so_whats_happening

12 hours ago, 40/70 Benchmark said:

2016-2017 was actually a decent snowfall season in SNE...not great, but not bad....near normal on average, and even better across the southern half of the region.

Yes, I pretty much agree with everything else that you have stated here...I was just speaking to the intensity of la nina. In the early going, this la nina is definitely more of a modoki with the cool anomalies focused west.

NAO should be positive.

One thing that I would like to add is that the PNA and PDO, while generally positively correlated, are not necessarily always lock-in-step....so you need to be careful about assuming a predominantly RNA pattern. Last season for instance, featured one of the most negative PDO seasons on record, yet the mean DM PNA value was only very slightly negative. The pattern was actually mainly PNA after the record RNA month of December. Its also about where you live...here in New England, we do absolutely great with decidedly negative EPO and variable PNA...its further to the south that needs the decidedly +PNA.

This is a fair point they don't always need to correlate. PDO tends to produce a more -PNA regime but not always. I do remember seeing the record -PDO last year while I believe we had a -EPO/+PNA (went to neutral as we pushed into Decemeber) regime at the same time, was pretty impressive to see. Yea we definitely need a +PNA for our classic storms but we can manage pretty well with a -PNA sometimes usually our fun anafront situations. Nothing like going from 50's-60's to heavy wet snow in 24 hours.

15 minutes ago, 40/70 Benchmark said:

I'm not that worried about the intensity of la nina....sure, its going to peak at moderate early this fall, buts its going to be weak for the vast majority of winter.

I could agree with that intensity may not be the issue. It may be where forcing takes place. If we look at 2010-2011 season we went to strong La Nina status but the cold pool was so far west that it actually ended up being beneficial for us in the east. That with the situation of a -NAO pattern present from the solar minimum that was around at the time. The biggest difference between than and this time frame is the east coast waters. Back then waters were warm south of Greenland and rather chilly across much of the east coast. Right now waters are just wayyy too warm across much of the eastern sea board. This promotes a ridging like pattern (normally) which in turn would drive weather systems inland with pushing of the baroclinic zone on the coast or just inland, as you stated very +NAO like regime. That would be in conjunction of - PNA pattern bearing a -PDO sticks around too.

2016-17 was an interesting one had another scenario with the coldest waters in Nino 4 similar to this year (so far) and warming as you went east. The result was a pretty barren snow land of a winter in the mid atlantic, not entirely sure about the NE though ( I would think interior did well that year with how the 500mb pattern setup). The cooling couth of Greenland seemed to help re-enforce the idea of +NAO that season.

I think the biggest concerns for the upcoming winter scenario could be how extensive those warm waters are in the east. Do they reach up to around Greenland and help promote a pseudo -NAO regime at times or do we get a cooling that occurs just south of Greenland giving it +NAO regime? Also how extensive the Pacific ridge would be do we see a scenario of ridging along the west coast or is it more confined to the Aleutians? We definitely do not want ridging along the coast and a +NAO that is just a death spell (11-12).

I would gladly take a 10-11 scenario of -NAO and forcing rather far west where the ridge was near the Aleutians.

10 hours ago, 40/70 Benchmark said:

It is going to be more of a modoki la nina this season, but at as long as it remains relatively weak, which it should, then that isn't necessary an absolute death knell.

There is hope for it but the fact is as we approach fall we 'normally' strengthen the ENSO state whichever it may be and with us sitting at a previous trimonthly of -1.0 already and the subsurface I have concerns. This just highlights the east coast waters well. 

The waters off the east coast and up to nova scotia have just been so flippin warm over the past couple years it really is getting difficult to get true miller A patterns setup feel like the baroclinic zone has just been setting up over the coastal plain rather than offshore. Im not liking how far west based the Nina is, if I remember correctly 2011 was the last west based Nina and winter was well... Feel the eerie 2011 vibes right now with SST configuration in the tropical pacific. See how it plays out.

DCA _ NYC _ BOS __ ORD _ ATL _ IAH ___ DEN _ PHX _ SEA

+1    +1.2     +1.4    +1.4   +0.9   +2.1     +2.2      +1.1    +1.6

Thanks Roger

2 hours ago, raindancewx said:

If you use Dallas as a proxy for Texas, there are the winters that followed two extremely cold Februaries over the past 100 years, like 2021 and 2022, that were not El Nino winters / near El Ninos. I'm using 47F or colder in February for average temperature as my proxy for very cold.

1948-49, 1964-65, 1966-67, 1967-68, 1980-81.

1948-49 (extremely cold West winter)

1964-65 (very cold Montana, ND. Some cold New England/Rockies)

1966-67 (this is actually one of the most "normal" winters in US history - fairly near average everywhere)

1967-68 (pretty cold winter most of the US, extremely cold West look in December though like 1948-49).

1980-81 (very hot West, cold SE coast)

July is actually pretty close, especially if you add a degree or two for the age of the analogs (they are centered on 1965!). I'm actually planning to use "anti-logs" quite a bit for this year's winter forecast.

I think the low ACE + La Nina + high solar bit of it is going to hold. Not many years like that. So what would be opposite? 2004-05 and 2019-20 are El Nino after El Nino, relatively low solar, with high ACE. Arguably 1969-70 and 2003-04 are opposite too. Widespread inconsistent cold would be opposite - of the anti-logs (i.e. widespread weak cold in 2022-23). I could see Alaska getting pretty cold and then the cold draining into different areas of lower 48 over time. The anti-log look below is like a more widespread, but less intense flip of 2000-01.

When you state anti logs this means (last image as an example) the country as a whole would be slightly cooler than average for DJF with an emphasis of northern rockies and front range to be cooler than the rest? Just trying to clarify.

4 minutes ago, so_whats_happening said:

Lol I mean we have a similar progression so far in MJO this year (maybe a week or two earlier) to last and you see what happened last year we pushed into 1/2 things took off mid august. Will it happen exactly like this maybe not but cant discredit the fact the pattern seems to be going this way.

To add the only thing different from this year to last is we had a weakening La Nina where this year it has maintained itself much longer. Im not exactly sure how that will play out for this year but if we look at the last 3 peat La Nina episodes (final year of it) 1975 and 2000 they both had low ACE ratings but activity didn't pick up until about mid August. Give it like 3 weeks before we start ringing those potential low activity bells.

2 hours ago, ldub23 said:

Well, by all means show  us some  hyperactive  maps. MJO, MJO, Where for art thou, MJO? July? The desert goes all the way till the  heart  of the season. Now  it  looks  like the season wont  begin till after sept  08. Is  it safe to say that August isnt going to be sideways, unless  you are  looking at a  calendar  upside down and August  in the Atlantic resembles  February. What that  map tells  me  is we will see a few  weak nothings try to spin up just  off the african coast then die  of thirst as they hit the  Sahara or  waves will come  off too far  north to mean anything to anyone. Please i hope for  an el nino next season, it cant be worse than the  last  2 seasons. We can still hang  our  hatts  on the  possibilty  of a  1 storm season and something  managing to find a window  of  moisture in a sea  of  sand. I think CSU  comes  out with an update  on Aug 04. Much lower  numbers  coming.  I still think the European heatwave will be seen by forecasters  like CSU for the reason the season died.

Lol I mean we have a similar progression so far in MJO this year (maybe a week or two earlier) to last and you see what happened last year we pushed into 1/2 things took off mid august. Will it happen exactly like this maybe not but cant discredit the fact the pattern seems to be going this way.

It looks like we have gone into full on step function mode via the volume chart. Next leg down mid 2020's with the looming El Nino?

Seem to be reloading

Is it possible that with extent numbers still relatively higher than the descending average and choppy ice that we see a quicker cooldown scenario going into fall allowing for a potential of thicker ice as we move into the winter? I assume this would not allow for heat to escape in anyway shape or form from the ocean though.

I know this tends to not be everyone's favorite but this is just abysmal. Mind you we are only about mid July right now too. Still have a solid month of decent melt that can occur. GFS has been trying to push the idea of another ridging episode in the last week or so of July too which may just be the final push needed to melt out Beaufort, ESS, and parts of CAA. Somehow the Atlantic front is still sustaining itself even though it was the weakest portion of the ice starting into the melt season.

Lol I dont think anyone in here besides stormchaserchuck has mentioned el nino. A gradual waning though for sure seems to be in the picture as we move into winter but I have my doubts we maintain anything more than cold neutral through winter even with this incoming burst. Nino 4 will be the last to warm so it seems while areas in 1+2 and 3 will be a bit back and forth for the rest of summer into fall, 3.4 will be tricky with a balancing affect. 

DCA _ NYC _ BOS __ ORD _ ATL _ IAH __ DEN _ PHX _ SEA

+1.9     +1.8    +2.1    +1.5    +1.4    +1.8    +2.4   +1.6    +0.9

Ain't looking good with another round of warmth showing up after the 4th of July across Alaska and the very northern reaches of Canada.

So at this point we are going with the idea of nino 4 holding on to the cold still while 1+2  and 3 should start to warm up slowly and work west over time. Nice move in the upper levels taking place. So probably not quite making third year La Nina status..

DCA _ NYC _ BOS __ ORD _ ATL _ IAH ___ DEN _ PHX _ SEA

+2.1   +1.9    +1.6     +0.6    +1.1    +0.8     +1.3    +2.4    +0.4 

102      101      99       97       100      102      103     121      93

DCA +1.6

NYC +1.5

BOS +1.3

ORD  -0.5

ATL  +1.3

IAH  +1.8

DEN  +1.2

PHX  +2.2

SEA  -0.5

DCA +2.0

NYC +1.6

BOS +1.4

ORD +1.3

ATL +2.0

IAH +2.1

DEN +1.0

PHX +1.1

SEA -0.6

On 3/18/2022 at 6:55 AM, etudiant said:

It might be worth checking what the pattern is for the west coast to tease out the differential impact.

California is in a prolonged drought, despite the increase in SST. Are they also getting mostly increases in their night time lows?

Would have to do a little digging around to find out. Might be a thing where temps are being accentuated due to the drought conditions prevailing as deserts while dry do still have some moisture availability so it would help keep the nighttime highs a little warmer while highs a little cooler. Now maybe it is allowing warming to go beyond what it was for daytime highs and not allowing the cool off to occur nearly as much at night? Small changes in moisture out that way probably play large differences in temps.

It is also a cold current versus a warm current so flux is probably not nearly on the level of the east coast. I would assume maybe legit right along the coast may experience a similar setup to the east but further inland I feel would struggle with the net moisture flux especially considering the topography out that way. Feel more often then not winds are blowing from land to sea except along the immediate coast. May totally be wrong in that assumption having never lived out there and experiencing a few days of weather when visiting. 

It is interesting of course because living in the area that has experienced warming I can say easily night time lows are the biggest change we have seen around here. Makes sense with it correlating to ocean heat flux increasing. Basically we are getting more low level moisture to stick around longer/ be replaced more frequently thus locking in higher temps especially at night versus daytime which don't get me wrong has increased but not on the level of nighttime temps in all seasons. I would love to see a study showing the differences to confirm that most of the warming has occurred via nighttime vs daytime or whether it truly is a balance of both and at what times of the year it is most likely to occur (my guess would be fall showing higher daytime peaks and warmer nights in all seasons but winter being the largest change).

So for those that didn't watch:

Increase in atmospheric CO2 --> higher SST (globally and locally) --> slowing of AMOC/ building up of NW Atlantic warmer waters --> changing jet pattern enhances this mode change and compounds the situation more for warming

We have seen the change of more interspersed snowfalls across the Mid Atlantic, higher snowfall totals when we do get those big systems to occur, and overall snow-water equivalent levels well above average over the region as well as the NHEM as a whole.

Having more ridging potential further in the NW Atlantic is a blessing sometimes and can be a big curse. In winter it is beautiful as it would allow for a further west trough allowing us to be near that baroclinic zone for these monster storms to occur. Of course the caveat is the issues that come in the summer time with tropical activity. This further NW Atlantic ridging promotes steering currents into the eastern US more so than the Gulf States, not to say these regions won't get hit, but the frequency of east coast hits may very well go up in the future do to this.

I distinctly remember growing up in the 90's (in SEPA) we had some pretty decent drought years and during the summer we would be rather warm during the day and had many years with some really dead grass in the yards because of the lack of rain and heat that occurred. It seems around 2000-2005 area things flipped a bit we started to introduce more wet summers with less intense heat. Pretty difficult for us to push 100 outside of what the heat island metro areas produce. Flora has been going crazy in the region over the last 10 years it seems, we seem to have ripe conditions for a subtropical feel come late spring early summer, my backyard specifically is constantly on jungle watch with how quickly everything grows. Interesting stuff!

DCA +2.1

NYC +1.7

BOS +1.2

ORD +1.1

ATL +3.4

IAH +2.4

DEN +1.2

PHX +1.3

SEA -0.6

I have a bad feeling about the Arctic coming up this summer. Early season conditioning taking place while the Atlantic front is just a mess overall at or less then 1m thick ice over that way. With everything besides the end of January storm being about on par for a season it looked like things were maybe setting up for a better year. Hope this doesn't play out as such.

The two that have surprised me most by far is IAH and SEA.

22 hours ago, StruThiO said:

MJO is emerging in the Indian Ocean and constructive interference with Nina is beginning. The trades have returned; you can say goodbye to this downwelling Kelvin wave

 

Complete opposite of what you want to see if you were rooting for an El Nino. Maybe next year?

Hmm maybe La Nina modoki to finish out the last year? I keep feeling like we may still have 3rd year La Nina, it has been kind of playing in the back of my mind for a bit. I had originally thought warm neutral was going to happen going into next winter but continuation of increased trade winds especially being much further west then the last 2 bouts has me second guessing. No coherent MJO wave that moves more than 1 octant in a month has occurred thus far and usually we are seeing some wave movement by now if we were to be going toward El Nino like. Not to mention the IOD is still in negative phase.

Will be interesting to watch.

Last times we have had 3rd year La Nina (1954-56 didn't quite make it into 3rd full year, 1973-76, 1998-2001) Periodicity of about 20-24 years in between each event.