• Hello, please take a minute to check out our awesome content, contributed by the wonderful members of our community. We hope you'll add your own thoughts and opinions by making a free account!

Pattern Fail or Fab February 2023 Pattern Thread

griteater said:
Of course, we also want to see the SSW go bonkers and downwell forcefully into the troposphere for a better shot at legit -AO/-NAO (need more time to let that one marinate and see how it shakes out)
Click to expand...
00z runs of the GFS and NASA GEOS models show nice downwelling of the SSW from the upper stratosphere (e.g. 1 mb) to the top of the troposphere (i.e. tropopause, approx 150mb) during the 2/10 to 2/20 timeframe (i.e. via negative NAM values in orange on the images).

Judah Cohen says the model runs that we typically view (GEFS / EPS etc.) become more reliable at predicting the effects of the SSW on the weather pattern once the SSW reaches the tropopause, so around 2/20 on these images. Hopefully, this type of downwelling look continues (it may not).

it1XpEG.png


h2H63mo.png
 
grit, doesn't it really need to get to the 500mb level to really have an impact on the pattern? Forgive my professional curiosity here.
 
griteater said:
A few thoughts....the upper level signal of the MJO (200VP 1st image below) hasn't gotten stuck in the Indian Ocean and Maritime Continent this winter like it sometimes does, especially during La Nina. It has kept on cycling around the equator from Fall thru Winter. But when it's been in 8-1-2 (e.g. late Nov into Dec and in Jan), we haven't gotten the response we're looking for (western ridging).

Moving forward, 8-1-2-3 are all good this time of year historically, and we're about to make another run thru those phases with the VP signal moving east out of the Maritime Continent (2nd image). Will it help to impart western ridging this time or does persistence win out?? Only thing I can throw out here is that we may have, for the first time since Fall, a legit disruption to the persistent lower level La Nina trade winds along the dateline upcoming (3rd image along 180 longitude)...so maybe that helps to shake things up a bit. Of course, we also want to see the SSW go bonkers and downwell forcefully into the troposphere for a better shot at legit -AO/-NAO (need more time to let that one marinate and see how it shakes out)

Pattern discussion beats trying to hold off northward surging 500mb lows and warm noses (I think)

RpSV3gw.png


4Rl8znx.png


67VmdQl.png
Click to expand...
Thanks Grit. Looking at the standard mjo plots, it never really looked like it got into the cold phases this year. Looks like it almost did, then died into the cod. Perhaps the reason we didn't get the western ridging was because the forcing signal wasn't strong enough to force an effect.

And of course, early though it is, it's shown to do the same thing in a few weeks. ?‍? Any thoughts on why we really just cannot hang out in the cold phases the last several years? Or at least with any amplication that makes a difference?

1676052554732.png
 
SnowNiner said:
Thanks Grit. Looking at the standard mjo plots, it never really looked like it got into the cold phases this year. Looks like it almost did, then died into the cod. Perhaps the reason we didn't get the western ridging was because the forcing signal wasn't strong enough to force an effect.

And of course, early though it is, it's shown to do the same thing in a few weeks. ?‍? Any thoughts on why we really just cannot hang out in the cold phases the last several years? Or at least with any amplication that makes a difference?

View attachment 132927
Click to expand...
To be fair we made the best passage possible jan 2022
 
SnowNiner said:
Thanks Grit. Looking at the standard mjo plots, it never really looked like it got into the cold phases this year. Looks like it almost did, then died into the cod. Perhaps the reason we didn't get the western ridging was because the forcing signal wasn't strong enough to force an effect.

And of course, early though it is, it's shown to do the same thing in a few weeks. ?‍? Any thoughts on why we really just cannot hang out in the cold phases the last several years? Or at least with any amplication that makes a difference?

View attachment 132927
Click to expand...
You should just print this out and post it by the computer. That's virtually the predominate configuration of that image every year now.
 
GEFS has a nice warm look by the end of the month and maybe just maybe we dry out a bit!


Sent from my iPhone using Tapatalk
 
SnowNiner said:
Thanks Grit. Looking at the standard mjo plots, it never really looked like it got into the cold phases this year. Looks like it almost did, then died into the cod. Perhaps the reason we didn't get the western ridging was because the forcing signal wasn't strong enough to force an effect.

And of course, early though it is, it's shown to do the same thing in a few weeks. ‍ Any thoughts on why we really just cannot hang out in the cold phases the last several years? Or at least with any amplication that makes a difference?

View attachment 132927
Click to expand...

For whatever reason even in the right phases we don’t manifest the expected outcome. With how wet this Nina has been it’s pretty clear we have to rethink what is “typical” in terms of ENSO/indices/MJO.


Sent from my iPhone using Tapatalk
 
ATLwxfan said:
GEFS has a nice warm look by the end of the month and maybe just maybe we dry out a bit!


Sent from my iPhone using Tapatalk
Click to expand...
GEFS likes to be wrong in the short medium and long range. Warmth on average will continue for now but we continue to get cold troughs mixed into the medium range until a pattern can materialize that can keep the troughs in place out east. Example below of its long range and what ends up verifying as we get closer. Wavy and progressive. But I’m hoping a legit SSWE and better mjo progression can give us something more legit coming late February and into early and mid march. Regardless winter as a whole has sucked as we all know .. think we can still manage something in march though if we can get this stuff to materialize (at least in the upper south east regions) 9D29B123-B405-428E-AF72-3AF2B50BD5CD.jpeg3BEE405D-6B95-4E52-B1C2-7C48FE971504.jpeg
 
griteater said:
00z runs of the GFS and NASA GEOS models show nice downwelling of the SSW from the upper stratosphere (e.g. 1 mb) to the top of the troposphere (i.e. tropopause, approx 150mb) during the 2/10 to 2/20 timeframe (i.e. via negative NAM values in orange on the images).

Judah Cohen says the model runs that we typically view (GEFS / EPS etc.) become more reliable at predicting the effects of the SSW on the weather pattern once the SSW reaches the tropopause, so around 2/20 on these images. Hopefully, this type of downwelling look continues (it may not).

it1XpEG.png


h2H63mo.png
Click to expand...

This is key. Without this occurring, a SSWE is a moot point.


Sent from my iPhone using Tapatalk
 
SnowNiner said:
Thanks Grit. Looking at the standard mjo plots, it never really looked like it got into the cold phases this year. Looks like it almost did, then died into the cod. Perhaps the reason we didn't get the western ridging was because the forcing signal wasn't strong enough to force an effect.

And of course, early though it is, it's shown to do the same thing in a few weeks. ?‍? Any thoughts on why we really just cannot hang out in the cold phases the last several years? Or at least with any amplication that makes a difference?

View attachment 132927
Click to expand...
Those MJO Phase diagrams are based on calculations of 3 fields in the tropics: 1) Location of cloudiness / convection (OLR), 2) Lower level winds (850mb zonal winds), and 3) Upper level winds (200mb zonal winds). Although the MJO has been cycling on a regular basis since Fall, it is true that those 3 fields have remained fairly locked in to an underlying La Nina footprint, so yeah, not seeing big amplitude on the left side of the circle.

That does make me think though of the old GaWx MJO research where he found that the coldest temperatures in the East were typically found when the MJO was within the circle (COD) on the left hand side (i.e. Phases 7-8-1-2). That's what we had in the 2nd half of last January (image below).

Anyway, La Nina + Warm Phases (4-5-6) yields a high probability of Eastern warmth (Retracted Pac Jet and -PNA tendencies). La Nina + Cold Phases (8-1-2) yields a better chance for Eastern cold, but by no means is it a high chance (better chance at extended Pac Jet and -EPO / +PNA tendencies)

K4sFIGK.png
 
CPCs 3-4 week outlook highlights the major uncertainty in the guidance due to the SSWE that will take place along with an MJO moving into a much better and more favorable position for this time of year. There could be little to no affect but they also highlight these sort of changes might not be seen on dynamical models this far out. Keep your eye out on models for late February into early march for sudden changes in the pattern as these events could create a better environment for a more favorable pattern to show up.
 
NickyBGuarantee said:
CPCs 3-4 week outlook highlights the major uncertainty in the guidance due to the SSWE that will take place along with an MJO moving into a much better and more favorable position for this time of year. There could be little to no affect but they also highlight these sort of changes might not be seen on dynamical models this far out. Keep your eye out on models for late February into early march for sudden changes in the pattern as these events could create a better environment for a more favorable pattern to show up.
Click to expand...
If it happens too late, it won't matter how strong the ssw event is unless it's unreal cold.
 
Itryatgolf said:
If it happens too late, it won't matter how strong the ssw event is unless it's unreal cold.
Click to expand...
I believe it’s forecasted to take place very soon. March is fair game as it always is at least for the upper SE regions. MJO goes favorable late February and early march as well. Not too late at all. If this event happened in mid march .. that’s when things are too late and you get a cold rain April
 
You must log in or register to reply here.
Back
Top