make me bump the totals up? If the weakening trend is indeed real and you get the track further SE then where it is now. It's the only way it'll work. If it's an IND on West track, no bueno.

GFS finally showing more sensible QPF totals for the region. Just going by this run only, verbatim, my interpretation would be 1-2" snow possible for the region

12Z Canadian ticked SE as well. By Thurs night, you've got a 991 MB Low near Bloomington IN on 0Z, with the 12Z run having the low at 994 MB near Defiance, OH.

Come on east trend!! haha

Same old song and dance with the GFS in winter. We should all just ignore it every time. All it does is lead to disappointment….. almost every time