December Mid/Long Range Discussion

[Ralph Wiggum]

Thing I've learned over the past several seasons....a good PAC can overcome a meh Atlantic. And more often than not a good Atl with a crud PAC does us no good. There are exceptions but I almost always look to the PAC side first before seeing what the Atl is doing. 

[Chris78]

5 minutes ago, Ralph Wiggum said:

Thing I've learned over the past several seasons....a good PAC can overcome a meh Atlantic. And more often than not a good Atl with a crud PAC does us no good. There are exceptions but I almost always look to the PAC side first before seeing what the Atl is doing. 

I agree. We don't want a raging +++ Nao but if it's slightly positive we can work with it especially as we get deeper into winter.

But I'm not necessarily big dog hunting either. If we want a HECS then sure. We need a - Nao and AO.  I just want some damn snow lol. Enough so that my kids can go sledding.

[aldie 22]

I miss the old fashioned 2-4" 3-6" snows don't get me wrong i love the big dogs but a couple of 3" storms would go a long way for morale around here I bet.

[wxdude64]

3 minutes ago, aldie 22 said:

I miss the old fashioned 2-4" 3-6" snows don't get me wrong i love the big dogs but a couple of 3" storms would go a long way for morale around here I bet.

^^ This 100% ^^

[TSSN+]

One serious deluge. Anyone opening a thread? 

[Ji]

30 minutes ago, dallen7908 said:

Yes, the PNA is positive during the last week of December but the NAO also remains positive.   On the positive side, approximately 25% of the EPS and GEFS members show a neutral or slightly negative NAO during the last portion of the last week of December.  I can't remember the last time there was anything to track during the December 27 - January 1st period.   Hopefully, the ensemble 500 means are on to something. 

yea usually that is a death week--

[Solution Man]

2 minutes ago, aldie 22 said:

I miss the old fashioned 2-4" 3-6" snows don't get me wrong i love the big dogs but a couple of 3" storms would go a long way for morale around here I bet.

Those events were good ole days. How many days since a Winter Storm Watch or Warning for the DC Metro. I know west of Hwy 15 has had a few. I think we are jaded.

[brooklynwx99]

1 hour ago, CAPE said:

Yeah a few runs in a row now. A lot would have to go right timing wise with no help in the NA, esp for the lowlands, but something to keep an eye on.

what’s interesting is that the central Canadian ridge actually leads to HP in a good spot since it leads to NVA aloft. so, it can provide confluence even if it’s in an unorthodox way

[Eskimo Joe]

7 minutes ago, Solution Man said:

Those events were good ole days. How many days since a Winter Storm Watch or Warning for the DC Metro. I know west of Hwy 15 has had a few. I think we are jaded.

Quick search shows no Winter Storm Warning for DC since 2019. Could be wrong.

[cbmclean]

29 minutes ago, Ralph Wiggum said:

Thing I've learned over the past several seasons....a good PAC can overcome a meh Atlantic. And more often than not a good Atl with a crud PAC does us no good. There are exceptions but I almost always look to the PAC side first before seeing what the Atl is doing. 

Yeah but based on PSU's findings it appears that the NAO may be more important in the average west-based Nino because it helps modulate the alwaye Nino tendency to inject Pacific air into NA.

I agree that in Nina the PAC is an absolute.  If it is flooding us with Pac Puke then forget the NAO.  If we have a nice EPO or PNA ridge, then perhaps the NAO is of less consequence.

[cbmclean]

Actually what I think I have learned is that THE critical factor is always whichever one sucks for us at a given time.

[SnowenOutThere]

6 minutes ago, Eskimo Joe said:

Quick search shows no Winter Storm Warning for DC since 2019. Could be wrong.

What about Jan 3rd 2022? 

[CAPE]

5 minutes ago, brooklynwx99 said:

what’s interesting is that the central Canadian ridge actually leads to HP in a good spot since it leads to NVA aloft. so, it can provide confluence even if it’s in an unorthodox way

It's not there on the GEFS, and the track looks too far N/inland. EPS suggests a track right along/off the coast with HP to the NW, LP over Atlantic Canada. Surface temps are colder. Long way out so plenty can change but we are gonna need some cold for this not to be just another rain event.

[Eskimo Joe]

Just now, SnowenOutThere said:

What about Jan 3rd 2022? 

It was a quick search on the IEMbot website, but that didn't come up as a warning for the District.

[cbmclean]

17 minutes ago, TSSN+ said:

One serious deluge. Anyone opening a thread? 

Man I hate seeing rain in Quebec in mid/late December.

[brooklynwx99]

4 minutes ago, cbmclean said:

Yeah but based on PSU's findings it appears that the NAO may be more important in the average west-based Nino because it helps modulate the alwaye Nino tendency to inject Pacific air into NA.

I agree that in Nina the PAC is an absolute.  If it is flooding us with Pac Puke then forget the NAO.  If we have a nice EPO or PNA ridge, then perhaps the NAO is of less consequence.

i can pretty much guarantee that if we see a strong -NAO there could be a prolific period as long as the Pacific isn’t absolute garbage. we are seeing a strong STJ and zero indication of any persistent SE ridging 

[WxUSAF]

So for argument’s sake, let’s say the ensembles are currently correct and we get a mean trough over us around Xmas or so. How far off is that from expectations 10 days ago? A couple days? Maybe 5 at most? Rough outcome for the never ending torch crowd. 

[Eskimo Joe]

Just now, cbmclean said:

Man I hate seeing rain in Quebec in mid/late December.

Yea it's not a good sign for the winter. Hudson Bay is still somewhat unfrozen and the Great Lakes are largely ice free. If we get a direct discharge of arctic air, the open water will modify the air mass. 

[Solution Man]

14 minutes ago, Eskimo Joe said:

Quick search shows no Winter Storm Warning for DC since 2019. Could be wrong.

Wow

[CAPE]

4 minutes ago, WxUSAF said:

So for argument’s sake, let’s say the ensembles are currently correct and we get a mean trough over us around Xmas or so. How far off is that from expectations 10 days ago? A couple days? Maybe 5 at most? Rough outcome for the never ending torch crowd. 

The narrative will change to 'we told you most of the country would see above average temps'.

[cbmclean]

2 minutes ago, brooklynwx99 said:

i can pretty much guarantee that if we see a strong -NAO there could be a prolific period as long as the Pacific isn’t absolute garbage. we are seeing a strong STJ and zero indication of any persistent SE ridging 

Sure, but that is not what I trying to talk about.  Ralph said "a good PAC can overcome a meh Atlantic".  I agree that can be true for a nice EPO/PNA dominant pattern, especially down in my neck of the woods since the dry arctic cold of a direct -EPO shot can sometimes move the storm track right over me with cold air.

But in an east-based nino a "good" pacific is one that almost always has some tendency inject Pacific air, and the -NAO appears to be critical in modulating that.  So what i am trying to say is that I am not sure a good east-based nino Pacific can overcome a meh Atlantic. 

[brooklynwx99]

Just now, cbmclean said:

Sure, but that is not what I trying to talk about.  Ralph said "a good PAC can overcome a meh Atlantic".  I agree that can be true for a nice EPO/PNA dominant pattern, especially down in my neck of the woods since the dry arctic cold of a direct -EPO shot can sometimes move the storm track right over me with cold air.

But in an east-based nino a "good" pacific is one that almost always has some tendency inject Pacific air, and the -NAO appears to be critical in modulating that.  So what i am trying to say is that I am not sure a good east-based nino Pacific can overcome a meh Atlantic. 

yeah, you’re probably correct there. those years usually don’t have amazing Pacific patterns

[cbmclean]

4 minutes ago, brooklynwx99 said:

yeah, you’re probably correct there. those years usually don’t have amazing Pacific patterns

Well I was assuming he was talking about "nino good" which is good in the sense that it has a strong STJ and promotes east coast troughing, which is great as long as there is enough cold air to mix with the moisture.

If he was just referring to the generic EPO/PNA good then i agree 100%.

[brooklynwx99]

6 minutes ago, CAPE said:

The narrative will change to 'we told you most of the country would see above average temps'.

“actually Nunavut is gonna be +20 so nobody cares if it’s -1 along the EC” as it’s literally snowing 

[cbmclean]

3 minutes ago, brooklynwx99 said:

“actually Nunavut is gonna be +20 so nobody cares if it’s -1 along the EC” as it’s literally snowing 

Speaking of that, has anyone been paying attention to the trends on the JCI (Jet "Chill" Index)?  Are we still on track to get it to calm down a bit so the source regions can start to recover.

[mattie g]

11 hours ago, clskinsfan said:

PSU said something a couple of pages back about it. We get flooded with PAC air constantly now. We will see over the next couple of months if ENSO means anything anymore. 

It's not just the Pacific air itself. It's the flow that blocks the cold from getting out of Siberia (it's been f'ing cold as Dante's hell there), across Canada, and down into our neck of the woods.

We've been dealing with the flow for quite a few years now, but there's nothing to say that it's something that won't change again within another few years.

[WinterWxLuvr]

22 minutes ago, CAPE said:

It's not there on the GEFS, and the track looks too far N/inland. EPS suggests a track right along/off the coast with HP to the NW, LP over Atlantic Canada. Surface temps are colder. Long way out so plenty can change but we are gonna need some cold for this not to be just another rain event.

Wouldn’t that argue that we need a cold push that doesn’t have the steam to make it too far out over those warm waters?

[weatherbook]

56 minutes ago, Eskimo Joe said:

Quick search shows no Winter Storm Warning for DC since 2019. Could be wrong.

D.C. had a winter storm warning on Jan 3, 2022.  I measured about 8" at the Tidal Basin.  It was a classic D.C. snowstorm.

 

[GATECH]

46 minutes ago, Solution Man said:

Wow

How much snow did DCA get from Jan 3, 2022....I am 11 miles south of DCA and got 11" and am pretty sure we were upgraded to a WSW from a WWA.

[brooklynwx99]

30 minutes ago, cbmclean said:

Speaking of that, has anyone been paying attention to the trends on the JCI (Jet "Chill" Index)?  Are we still on track to get it to calm down a bit so the source regions can start to recover.

to be honest, I think that some of the source region stuff is a bit overrated. yes, we would prefer Canada to be cold, but that is usually not the case in El Ninos, even the prolific ones. for example, look at Feb 2010! there was +10-15C air right over SE Canada. made no difference. same with Feb 1987, Canada is torched