Converged on a 12/21/2024 coastal storm, however ... much higher than normal uncertainty relative to very shortterm. May need nowcast for impacting east/SE regions

[WxWatcher007]

43 minutes ago, CoastalWx said:

Close call again. That primary s/w is explosive, and that effing initial s/w off the SE coast ruins a MECS. Gah.

 

42 minutes ago, ORH_wxman said:

Yeah its honestly probably costing us double digit snowfall...not an exaggeration. That shortwave is potent....that would be a classic.

“Tenor of the season”

[Snowcrazed71]

1 minute ago, UnitedWx said:

100%! I was hoping it would be a fad for most people however it seems like only 25% of us can't stand it anymore. And thanks, you said tuna sandwich now I'm craving one

It's funny, my close friends and my family will always ask me, " Hey I saw this on Facebook or hey I saw this online showing a big snowstorm " I just tell them pay no attention to those because they're just weather enthusiasts that like hype something that's just a low probability. But they do ask me for my opinion LOL

[ORH_wxman]

25 minutes ago, 40/70 Benchmark said:

This is what irritates me...we have people in the ENSO thread taking a victory lap claiming that the stronger PAC that has been so prevalent since 2015 is the reason we aren't getting a snowfall. I mean, it certaintly doesn't help, but this is more just a SW spacing screwgie. I guess indirectly the jet makes that more likely, sure...

There's always a lot of over-confidence in attribution to failed events on the sub-longwave scale.

 

[Prismshine Productions]

38 minutes ago, ORH_wxman said:

Yeah or even if that southern stream would weaken a bit....the NMB guidance actually weakened it enough so that more of the baroclinicty was focused near the main shortwave so it tries to blow up a coastal....still not fully clean, but it would be shovelable snow for most of SNE and prob warning snow for your area.

http://www.meteo.psu.edu/ewall/ETAEAST_12z/etaloop.html

 

12z Reggie was damn close too

[brooklynwx99]

27 minutes ago, 40/70 Benchmark said:

This is what irritates me...we have people in the ENSO thread taking a victory lap claiming that the stronger PAC that has been so prevalent since 2015 is the reason we aren't getting a snowfall. I mean, it certaintly doesn't help, but this is more just a SW spacing screwgie. I guess indirectly the jet makes that more likely, sure...

i've stopped bothering, honestly. if there's La Nina influence, it's warm. but if there's lingering El Nino influence, it also makes it warm. Pacific jet extension? you guessed it, warm. but if we see the jet retract? well, that's just the La Nina base state warming us up again

[UnitedWx]

Just now, Snowcrazed71 said:

It's funny, my close friends and my family will always ask me, " Hey I saw this on Facebook or hey I saw this online showing a big snowstorm " I just tell them pay no attention to those because they're just weather enthusiasts that like hype something that's just a low probability. But they do ask me for my opinion LOL

Same here. Just like people who look at their weather app and see a raindrop so they'll tell everybody it's going to rain all day

[ORH_wxman]

RGEM was pretty damned close too...actually has decent snowfall in E MA, but not sure I buy it as the main CCB is still a bit east. Almost like a little CF enhanced area from onshore flow.

[vegan_edible]

Just now, brooklynwx99 said:

i've stopped bothering, honestly. if there's La Nina influence, it's warm. but if there's lingering El Nino influence, it also makes it warm. Pacific jet extension? you guessed it, warm. but if we see the jet retract? well, that's just the La Nina base state warming us up again

certain posters have unlocked the key to mental gymnastics with concentric thought circles that only lead to warmth. 

 

[weathafella]

I thought NAM was chasing convection off of the SE coast possibly messing up this run.

[ORH_wxman]

Just now, weathafella said:

I thought NAM was chasing convection off of the SE coast possibly messing up this run.

It's that shortwave in the southern stream....so I think it's real. But if it verifies weaker, then we have a chance at something bigger.

[dryslot]

Ray gets his Jack on the Reggie.

[Typhoon Tip]

41 minutes ago, 40/70 Benchmark said:

This is what irritates me...we have people in the ENSO thread taking a victory lap claiming that the stronger PAC that has been so prevalent since 2015 is the reason we aren't getting a snowfall. I mean, it certaintly doesn't help, but this is more just a SW spacing screwgie. I guess indirectly the jet makes that more likely, sure...

they may be indirectly correct ... though it's not abundantly clear given your description here, whether or not they actually know that - sounds like they're labeling something intuitive but the current pac circulation mode is something else.

"why" this particular storm is behaving the way it has been, in guidance:   it is far more likely that the longer term frequency of the mjo, wrt to the mid and high latitude circulation mode(s) between the n arc of the pac medium ... spanning down stream across the n/a mid latitude continent, are in destructive interference.  

they are in conflict.

the mjo was quite vigorous as it passed recently 3-4-5-6.  those correlate just about diametrical to the -(wpo/epo) and +pna pattern motif.     you know, the mjo is not forcing the pattern, but does serve to amplify or deamplify.  it is a modulator in that sense- i realize i've gone over this a dozen times so this is just for making the point here. 

what we're seeing with a ho-hum western ridge presentation is just about 95% ( colloquially...) of why this thing is having trouble amplifying as it is approaching the bottom of the trough ... i'm personally very highly confident that the primary sensitivity in why this is struggling to do so, is the handling over western n/a.  that western ridge really appears almost arithmetically a medium between the mjo's negative modulation input, on top of a strong +d(pna) leading this event.  

the very recent subtle improvements in western track/impact implications and so forth, appear to be a stronger wave relay off the pacific - wave centric.  maybe that will be enough, maybe it won't...

the phase 5 mjo timing with this +d(pna) is just as likely to happen in 1950 as it is in the years since 2015.   aside from all that...the excited jet velocity and compression and all that began prior to 2015 anyway.

[CoastalWx]

2 minutes ago, dryslot said:

Ray gets his Jack on the Reggie.

Jack was east of him, he'd be pissed.

[Prismshine Productions]

Just now, CoastalWx said:

Jack was east of him, he'd be pissed.

boston snap the 4" streak tho

 

[Prismshine Productions]

12z ICON following Reggie and the NAM,,,

[CoastalWx]

2 minutes ago, Prismshine Productions said:

boston snap the 4" streak tho

 

I think that would be west of them verbatim.

[Prismshine Productions]

Just now, CoastalWx said:

I think that would be west of them verbatim.

oof

[ORH_wxman]

There's definitely a CF that sets up prior to any coastal approaching the area....RGEM and 3k NAM are kind of similar with it....right over 128 or thereabouts. You can see the onshore flow and then almost northerly or NNE flow on the other side of it with temps 6-8F colder. If things set up correctly, you can get a narrow band of enhanced snow with a few inches on the cold side....

 

SE MA wants the main CCB to back into their area...if that happened, they would flash to heavy paste.

[CoastalWx]

2 minutes ago, ORH_wxman said:

There's definitely a CF that sets up prior to any coastal approaching the area....RGEM and 3k NAM are kind of similar with it....right over 128 or thereabouts. You can see the onshore flow and then almost northerly or NNE flow on the other side of it with temps 6-8F colder. If things set up correctly, you can get a narrow band of enhanced snow with a few inches on the cold side....

 

SE MA wants the main CCB to back into their area...if that happened, they would flash to heavy paste.

Yeah that CF is classic. I think it's a real feature for sure. Probably sets up there for a few hours at least and slowly sags SE.

[ORH_wxman]

2 minutes ago, CoastalWx said:

Yeah that CF is classic. I think it's a real feature for sure. Probably sets up there for a few hours at least and slowly sags SE.

850 temps are like -9C too....so I think we'd have decent low level snow growth if we can get that light easterly flow over the top of the sfc front. This type of setup isn't super common, but we see it occasionally. You can get a surprise 1-3" on the cold side of the front.

I remember we had a similar thing happen on 12/15/95 prior to an IVT system that set up later that night....during the day, we had this easterly flow that dropped a couple inches to the west of Boston. Then everyone got a few more inches from the IVT that night as the boundary slide ESE.

[ROOSTA]

4 minutes ago, ORH_wxman said:

There's definitely a CF that sets up prior to any coastal approaching the area....RGEM and 3k NAM are kind of similar with it....right over 128 or thereabouts. You can see the onshore flow and then almost northerly or NNE flow on the other side of it with temps 6-8F colder. If things set up correctly, you can get a narrow band of enhanced snow with a few inches on the cold side....

 

SE MA wants the main CCB to back into their area...if that happened, they would flash to heavy paste.

I forgot the year. A strong clipper swooped down and went to town, literally bombed out. You, Phil and Messenger where barking like dogs chasing squirrels. A BOMB if I recall?  

[dryslot]

Potential for a big one is there but you get a s/w to muck it up, You hate to see it.

[ORH_wxman]

GFS showing it too now much stronger than before. Shortwave looks better this run too.

[Prismshine Productions]

12z GFS continues the suite trend...

[dryslot]

More regression on the 12z GFS, SLP further east then 06z.

[40/70 Benchmark]

28 minutes ago, ORH_wxman said:

There's always a lot of over-confidence in attribution to failed events on the sub-longwave scale.

 

Like I said, I am sure the faster Pac jet can make destructive interference more likely, but its not as if its entirely prohibitve.

[Prismshine Productions]

Just now, dryslot said:

More regression on the 12z GFS.

actually it was not

[ineedsnow]

gets northeast ma pretty good but main low moved east

[CoastalWx]

Too little too late.

[dryslot]

Just now, Prismshine Productions said:

actually it was not

At the surface it was.