November 2022 Weather Discussion

[tpweather]

GFS and CMC bring a front in on Thanksgiving with the northern jet and not much occurs. The southern piece comes out later and drenches the area on Sunday. I like the Euro's solution bringing in a slow moving upper low with rain late Thanksgiving into Black Friday then changing to mixed precip / snow lingering into Sat. That has been the call for about 8 days now so I am sticking with it.

I agree 100p/c Les. The key player and I mentioned sometime over the past several days is the ridging in the western states. The gfs and cmc have the ridge but is flatter and the trough is not as deep in the eastern half of the USA. The Euro has that ridge much more north to south and heads well into western Canada and this helps develop a much deeper trough in the eastern half of the USA and we get the two pieces of energy to join and further west.

PNA looks to be neutral I'd say before going negative to end Nov and begin Dec (this is per the PNA forecast on CPC's website) So we cannot yet rule out both solutions and I'm also banking on the -NAO more then anything to slow the pattern down for this system again. Again, after this system it rises towards neutral as well.

Les it looks like the pna will be neutral late in the week while the AO heads to neutral and the NAO slightly negative which should help in keeping the developing trough further west. So not a perfect set up but that usually only happens a couple times a season. So at this point I am going 70/30 in favor of the Euro. Will be fun to see the models later today as we getting within 72 hours and they should get closer in their forecasts. So I can see either model being correct or is this the old they meet somewhere in between.

[airwolf76]

So telliconnections not looking great going into December. maybe our early winter thoughts my have to be delayed a bit

[tron777]

So telliconnections not looking great going into December. maybe our early winter thoughts my have to be delayed a bit

It's already been an early start for our local area by getting frosts and freezes and a T of snow early in October. Nov has been warm, then cold and 1.6" of snow so we are ahead by 1" at this time. So to me , hat qualifies as an early start already. Pattern is going to reload by by mid Dec IMO if not before then.

[tron777]

[tron777]

MJO looks to potentially be coming out of the circle now into Weak 5 or Weak 6. As of 11/19 it was still located in the neutral circle, but on the cusp of coming out into one of those phases. Majority of the models get it going from 5, to 6 then eventually into 7 in early December where it either stalls or goes into the neutral circle. Aussie MJO model gets into Phase 8 before going into the neutral circle. We want 8 obviously to get very cold along with some storminess in December with this La Nina. I don't mind a warmer early half of Dec if we can get some action going after mid month for Christmas. I'm game!

[tpweather]

So telliconnections not looking great going into December. maybe our early winter thoughts my have to be delayed a bit

Locally in the Ohio Valley we got that early start the past 10 days or so. My guess Buffalo and many cities east of the lakes are saying that got an early start to winter as well. Concerning December and I have been talking about a milder period the first 2 weeks of the month and see no changes as the PV gets reloaded which we need that to get some really cold air around the poles. There are signs the PV may split sometime in early December but as we know from the past it takes a slower process to get that done and then where do the 2 or 3 pieces of the PV head towards. So by the 3rd week of December I expect start seeing a more winter like pattern across the USA. Exactly how it pans out is still way to early because sometimes the cold air heads to the western USA and then sometime towards eastern Canada. So leading up to mid-December does not mean we can't get some winter weather but the chances are slimmer with how the pattern is shaping up.

[tpweather]

MJO looks to potentially be coming out of the circle now into Weak 5 or Weak 6. As of 11/19 it was still located in the neutral circle, but on the cusp of coming out into one of those phases. Majority of the models get it going from 5, to 6 then eventually into 7 in early December where it either stalls or goes into the neutral circle. Aussie MJO model gets into Phase 8 before going into the neutral circle. We want 8 obviously to get very cold along with some storminess in December with this La Nina. I don't mind a warmer early half of Dec if we can get some action going after mid month for Christmas. I'm game!

I agree Les about the mjo. I have no changes in the long term. Nice to see Brian in his video talk about the late week system. He really is going with what we believe is going to happen and that is agreeing with the Euro model. Rain changing to snow showers late Friday and he makes a great point about how the upper systems this time of year is usually how you get snow because the cold air of the past week or so is stale and gone for the most part. So yes you need the upper system almost on top of you to get any snow but again to the east in the App mountains is where they can overachieve on these kind of systems.

[tron777]

No changes from the 12Z GFS and CMC from their previous solutions.

[tpweather]

No changes from the 12Z GFS and CMC from their previous solutions.

Those models are more stubborn than lets see that would be me lol.

[dce]

It continues to amaze me how different the plotting is on the Australian MJO plots. Either the Australians are the only ones accurately plotting or they are they only ones inaccurately plotting.

[tpweather]

It continues to amaze me how different the plotting is on the Australian MJO plots. Either the Australians are the only ones accurately plotting or they are they only ones inaccurately plotting.

I agree 100p/c and even more important is how some of the best met's will look at the plots and have a completely different outcome of what phase the mjo is in. I have used it more often in the past several years but when the best met's are not on the same page it gets a little confusing

[tron777]

Great post Doug! Different websites use different data sources and have different calculations. Over the years when I post, I have always tried to use what I thought were either accurate sources or ones that a lot of pro mets. would use. It's the best I can do anyway to try and post as accurately as I can, but it's not perfect.

[dce]

Great post Doug! Different websites use different data sources and have different calculations. Over the years when I post, I have always tried to use what I thought were either accurate sources or ones that a lot of pro mets. would use. It's the best I can do anyway to try and post as accurately as I can, but it's not perfect.

It's certainly not is it!? We were either in phase 7 for the last half of October or phase 6.

[tron777]

Well... The 12Z Euro is now trending towards the GFS for Thanksgiving / Weekend.

[tron777]

Great post Doug! Different websites use different data sources and have different calculations. Over the years when I post, I have always tried to use what I thought were either accurate sources or ones that a lot of pro mets. would use. It's the best I can do anyway to try and post as accurately as I can, but it's not perfect.

It's certainly not is it!? We were either in phase 7 for the last half of October or phase 6.

I go with the Aussie model for consistency sake.

[tron777]

12Z GFS (and the GFS in general in the fantasy range) wants to bring in some very cold air into the picture with a more winter like pattern taking shape, Is the GFS about a weak too early with the idea? The model bridges the -EPO and -NAO ridges together! If something like this were to happen, you're going to get some severe winter weather. Either cold, precip, or both.

Tim, the winter of 76-77 or 77-78 is calling you on line 1 when we had a 500 MB pattern like the one pictured like this one below.

gfs_z500a_namer_65.png

Here's the 12Z GEFS Ensemble Mean and it, along with the EPS show both ridges but they don't connect.

gfs-ens_z500a_namer_65.png

We have ridging over the SW US as well. Still a cold pattern but not as severe as the OP GFS. The Canadian Ens didn't quite connect the two ridges but was closer to that idea then the GEFS and EPS. We may only have to wait a week and a half to two weeks for action if some of this guidance is right.

[dce]

It looks so though the Euro has finally caved to the slower GFS/CMC solution for this weekends storm.

[Bgoney]

It's also a good idea to follow the Himawari satellite system to know if the models are correct on MJO position.

[tron777]

48 here and at CVG today. 50s tomorrow and Wed. Thanksgiving and Black Friday if today's trends are correct, are telling us to change our forecast. I will wait until tonight's runs and maybe 12Z tomorrow then we should have a good idea by then.

The 18Z GFS has a few light showers with a dying front Thurs night / Black Friday, not a big deal. We get wet Sat night and Sunday once the southern low comes in. Could see an inch of rain out of this easily if this solution is right. Not looking good for wintry prospects at this time. Low end risk of seeing frozen precip.

[tron777]

SOI keeps bouncing up and down recently. I wonder if a stormier pattern isn't in the offing for December? -EPO, -AO, -NAO, Neutral to -PNA and MJO Phase 7. So you'd have 3 out of the 4 teleconnections in a favorable state fighting off a SE ridge. That would be a stormy pattern, maybe even a gradient pattern. Where the cold / warm intersect will probably be our forum area as it usually is. I'll gamble with this look though.

[dce]

SOI keeps bouncing up and down recently. I wonder if a stormier pattern isn't in the offing for December? -EPO, -AO, -NAO, Neutral to -PNA and MJO Phase 7. So you'd have 3 out of the 4 teleconnections in a favorable state fighting off a SE ridge. That would be a stormy pattern, maybe even a gradient pattern. Where the cold / warm intersect will probably be our forum area as it usually is. I'll gamble with this look though.

Especially with the amount of cold air that has been and continues to be on our side of the globe.

[tron777]

SOI keeps bouncing up and down recently. I wonder if a stormier pattern isn't in the offing for December? -EPO, -AO, -NAO, Neutral to -PNA and MJO Phase 7. So you'd have 3 out of the 4 teleconnections in a favorable state fighting off a SE ridge. That would be a stormy pattern, maybe even a gradient pattern. Where the cold / warm intersect will probably be our forum area as it usually is. I'll gamble with this look though.

Especially with the amount of cold air that has been and continues to be on our side of the globe.

Exactly Doug. I'm optimistic on December this year, despite the potential of it starting on the mild side. No way it's going to be like last year. The mid December period keeps showing up with a lot of blocking on long term ensemble guidance so hopefully that materializes when we get closer in real time.

[Bgoney]

The process of a complete air mass exchange across the country in progress. Yesterdays winds still had a cold bite to it, but with the high close by today winds die down and some nice getter-done days ahead. Thanksgiving looks dry atm until very late into Friday with light rain chance. Sat/Sunday have plenty of question marks with an upper level low with no particular place to go meandering close by. Still not buying heavier amounts , right now a good starting point for me for the whole holiday weekend is .25"-.75" for AVLAND region.

[tpweather]

Good Morning and I see the Euro is on board with the gfs for later in the week and weekend. So yes we get some rain in here late Thanksgiving into Friday but with the upper system staying off to the southwest the changeover to snow is not looking good and that part of the forecast I will miss badly. I thought the return of moisture an a upper system would worked together and yes by sometime later Saturday that will happen but to much in the way of mild air way up in the atmosphere so unable to bring cold air to the surface and all you get is rain. Rainfall totals is the next item to address and over the past 3 months lower has been the way to go but I believe the STJ is getting active plus the GOM is loaded. So totals imo should be in the .5-1.0 for most folks. The biggest problem for higher totals is over the weekend lift is not as good however there should be a warm front to the south so some overrunning of precip but again we will be somewhat cooler Saturday I am not sure if the temp difference is enough to get a heavy overrunning event.

Long term still looks good as a milder period is in store for a few weeks but this will bring stormier weather as well. So I expect several chances for rainfall but folks in the northern and central plains look to get a decent snow pack. This is key later when the pattern turns colder in December as most signs point to cold and if the STJ continues to be active things could get interesting. Yes we need the correct timing with the cold and precip but we will worry about that in a few weeks.

Les can we ever see another winter like 76/77 and 77/78 and hopefully that happens one day but of course we need the perfect storm. Those seasons we have a weak El Nino so the STJ was active and had a broad trough over much of the USA and once the snow pack built up earlier to our west the cold air had a nice highway and with the STJ active it was not overtaking the pattern as you see with a stronger El Nino.

What was wild during those two winters was the southwest wind that brought moisture over a cold surface and this gave us several heavy snow events. So my guess is do we have a STJ that sort of over performs during a La Nina though is the La Nina dying during this winter.

The good thing is storminess has pickup up over eastern China and Japan in recent days and many times this is a sign that the mainland USA will become busier in terms of storm systems in the next few weeks.

Cold is expected to once again build up in northern Canada while Siberia will of course continue to have cold but not the coldest to average and if we can tap some of the coldest air in the NH easier than a normal winter this helps in getting more winter type events in the USA.

[tpweather]

Bgoney had a great post the other day in stating we had the very warm first part of the month and a very cold middle of the month. So at the moment we are around 1/2 degree below normal for the month which is imo is normal as anything within 1 degree either way is normal. What happens the final 10 days of the month and looks like we will end up milder and mainly because nighttime lows should stay up as more moisture is getting involved with the pattern. So by the end of the month we may end up normal but the month has been anything but normal expect for the final 10 days which is about dead on for this time of year as high temps are usually near 50 and lows in the low 30's Precip we are below normal but have a chance to catch up some before the end of the month.