February 2023

[bluewave]

19 minutes ago, Allsnow said:

This winter would have sucked back in 1852. The hostile pac and southeast ridge working in tandem with unfavorable mjo was a death sentence. 

The record WPAC warm pool along with the record NW Atlantic SSTs have combined for the record low snowfall. The record SSTs to our east become our friend when the Pacific becomes more favorable with Atlantic blocking. Provides more energy to the snowstorms like in January 2016 and March 2018. But the MJO forcing shifting away from 4-6 is essential. We can work with warmer winters when the MJO and Pacific becomes favorable. The one thing we can’t get with warmer winters is a challenge to 95-96 and 50” becomes much more difficult. But plenty on the forum will take a warm winter with a favorable Pacific and Atlantic blocking intervals and snowfall in the 30s or even 40s. We saw how the hostile Pacific overpowered the -4 AO back in December along with the near record cold around Christmas. That would have been a snowy pattern for us had the Pacific come on board. So the big question is if climate change will result in more hostile Pacific patterns long term? The global climate models haven’t been very helpful. So we need a longer observation period to be sure.
 

https://www.climate.gov/news-features/blogs/enso/csi-enso-case-missing-central-pacific-rainfall
 

https://www.climate.gov/news-features/blogs/how-pattern-trends-across-tropical-pacific-ocean-critical-understanding-future

 

[nycwinter]

11 minutes ago, Allsnow said:

This winter would have sucked back in 1852. The hostile pac and southeast ridge working in tandem with unfavorable mjo was a death sentence. 

you would not have had these same conditions in 1852.

[weatherpruf]

6 minutes ago, MJO812 said:

Watch we get hammered in March 

Rain doesn't count.

[Brian5671]

9 minutes ago, MJO812 said:

Watch we get hammered in March 

[MJO812]

4 minutes ago, Brian5671 said:

Of course you would post that 

[Allsnow]

Next week depends on the -nao which IMO will probably trend weaker 

[Brian5671]

5 minutes ago, MJO812 said:

Of course you would post that 

.4 of an inch of snow in the park supports the weiner

[MJO812]

3 minutes ago, Allsnow said:

Next week depends on the -nao which IMO will probably trend weaker 

Agree but we don't know about the NAO yet.

[snowman19]

Next week depends on the -nao which IMO will probably trend weaker 

Look out west, still a huge full latitude trough dug into Baja. The same exact issue that’s been there since November. In fact the -PNA is trending stronger the end of this month than it was a week ago. A -NAO did Jack diddly squat for us back in December. Here it is, RNA as far as the eye can see

[brooklynwx99]

7 minutes ago, snowman19 said:

Look out west, still a huge full latitude trough dug into Baja. The same exact issue that’s been there since November. In fact the -PNA is trending stronger the end of this month than it was a week ago. A -NAO did Jack diddly squat for us back in December. Here it is, RNA as far as the eye can see

it's February in a La Nina. this is not surprising

a -PNA/-NAO is also a much better mix in late February into March than it is in December due to the shorter wavelengths

if the -NAO doesn't form, we torch. if it does, it could be a prolific period. no real way to tell as of now, but I'm slightly favoring a -NAO due to the SPV impacts. they do increase the chance of Greenland blocking

[GaWx]

54 minutes ago, brooklynwx99 said:

it's February in a La Nina. this is not surprising

a -PNA/-NAO is also a much better mix in late February into March than it is in December due to the shorter wavelengths

if the -NAO doesn't form, we torch. if it does, it could be a prolific period. no real way to tell as of now, but I'm slightly favoring a -NAO due to the SPV impacts. they do increase the chance of Greenland blocking

 Following the 2018 major SSW, NYC for the period 3/7-4/11 averaged 5 BN and had a whopping 17" of snow. This followed the very mild 2/10-3/6 that was 7 AN. They were able to be this cold and snowy despite an average PNA down at -0.5 for that 36 day period. On the days of the 3 main snows (3/7, 3/21, and 4/2) the PNA was -0.7, -0.8, and -1.8, respectively. They had a -PNA on 24 days, a neutral (-0.25 to +0.25) PNA on 9 days, and a +PNA on only 3 days.

 GFS/GEFS trends through 12Z are clearly going in the -NAO direction late in the runs with a -NAO being suggested by March 1st. The trend is also suggesting that it may start in very late Feb as 25% of the 0Z GEFS members have a -NAO by Feb 27th.

 *Edited for typo

[TWCCraig]

[bluewave]

32 minutes ago, GaWx said:

 Following the 2018 major SSW, NYC for the period 3/7-4/11 averaged 5 BN and had a whopping 17" of snow. They were able to be this cold and snowy despite an average PNA down at -0.5 for that 36 day period. On the days of the 3 main snows (3/7, 3/21, and 4/2) the PNA was -0.7, -0.8, and -1.8, respectively. They had a -PNA on 24 days, a neutral (-0.25 to +0.25) PNA on 9 days, and a +PNA on only 3 days.

 GFS/GEFS trends through 12Z are clearly going in the -NAO direction late in the runs with a -NAO being suggested by March 1st. The trend is also suggesting that it may start in very late Feb as 25% of the 0Z GEFS members have a -NAO by Feb 27th.

 *Edited for typo

I posted this earlier in the thread. Unfortunately, we don’t have the 17-18 snowy and more favorable pattern before this SSW. 

Since the 1990s, snowfall before the SSW has roughly been proportional to after.The best snowfall outcomes for NYC after the SSW already had 10.0” of snowfall before. This will be the first SSW with under 1” seasonal snowfall up to the date of the event. So the snowfall during SSW winters were a product of the greater background pattern. 

I bolded the Feb SSWs with around 6” or lower seasonal before the events occurred.  So far this year has been closest to 01-02 which only picked up a T after the SSW. 1999, 2007, and 2008 were better but still well short of the more memorable SSWs on the list like 2018.
 

https://csl.noaa.gov/groups/csl8/sswcompendium/majorevents.html

SSW dates and NYC before and after snowfall

Jan 5 2021…….10.5….28.1

Jan 2 2019……..6.4…..14.1

Feb 12 2018……19.4….21.5

Jan 7 2013……..5.1……21.0

Feb 9 2010……15.5…..35.9

Jan 24 2009….12.0…..15.6

Feb 22 2008….5.7…….6.2

Feb 24 2007…..4.6……7.8

Jan 21 2006….11.7…..28.3

Jan 7 2004….19.8…..22.8

Jan 18 2003…13.2….36.1

Feb 18 2002…..3.5…..T

Jan 2   2001…..13.4….21.6

Feb 25 1999…..6.7…..6.0

[GaWx]

22 minutes ago, bluewave said:

I posted this earlier in the thread. Unfortunately, we don’t have the 17-18 snowy and more favorable pattern before this SSW. 

Since the 1990s, snowfall before the SSW has roughly been proportional to after.The best snowfall outcomes for NYC after the SSW already had 10.0” of snowfall before. This will be the first SSW with under 1” seasonal snowfall up to the date of the event. So the snowfall during SSW winters were a product of the greater background pattern. 

I bolded the Feb SSWs with around 6” or lower seasonal before the events occurred.  So far this year has been closest to 01-02 which only picked up a T after the SSW. 1999, 2007, and 2008 were better but still well short of the more memorable SSWs on the list like 2018.
 

https://csl.noaa.gov/groups/csl8/sswcompendium/majorevents.html

SSW dates and NYC before and after snowfall

Jan 5 2021…….10.5….28.1

Jan 2 2019……..6.4…..14.1

Feb 12 2018……19.4….21.5

Jan 7 2013……..5.1……21.0

Feb 9 2010……15.5…..35.9

Jan 24 2009….12.0…..15.6

Feb 22 2008….5.7…….6.2

Feb 24 2007…..4.6……7.8

Jan 21 2006….11.7…..28.3

Jan 7 2004….19.8…..22.8

Jan 18 2003…13.2….36.1

Feb 18 2002…..3.5…..T

Jan 2   2001…..13.4….21.6

Feb 25 1999…..6.7…..6.0

 Excellent point. I think as brooklynwx said that it is going to come down to whether or not there is a solid -NAO (say sub -0.5) averaged out in March and early April. The model trend fwiw is going in the direction of a -NAO for at least early March. Keep in mind that despite the prior SSWs, none of the four cases you bolded had a -NAO dominated March:

1999: +0.23

2002: +0.69 

2007: +1.44

2008: +0.08

 Also, in 2018, NYC averaged 7 AN for the period 2/10-3/6 fwiw.

[brooklynwx99]

nice to see a signal for legit blocking and a 50/50 to boot. even though the system on the ECMWF looks like it's going to torch, all of the entrenched HP over the top keeps us cold and leads to a nice front-end thump. this is something we really haven't seen all winter

the 22-24th remains our first threat of this period, and blocking seems to become more of a factor at the end of the month

[bluewave]

39 minutes ago, GaWx said:

 Excellent point. I think as brooklynwx said that it is going to come down to whether or not there is a solid -NAO (say sub -0.5) averaged out in March and early April. The model trend fwiw is going in the direction of a -NAO for at least early March. Keep in mind that despite the prior SSWs, none of the four cases you bolded had a -NAO dominated March:

1999: +0.23

2002: +0.69 

2007: +1.44

2008: +0.08

 Also, in 2018, NYC averaged 7 AN for the period 2/10-3/6 fwiw.

Not sure a -AO or -NAO would have as much impact as the better SSW years this March with how hostile the Pacific continues to be. We had the 2nd lowest December -AO on record back in December. This year is the lowest seasonal snowfall by a wide margin for top 5 lowest December AO years. While a -PNA is less hostile overall in late February and March than December, we would still want to see some Pacific improvement. Perhaps enough for NYC to finally get to 1” or more on the season.
 

December top 5 -AO and seasonal snowfall

2009……-3.413….51.4”

2022…….-2.716….0.4”

2010….….-2.631…61.9”

2000…...-2.354….35.0”

1995………-2.127….75.6”

[HeadInTheClouds]

14 minutes ago, brooklynwx99 said:

nice to see a signal for legit blocking and a 50/50 to boot. even though the system on the ECMWF looks like it's going to torch, all of the entrenched HP over the top keeps us cold and leads to a nice front-end thump. this is something we really haven't seen all winter

the 22-24th remains our first threat of this period, and blocking seems to become more of a factor at the end of the month

CMC and GFS also showing something to watch around the 23rd-24th 

[snowman19]

it's February in a La Nina. this is not surprising
a -PNA/-NAO is also a much better mix in late February into March than it is in December due to the shorter wavelengths
if the -NAO doesn't form, we torch. if it does, it could be a prolific period. no real way to tell as of now, but I'm slightly favoring a -NAO due to the SPV impacts. they do increase the chance of Greenland blocking

IMO this ends up like all the others since November. Huge -PNA trough out west dug into southern CA and the models underestimating the SE ridge. That RNA has been a semi-permanent staple the last 4 months and it’s not going anywhere. The models have been grossly underestimating the SE ridge and the -PNA only to have them get stronger as we move closer in time all winter long. They’ve also shown phantom -NAO’s and 50/50 lows/confluence in the long and medium range only for them to disappear. In fact, they had a phantom -NAO block for early-mid February on the long range runs back in mid-late January. They all disappeared. Color me very skeptical. Not saying it can’t happen but if I’m a betting man, I’ll take the under

[495weatherguy]

8 minutes ago, snowman19 said:

IMO this ends up like all the others since November. Huge -PNA trough out west dug into southern CA and the models underestimating the SE ridge. That RNA has been a semi-permanent staple the last 4 months and it’s not going anywhere. The models have been grossly underestimating the SE ridge and the -PNA only to have them get stronger as we move closer in time all winter long. They’ve also shown phantom -NAO’s and 50/50 lows/confluence in the long and medium range only for them to disappear. In fact, they had a phantom -NAO block for early-mid February on the long range runs back in mid-late January. They all disappeared. Color me very skeptical. Not saying it can’t happen but if I’m a betting man, I’ll take the under

You have been correct all winter-impressive!

[SnoSki14]

29 minutes ago, 495weatherguy said:

You have been correct all winter-impressive!

Saying every winter will be a snowless torch is equivalent to JB saying it'll be cold & snowy every season. 

Dead clock 

[snowman19]

Saying every winter will be a snowless torch is equivalent to JB saying it'll be cold & snowy every season. 
Dead clock 

You are one to talk out of all people here. Dr. Jeckyll and Mr. Hyde. Besides not knowing what you’re talking about you flip flop from one extreme to another like a fish out of water. As fickle as the wind. Stand down

[vegan_edible]

2 minutes ago, snowman19 said:

You are one to talk out of all people here. Dr. Jeckyll and Mr. Hyde. Besides not knowing what you’re talking about you flip flop from one extreme to another like a fish out of water. As fickle as the wind. Stand down

he's back... in full swing!

[SnoSki14]

5 minutes ago, snowman19 said:

You are one to talk out of all people here. Dr. Jeckyll and Mr. Hyde. Besides not knowing what you’re talking about you flip flop from one extreme to another like a fish out of water. As fickle as the wind. Stand down

And you know what you're talking about?

Pulling up random Twitter threads that justify your narrative doesn't make you an expert. 

[bluewave]

SE Ridge still a factor at 240 hrs. Some slightly better east based blocking than the old 360 hr forecast. We would need the gradient to push south of NYC to have a shot at going over 1” in NYC. Otherwise it will be a New England special pattern especially the higher elevations.

 

New run

Old run

 

 

 

[Allsnow]

3 minutes ago, bluewave said:

SE Ridge still a factor at 240 hrs. Some slightly better east based blocking than the old 360 hr forecast. We would need the gradient to push south of NYC to have a shot at going over 1” in NYC.

 

New run

Old run

 

 

 

Ridge always trends stronger when we get closer. You have said this all year. Expect nyc to finish with nothing 

[GaWx]

14 minutes ago, bluewave said:

SE Ridge still a factor at 240 hrs. Some slightly better east based blocking than the old 360 hr forecast. We would need the gradient to push south of NYC to have a shot at going over 1” in NYC. Otherwise it will be New England special pattern especially the higher elevations.

 

New run

Old run

 

 

 

On the 0Z GEFS mean, 25% of the members had a sub -0.25 NAO (what I consider the threshold for an -NAO) already by Feb 27th. With the 12Z GEFS mean being even closer to a -NAO on Feb 27th than was the 0Z mean, I feel that the chance of a -NAO starting in very late Feb as opposed to waiting til the first days of March is increasing.

Edit: Remember that nice looking -NAO on the Euro weeklies from last Thursday that then didn't look as good on yesterday's weeklies? The latest trends are heading back to that Thursday weeklies look.

[bluewave]

21 minutes ago, GaWx said:

On the 0Z GEFS mean, 25% of the members had a sub -0.25 NAO (what I consider the threshold for an -NAO) already by Feb 27th. With the 12Z GEFS mean being even closer to a -NAO on Feb 27th than was the 0Z mean, I feel that the chance of a -NAO starting in very late Feb as opposed to waiting til the first days of March is increasing.

Edit: Remember that nice looking -NAO on the Euro weeklies from last Thursday that then didn't look as good on yesterday's weeklies? The latest trends are heading back to that Thursday weeklies look.

We need a -NAO to suppress the SE Ridge just enough. But not so much that the trailing waves get suppressed. So a bit of a thread the needle to get NYC past 1” on the season. Too weak a -NAO and the frozen stays up in New England. This would lead to a stronger SE Ridge than forecast days 8-15 as has been the story all season. 

https://frontierweather.dtn.com/verification.html

[495weatherguy]

39 minutes ago, SnoSki14 said:

Saying every winter will be a snowless torch is equivalent to JB saying it'll be cold & snowy every season. 

Dead clock 

I respectfully disagree with your assessment.  He gives reasons for his predictions, unlike others who wishcast on here.  

[Allsnow]

6 minutes ago, bluewave said:

We need a -NAO to suppress the SE Ridge just enough. But not so much that the trailing waves get suppressed. So a bit of a thread the needle to get NYC past 1” on the season. Too weak a -NAO and the frozen stays up in New England. This would lead to a stronger SE Ridge than forecast days 8-15 as has been the story all season. 

https://frontierweather.dtn.com/verification.html

No reason to buy into cold and snow as it hasn’t shown up this winter. We have been looking at the same medium range maps all season. You have said this all winter. Don’t buy into this 

[bluewave]

6 minutes ago, Allsnow said:

No reason to buy into cold and snow as it hasn’t shown up this winter. We have been looking at the same medium range maps all season. You have said this all winter. Don’t buy into this 

The only time that it is believable is if it makes it to within 120 hrs. Even during other winters with more snow, models show too much snow beyond 120 hrs. We would have multiple 75-100 seasons if all the post 120hr snowfall verified.