February 2023

[LibertyBell]

11 minutes ago, EastonSN+ said:

I would love to find out the reasoning behind the above. The NAO follows the PNA by a couple days. Can this really be coincidence? Can't be. The NAO follows the RNA like a puppy dog 

 

That might have to do with the west to east situation that Snowman mentioned.  west (cause) -----> east (effect)

 

[EastonSN+]

2 minutes ago, LibertyBell said:

It's definitely abnormal and is happening for the same reason the SE Ridge has been migrating north and sending the warmest weather into New England in the summer.

You really didn't hear about these south based blocks before a few years ago.

 

I think it's likely a result of a strong RNA. I.e. when an RNA is intense the downstream effect is a south based NAO. When the RNA is weak or obviously positive, it's a north based block.

Not concerned as we JUST had a standard block just two years ago so they are not gone.

[LibertyBell]

22 minutes ago, EastonSN+ said:

I agree.

I lived through the 80s and 90s so to me this is normal while 00 through 18 was the outlier.

We get a 20/21 winter every 2 to 4 years while the rest are warm and snowless.

IF IF the warmer waters are static, then an 80s repeat can be historically snowy.

 

If you look at Atlantic SST they were much much colder in the 80s than they are now.  That has to factor in a major way.  The only thing we can be sure about is old analogs will no longer work.

 

[EastonSN+]

2 minutes ago, LibertyBell said:

I think the weather actually moves southwest to northeast, so we get input from the southeast ridge and that is what screws us.

In the case of when there is fast Pacific flow and it does move due west to due east we are screwed because of our low (no) elevation.

You really want to have both latitude and altitude in these kinds of patterns.

 

Yeah but haven't we had strong RNAs without an NAO? Or has every strong RNA had an NAO? Have we ever had a very strong RNA with a NORTH based blocks?

[EastonSN+]

Just now, LibertyBell said:

If you look at Atlantic SST they were much much colder in the 80s than they are now.  That has to factor in a major way.  The only thing we can be sure about is old analogs will no longer work.

 

I am not sold that the SSTs are static. We have to wait a few years to see if they cycle out like El Nino las nina. NOBODY knows now.

[LibertyBell]

24 minutes ago, jm1220 said:

Something I’m curious about is why the NAO blocks keep going south based over the last few winters. That obviously does us no good either since we want the 50-50 low south of the block to create confluence and force the storm tracks underneath us. 

Need to keep track of this and how the sensible weather results change decade by decade under similar blocking scenarios.

 

[EastonSN+]

4 minutes ago, LibertyBell said:

That might have to do with the west to east situation that Snowman mentioned.  west (cause) -----> east (effect)

 

And deep RNAs result in NAO failures.

[EastonSN+]

1 minute ago, LibertyBell said:

Need to keep track of this and how the sensible weather results change decade by decade under similar blocking scenarios.

 

If it was SST driven the 2021 standard blocking would have been south too but it was not.

[LibertyBell]

1 minute ago, EastonSN+ said:

I am not sold that the SSTs are static. We have to wait a few years to see if they cycle out like El Nino las nina. NOBODY knows now.

There are other ways to show what's been going on-- look at the impact on the lobster industry.

The famous Maine lobster industry actually started out near Long Island.  As the waters have gotten warmer those lobsters migrated north.  Eventually that became the Maine lobster industry.  Now as the waters have continued to warm, the Maine lobster industry is dying because those lobsters are now in the Maritime Provinces of Canada.

It's all cause and effect really.

[LibertyBell]

1 minute ago, EastonSN+ said:

If it was SST driven the 2021 standard blocking would have been south too but it was not.

Was that the winter with all that record cold and snow in Texas?

 

[EastonSN+]

2 minutes ago, LibertyBell said:

Need to keep track of this and how the sensible weather results change decade by decade under similar blocking scenarios.

 

What we need to track is the connection between deep RNA and NAO failures and position.

Last year was a great example, deep RNA and south based Blocking, the METS call the NAO bootleg and an atmosphereic furnace and not a true block.

 

[donsutherland1]

How New York City's winters with the least snowfall through January 31st progressed through February:

[donsutherland1]

31 minutes ago, jm1220 said:

Something I’m curious about is why the NAO blocks keep going south based over the last few winters. That obviously does us no good either since we want the 50-50 low south of the block to create confluence and force the storm tracks underneath us. 

It may have something to do with the ongoing marine heatwave in the northwestern Atlantic Ocean.

[LibertyBell]

10 minutes ago, EastonSN+ said:

Yeah but haven't we had strong RNAs without an NAO? Or has every strong RNA had an NAO? Have we ever had a very strong RNA with a NORTH based blocks?

I've not heard of north based blocks unless that's just a conventional block.  We've known about east and west based blocks for a long time, south based blocks became a thing just a few years ago.  I suppose north based blocks must also exist, but maybe they are just the "normal" kind of block?

We've had -PNA with +NAO so the cause and effect scenario must only work under particular circumstances.  Maybe there is something else that is the cause for both of them.

Don's idea of marine heatwaves might be it!

 

[LibertyBell]

1 minute ago, donsutherland1 said:

It may have something to do with the ongoing marine heatwave in the northwestern Atlantic Ocean.

That would also explain the northward migrating SE Ridge and the most extreme heat going into New England and SE Canada during the summer too wouldn't it Don?

 

[donsutherland1]

1 minute ago, LibertyBell said:

That would also explain the northward migrating SE Ridge and the most extreme heat going into New England and SE Canada during the summer too wouldn't it Don?

 

It likely is an important part of that story.

[LibertyBell]

4 minutes ago, donsutherland1 said:

How New York City's winters with the least snowfall through January 31st progressed through February:

This winter is literally a flat line ________________________

Fill in the blank line lol ______________________

 

[LibertyBell]

6 minutes ago, EastonSN+ said:

What we need to track is the connection between deep RNA and NAO failures and position.

Last year was a great example, deep RNA and south based Blocking, the METS call the NAO bootleg and an atmosphereic furnace and not a true block.

 

That makes sense because north of the NAO block it's like a furnace lol.

If you look at classic NAO blocks they screw northern new england and Maine is almost always blowtorching.  If that block moves south, guess what else moves south lol.....

That Maine blowtorch becomes OUR blowtorch!

Actually you want the arctic to be mild because that is north of the block and the cold air that is supposed to be up there comes down here instead.

[LibertyBell]

16 minutes ago, EastonSN+ said:

I think it's likely a result of a strong RNA. I.e. when an RNA is intense the downstream effect is a south based NAO. When the RNA is weak or obviously positive, it's a north based block.

Not concerned as we JUST had a standard block just two years ago so they are not gone.

These will likely cycle back and forth but this marine heatwave issue may be the fly in the ointment in just how far north they can or will get when they do.  Heatwaves always end at some point, but note how oceans always respond much more slowly than the air does, so those marine heatwaves likely last much longer too.

 

[EastonSN+]

In the end, I want to see a south based block when the RNA is weak or neutral more than once. I think there is a connection between deep RNAs and south based Blocking. 

 

[WIN]

1 hour ago, LibertyBell said:

wow to see 71 on this date in 2011!

also:

1989 - Low pressure off the coast of North Carolina brought freezing rain and heavy snow to Virginia and the Carolinas. Snowfall totals in Virginia ranged up to 18 inches at Franklin. Freezing rain reached a thickness of two inches around Charlotte NC. (The National Weather Summary) (Storm Data)

This wasn't the February 1989 storm that dropped almost 20" in Atlantic City was it?  Our big virga storm lol

 

Yes. We were forecast for 5 to 8 inches & got nada!

[SnoSki14]

If the arctic cold pool didn't shrink then this March would play out like 1956. 

[EastonSN+]

4 minutes ago, SnoSki14 said:

If the arctic cold pool didn't shrink then this March would play out like 1956. 

Explain? How deep was the RNA and how strong was the NAO?

Also was there an Aleutian ridge? Was the enso the same? 

[LibertyBell]

12 minutes ago, WIN said:

Yes. We were forecast for 5 to 8 inches & got nada!

That was the first I heard the term "virga" being used.

First bad bust I remember, next was the rainy bust of December 1989, then April 1997, then March 2001, then January 2008 and then February 2010 (first storm).  I don't know if that can actually be considered a bust, but it was super disappointing how close we were from 20 inch snowfall totals and ended up with an inch and a half lol.

In a lot of ways the two big busts of 1989 will always be tops in my mind because I expected a snow day out of one and a weekend of sledding out of the other and got neither.

 

[LibertyBell]

14 minutes ago, SnoSki14 said:

If the arctic cold pool didn't shrink then this March would play out like 1956. 

You mean because of the SSW?

I thought we already had the 1956 analog in 2018

So are you basically saying with a deeper arctic cold pool we would have had a March more like 2018 also?

 

[LibertyBell]

12 minutes ago, EastonSN+ said:

Explain? How deep was the RNA and how strong was the NAO?

Also was there an Aleutian ridge? Was the enso the same? 

Might be easier to just compare it to 2017-18 since 1955-56 was used as an analog for that season.

 

[EastonSN+]

10 minutes ago, LibertyBell said:

Might be easier to just compare it to 2017-18 since 1955-56 was used as an analog for that season.

 

Analogs are ok for a loose comparison. Winters are like snowflakes they will never be identical. Although 01/02 and this year are closer than any 2 winters I can remember. That year had a failed NAO as well.

[EastonSN+]

1 hour ago, Stormchaserchuck1 said:

+EPO is underestimated in the MR/LR. Models have it turning to +EPO while NAO is transitioning to negative. I contend there is still a strong -NAO/+EPO-PNA correlation in play, Not really any chance for snow in that imo. There is some potential that the Pacific could be changing state around March 9th, for one, because of the length of -PNA at that time, when it was strongly transitioning to El Nino in the subsurface back in January. 

Interesting.

[EastonSN+]

This would hurt and be fitting for this year.

[EastonSN+]