Absolute Vorticity

This Week in Weather from DT that he posted last night:





The data is showing that the pattern is supposed to change from around Christmas and beyond. Early January looks really good! Hopefully the data is correct. We shall soon see!

06z NAM and GFS

00z NAM and GFS for comparison purposes

Can’t even call it a two wave event anymore, “wave” one waved bye-bye. It’s all about where is the front when the weak secondary low passes close enough to enhance the precip for parts of our area

Bgoney wrote: ↑Thu Dec 07, 2023 5:46 am Can’t even call it a two wave event anymore, “wave” one waved bye-bye. It’s all about where is the front when the weak secondary low passes close enough to enhance the precip for parts of our area

Pretty much where we stand now. There will be a band of 1-2” locally 3” but the location is a bit uncertain. Much like we are used to with snow events

Outside of that band lesser amounts.

0.5”-1.5” is probably a good call for now to cover the uncertainty. That is for Cincinnati. Lesser amounts west.

Good Morning and have not looked at the model in at least 18 hours and maybe we are getting closer to the correct outcome. How much rain is still an issue as the models are showing a rather sharp cutoff. Severe weather will be more in the wind department and even that will not be easy to reach that level. Snow and Les I agree with you that we maybe see a few flakes or a quick shot of snow as the system pulls away but again nothing to worry about with this system.

Again I believe on this forum we never thought much about the snow chances but more in the heavy rain and maybe severe side. So yes some gusty winds and hopefully a decent amount of rain but again we have that sharp cutoff as the storm is progressive.

I like Bgoney's maps for the next two weeks and more of what we have seen is a northwest flow but modified since the coldest air is on the other side of the globe plus not much in the way of snow cover to our northwest and this as well will hinder any strong cold spell.

The NAO is going positive and the AO is heading towards positive and this is another reason the upcoming system will be progressive compared to earlier this week when models thought those two would remain negative.

We are still only at Dec 7th so two weeks would put us at Dec 21st and that is when I thought we would see some changes. Can that be pushed back and again only time will tell and the MJO looks to go from the current warm phases into the COD though getting closer to the cold phases. This also is a clue that over the next two weeks expect slightly above normal temps overall and precip chances slightly below normal.

snowing

December 7th, 1941. A day that will live in infamy.
Let us never forget the sacrifices of so many men and women
For our freedom. God Bless the USA

Mjr wrote: ↑Thu Dec 07, 2023 9:56 am December 7th, 1941. A day that will live in infamy.
Let us never forget the sacrifices of so many men and women
For our freedom. God Bless the USA

Amen! Wonderful post!

airwolf76 wrote: ↑Thu Dec 07, 2023 9:43 amsnowing

Nice Charles! Sunny today in the OV.

Mjr wrote: ↑Thu Dec 07, 2023 9:56 am December 7th, 1941. A day that will live in infamy.
Let us never forget the sacrifices of so many men and women
For our freedom. God Bless the USA

Amen

So glad the sun is out today and mid 50's later, 45 now!
I figure that if we can't get into a pattern, then we might as well have mild sunny days!

Nice posts guys regarding the weekend system. 1.29" of rain at CVG per the 12Z GFS. Looking like a wet Sat afternoon and night period with the action done before sunrise on Sunday. Heaviest amounts definitely are going to be SE of Cincy with a very sharp cut off NW of Cincy as Trev was mentioning earlier.

Regarding the extended period... Tim's post looks spot on and I don't really have a lot to add right now. We should see more of the same for the next 2 weeks with changes HOPEFULLY still coming just in time for Christmas. I had the 18-20th earlier but that is going to be too soon. 23-25th seems more like it based on the latest Ensemble / Euro Weekly guidance. This also coincides with the MJO getting into the colder phases by then albeit at a weak amplitude. (Which is fine). Out to Day 16, the EPO still looks to be positive so no arctic air, but the PNA looks to go positive as we approach my targeted time period so that should help with getting more troughiness in the East. Again, all we need is air cold enough for snow. You don't want it too cold or you run the risk of being cold and dry.

12z NAM and GFS

0.5-1.5” call looks solid for now. There will be a sharp cutoff but that range will account for uncertainty.

Great Post everyone. What I do watch is the PV and as we know it is on the other side of the planet and got very strong very quickly. Saying that what I am not seeing is an extended period where the cold is getting colder in Siberia. When that happens the PV is locked in and that can lead to a long period of mild weather. I see temps from the models keeping the temps the same or even starting to rise and that is good and usually means the PV is starting to get weaker and/or moving somewhere else. I will watch this over the next week or so to see if there is any changes.Still keeping the change around the 21st which starts the last 10 days of the month. Will it be exactly and nobody knows but would believe by then changes are happening on this side of the world. Again there are other areas I want to see change and that is an increase in snowfall over the northern plains and south central Canada and at the moment nothing showing that will happen soon.

12z Euro

Good Afternoon and a really nice early December day. First of all I needed a nap during DT's video but that was long but informative. The weekend storm has come together finally I believe and yes we get a good dose of rain locally and some decent winds and yes maybe a brief period of wet snow that lasts one hour but no problems at all. I am going locally .5-1.0 as I believe the system is just a little to progressive and may not ramp up until its well east of us but again this could be a trend we see all winter even when we have more cold to deal with. Starting the 11th through the 20th I expect nothing in terms of really cold or really warm weather until we could see a bigger storm change the pattern. Does not mean we won't get and rain or snow but bigger systems look to be few and far between. I still have the 21st as my change in the pattern and again models may start to or already have started throwing that date a little further out again by next week hopefully they have come to some agreement time wise. Tell you the truth if you give me the next 13 days with near to slightly above normal temps and some minor precip in exchange for a switch to a more winter like pattern by Christmas that last for several weeks I will take that deal every time

The 18z NAM doing what the NAM does. I would say this is HIGHLY unlikely.

Here’s my 10cents worth (inflation) . Along and N/W of 71 .50”-1.00” , with points S/W of 71 .75”-1.25”

A beautiful day today for early December! 56 today IMBY while CVG topped out at 55. Another beauty tomorrow then we turn wetter on Saturday with falling temps Sat night into Sunday. The rain still looks to shut off late Sat night or early Sun morning. Bgoney's above post with his rainfall amounts look good for the OV.

Moving along... quiet for a good chunk of next week with seasonal temps. Highs in the 40s and lows in the 20s for the most part, can be expected.

CVG reached 55, DAY 54 and CMH 51 today.

I went with 1-1.5” for Cincinnati on my update yesterday, lesser amounts WNW. Most data supports 1”+.

ILN matches my thinking almost perfectly. Still some time for the contours to wiggle a little bit but overall I like the forecast.

Good Friday morning to you all! 47 currently at CVG, 48 here so a much warmer start then previous morning. Depending on how much sun we see before clouds take over, 60 is possible today for the high. Low 60s tomorrow with rain moving in esp in the afternoon and evening. It will be breezy as well. A wet Sat night ending before you wake up Sunday. Sunday will be windy with falling temps into the 30s. For rainfall amounts, I like a range of 0.50 to 1.5" depending on where you live. Heaviest SE, lighter to the NW. I won't rule out a t-storm but severe wx should not occur with this system. In terms of any backside snow, I'm not seeing it for us. That should be confined to the Apps on up into Interior New England.

Next week is mainly quiet but we should turn stormy again after that. We will continue to monitor the period from around Christmas thru New Year's with regards to the potential for the pattern to change. Until then, it's not going to happen any earlier that is for sure. Concerning the MJO, the Aussies and the CFS have the MJO wave more amp'ed with the Euro being the weakest. In terms of speed getting it into the colder phases, the Aussies are the quickest, Euro the slowest. GEFS is taking the middle of the road approach and has it going into Phase 8 around the 19th of Dec. This was as of yesterday's data. As usual, we shall see! Currently, we are in Phase 4 almost ready to get into Phase 5 as of Dec. 6th. We are probably in Phase 5 by now I would suspect.