December 2021 Weather Discussion

[airwolf76]

The deal with the MJO at this time... it looks to go into 6, then tries to get into 7, but loops back into 6 again, before finally getting into 7 again as we approach mid month. That re-looping back into 6 if correct, delays any sort of pattern change until after mid month. Not saying we won't see some snow in the first half of Dec, but the chances are looking low at this point in time. Hopefully the second half has a better outcome in time for Christmas.

Thats fine by me. I have quite a bit of outside work I wanted to get done in the next few weeks. I would not cry if winter held off till January at this point

[tron777]

So looks like the 12z NAM went further north with most of the rainfall for tomorrow. CVG only showing 0.04" with 0.27" at DAY.

I have one more big leaf grinding to do later this week so the less rain on Wed the better. 12Z GFS showing 0.24" at CVG, 0.16" for DAY and CMH.

[tron777]

The deal with the MJO at this time... it looks to go into 6, then tries to get into 7, but loops back into 6 again, before finally getting into 7 again as we approach mid month. That re-looping back into 6 if correct, delays any sort of pattern change until after mid month. Not saying we won't see some snow in the first half of Dec, but the chances are looking low at this point in time. Hopefully the second half has a better outcome in time for Christmas.

Thats fine by me. I have quite a bit of outside work I wanted to get done in the next few weeks. I would not cry if winter held off till January at this point

I always want snow and cold for the Christmas - New Year's period. Not sure what'll happen yet for the 2nd half of Dec but until the MJO gets on the move and esp move on to the better phases, little for us is going to change.

[tron777]

The one thing that I do like in the first half of December, is the snow cover should be building up nicely in this pattern for the Rockies and N Plains areas. We need that anyway for help in getting the cold further SE should the pattern allow for it to do so later in the month. There looks to be at least 3 cutters in the first couple weeks of Dec.

[airwolf76]

The deal with the MJO at this time... it looks to go into 6, then tries to get into 7, but loops back into 6 again, before finally getting into 7 again as we approach mid month. That re-looping back into 6 if correct, delays any sort of pattern change until after mid month. Not saying we won't see some snow in the first half of Dec, but the chances are looking low at this point in time. Hopefully the second half has a better outcome in time for Christmas.

Thats fine by me. I have quite a bit of outside work I wanted to get done in the next few weeks. I would not cry if winter held off till January at this point

I always want snow and cold for the Christmas - New Year's period. Not sure what'll happen yet for the 2nd half of Dec but until the MJO gets on the move and esp move on to the better phases, little for us is going to change.

I would be okay with a little bit of snow for Christmas and new years eve just hope it doesn't happen before that.

[tron777]

12Z OP GFS looked awful for the entire run for winter lovers. Plenty of cutters in there though to build up the snowpack to our NW as I mentioned earlier. The 12Z GEFS isn't too bad until 12/10 and beyond. Major +EPO / -PNA pattern just like the OP GFS. We've got some mild weather coming up. A few cold shots too but December is going to skew above normal for at least the first half of the month IMO.

[tron777]

So looks like the 12z NAM went further north with most of the rainfall for tomorrow. CVG only showing 0.04" with 0.27" at DAY.

I have one more big leaf grinding to do later this week so the less rain on Wed the better. 12Z GFS showing 0.24" at CVG, 0.16" for DAY and CMH.

12Z Euro is like the GFS with rainfall amounts on Wed.

[cloudy72]

12Z OP GFS looked awful for the entire run for winter lovers. Plenty of cutters in there though to build up the snowpack to our NW as I mentioned earlier. The 12Z GEFS isn't too bad until 12/10 and beyond. Major +EPO / -PNA pattern just like the OP GFS. We've got some mild weather coming up. A few cold shots too but December is going to skew above normal for at least the first half of the month IMO.

Great post Les and I agree. At least we will be getting more exciting weather next week than what we have been getting. Gonna be awhile for snow lovers, but I bet we cash in towards Christmas and into Jan/Feb....at least I hope we do. LOL

[tron777]

12Z Euro is trying to throw us a nibble. A wintry mix changing to rain (longer changeover for I-70 Crew) but this is like around 12/7 to 12/8 so it's way out there in the future. We can't put much stock into that at all right now.

[tpweather]

Good Afternoon and got my yard cut one last time for the season. Probably one more round with leaves but that should be a quick and painless job. I believe the Euro has decided to be the GFS with the current pattern because it changes just about every run and they are usually so far apart from the previous run. This tells me changes are coming because a model does not do a 180 turn if the data is still the same. Sure once in awhile we get a bad set of data and a really bad run but since late last week this model has no clue and imo that is a good sign. Colder air will continue to show up more and more over the next several days and yes models will be models and then boom they correct themselves. Folks we have tons of cold air to work with and does not take that much to bring it further south. Sure would love to see more snow on the ground but in early-mid December the amount of sunlight is nearing its lowest output and this can help in keeping the cold air cold even when it moves further south. If the mjo was stronger then I no doubt would have more worries but its very weak and probably not the mover of the pattern. I mentioned last week the models would be different early this week but the changes are even too much for their normal wackiness. My guess a few more days of this and hopefully the models become more in tune with the pattern that is setting up.

[tron777]

Good afternoon Tim... your optimistic tone is good to see in your posts. I want to be wrong, but we maybe in for a long wait unless we get a little something coming around 12/7-12/8. Outside of a very low chance there and I mean low, I don't see anything else cooking for snow lovers thru mid month at this time. Tellies are all in the wrong phases. Just getting a better Pacific pattern is really all that is needed. Everything else would fall into place. So far, all I see on the Pacific side is a -PNA and / or a +EPO. Those both spell bad news for us.

[cloudy72]

Good afternoon Tim... your optimistic tone is good to see in your posts. I want to be wrong, but we maybe in for a long wait unless we get a little something coming around 12/7-12/8. Outside of a very low chance there and I mean low, I don't see anything else cooking for snow lovers thru mid month at this time. Tellies are all in the wrong phases. Just getting a better Pacific pattern is really all that is needed. Everything else would fall into place. So far, all I see on the Pacific side is a -PNA and / or a +EPO. Those both spell bad news for us.

What is sad is, at least for the 12z GFS run, you typically see some wild temp swing prediction or mega fantasy storm to look at. This run didn't even have that (at least for us).

[tron777]

What I am seeing on most of the guidance is that EPO fold over ridge does occur (that I mentioned last week) and we get a brief +PNA. That coincides with the Dec 6-7th storm system which gives us a wintry mix to rain scenario or mostly rain per the OP GFS. Then the pattern goes to crap on all models after that thru mid month. +EPO / -PNA

[tron777]

Thanks to the folks at Local 12, here are the Dec avg's for CVG.

DecatCVG.jpg

[MVWxObserver]

So for travel the week of Dec 13th, currently its looking okay over all as my sis and her family will be coming up from NC for an early Christmas celebration.

Currently 43 here in G'ville and progged for around 28 Wed morning.

[Bgoney]

No changes from yesterdays thoughts for first half of Dec. Warm shot /cold shot / warm shot pattern continues similar to Nov. The two big players look to be entrenched for at least another 10-14 days. A sprawling high pressure south of the Aleutian Islands has been a mainstay for weeks , in tandem with sprawling trough over Alaska and wester Canada. Hopefully a well placed surface low timed with a cold shot can produce a few flakes, but with the NAO going neutral to + cutters should rule. Concerning the High pressure south of the Aleutians , notice how it matches up fairly well with SST warm anomaly. A player that has shown to be stubborn with consistency.

floop-gefs-2021113018.500h_anom.na.gif

ssta.daily.current.png

[tron777]

We're on the same page Bgoney. PV is pretty strong too along with a +AO. Going to be tough to break out of this pattern without something to majorly disrupt it. We'll see what the 2nd half of Dec shows, but the first half is not looking good. Just that small chance for some wintry weather Dec 6-7th, maybe the 8th. Whatever the timing happens to work out to be. It's a small chance at that.

[Bgoney]

Alaska to remain stormy , cold , then bitter cold

gfs-deterministic-namer-t2m_f-1638295200-1638576000-1639418400-10.gif.1dc55d1048b7a55f7fe12c833847b81a.gif

[tron777]

Plenty of cold air to work with. Just need a favorable pattern to allow for storms to use it.

[tron777]

Rain is moving into the area this morning. Should remain light IMO under a tenth of an inch for us S of the river. Up to 0.25" possible for those to the north. Dry Fri and Sat with our next rain chance coming in by Sunday. Then as we approach Tues and Wed of next week, our next front with more rain moves into the region.

Temp wise... 60+ still on tap Thurs and Fri with Thurs offering up strong SW winds with gusts to 30 mph possible. U40s to L50s this weekend. No real cold air for the next 7 days.

[Bgoney]

26 here this morning, so could see a few ice pellets in the beginning as the moisture moves in

[tron777]

I had 34, now up to 35 so all liquid here.

[tron777]

Still watching that one low chance for wintry weather around Dec 6-8th time period. GFS gives us a shot at a wintry mix to rain. CMC shows mainly snow (shocking I know lol) while the Euro is mostly rain. Typical for the models this far out. That's really the only low chance threat that I see for the next 2-3 weeks. Fugly I know, but that's what we've got going on. Otherwise, rain and mild temps will rule the weather picture.

[tpweather]

Good Morning Les and Bgoney. Many of the new folks on here probably have not seen some of the weather discussions on here when folks have different outcomes in longer term forecasts. When this happens the discussions are wonderful as each person sees the outcomes in different ways and over the years when this happens it is usually about a 50/50 split which outcome is correct. First glad I mowed yesterday as the rain is falling at the moment. We knew the warm up is coming and everyone agreed on that part of the forecast. The weekend imo was going to be the change to the overall pattern and though I may be a day or so late I still believe that will happen. Why do I believe that is going to happen when some of the computer models and the tellies they throw out say otherwise. I look at the weather across the world and try to see where the pattern is and factors that will change a pattern. No doubt Alaska has been cold over the past month and that includes the entire state which is not always true with these cold outbreaks up there. Major storm coming in this weekend and this should send mild air across much of the state and temps should rise to normal or even above normal by next week. This in turns sends the current cold air further east across much of western and central Canada. Then we need a way to get that cold into the lower 48. This of course is usually done with a big storm or several storms that push the jet further south. I believe in the several storm outcome starting very early next week. Again if the tellies are correct then my forecast will not be accurate and once I see that the tellies are correct I will change the forecast but at the moment nothing has changed in my thinking. We have plenty of cold air on this side of the globe and just grabbing some of that cold can produce winter weather for us locally. First full week of winter starts next Monday and I use the 4-4-4 rule in winter weather around here. Four weeks where the pattern is terrible and winter weather is unlikely,four weeks where the pattern is great and winter weather is likely and the one we start out with next week where the pattern is good enough to produce winter weather and chances are more of a 50/50 chance. Again each winter is different and sometimes going by weeks is not easy but if you split the winter chances for us locally you get that 1/3 of the season for each item I mentioned before. No doubt I will be watching the weather over the world the next several days and this should either confirm my thoughts or tear them apart.

[Bgoney]

I don't think we're that far apart Tim. The cold air is there, I just think the lows that could develop won't be strong enough to bring the colder air in for CVG land to give us anything substantial other than flurries/mix. Long ways out and like you , I won't care one bit to change my thoughts if need be.