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Stuffing and Snow - Late November Banter and Obs


HoarfrostHubb

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It still turns into an ugly cutter, but it may be a nice mix for the interior...perhaps SWFE like. I actually would run with the idea of an interior mixed event going to rain or something of that nature. If the -NAO was more established, it would probably be a Miller B.

I mention this to Jerry the other day.. The static -PNA, albeit modestly so, with dropping NAO values (EPO as well) are both overrunning signals with potential ice scenarios. It's not surprising to see this this/that sort of solution materialize.

The flow is fast however, so it's harder to imagine a stagnated boundary with steady over-lapping. So perhaps a more general energize flow to work with parlays into deeper fast moving cyclones, but where.

One thing that is interesting is that the wave lengths are so short in the late middle range period, which is both a bit off climate-wise, but also meteorologically because the ambient geopotential gradient is higher than normal. It's hard to imagine 110 Kt balance wind turning synoptic corners across such small spatial medium. The deep south heights don't want to recede (perhaps rooted in the lingering -PNA), such that when the NE Pac flexes a mighty -EPO signal ... that causes heights over west -central Canada (teleconnector) to plummet. ...Normally, the planetary wave numbers/spacing would then have said trough response end up axial in the Great Lakes - and with the NAO going in the tank (west-based nonetheless), a broader deep L/W would be preferred that encompasses much of the OV as well. But those stubborn heights in the deep south are an effective subtropical block, and that squeezes the flow into tighter convolution.

I still believe as I did yesterday that to be somewhat suspect, perhaps correctable - how much I am uncertain, but if at any point over the next couple of day's worth of runs those heights in the deep south are eroded downward I wouldn't be surprise. Time will tell with that... I suppose anomalies relative to anomalies ..etc, occur from time to time, so just because it looks suspect, doesn't mean it cannot happen just the same.

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The more I look at it, the more it may be gradient like heading into the beginning of December. The Aleutian ridge is throwing the cold south on the east side of the Rockies in classic form. What a freezer box for Calgary and down into CO. This will pump up heights to the east, but the -NAO will try to act like a wall and prevent heights from rising to hard by introducing confluent flow overhead. This is where the location of the -NAO will be absolutely key for us.

A strong W based -NAO and we can do okay.

Yeah, out west will be in the freezer.

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I mention this to Jerry the other day.. The static -PNA, albeit modestly so, with dropping NAO values (EPO as well) are both overrunning signals with potential ice scenarios. It's not surprising to see this this/that sort of solution materialize.

The flow is fast however, so it's harder to imagine a stagnated boundary with steady over-lapping. So perhaps a more general energize flow to work with parlays into deeper fast moving cyclones, but where.

One thing that is interesting is that the wave lengths are so short in the late middle range period, which is both a bit off climate-wise, but also meteorologically because the ambient geopotential gradient is higher than normal. It's hard to imagine 110 Kt balance wind turning synoptic corners across such small spatial medium. The deep south heights don't want to recede (perhaps rooted in the lingering -PNA), such that when the NE Pac flexes a mighty -EPO signal ... that causes heights over west -central Canada (teleconnector) to plummet. ...Normally, the planetary wave numbers/spacing would then have said trough response end up axial in the Great Lakes - and with the NAO going in the tank (west-based nonetheless), a broader deep L/W would be preferred that encompasses much of the OV as well. But those stubborn heights in the deep south are an effective subtropical block, and that squeezes the flow into tighter convolution.

I still believe as I did yesterday that to be somewhat suspect, perhaps correctable - how much I am uncertain, but if at any point over the next couple of day's worth of runs those heights in the deep south are eroded downward I wouldn't be surprise. Time will tell with that... I suppose anomalies relative to anomalies ..etc, occur from time to time, so just because it looks suspect, doesn't mean it cannot happen just the same.

I've noticed that as well regarding the south. There is also a pretty good STJ moving into Mexico and Gulf of Mexico too and I wonder how much if any will be compressed. Anyways, interesting times ahead I think.

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Yeah, it looks like NCEP echoes my own sentiments, just not going as in depth:

THE MOST COMMON ELEMENT OF D+8 MULTI-DAY MEANS FROM AVBL

MDLS/ENSEMBLE MEANS IS A STG POSITIVE HGT ANOMALY CENTER NEAR THE

BERING STRAIT... WITH TELECONNECTIONS SUPPORTING RELATIVELY LOW

AMPLITUDE FLOW OVER THE CONUS.

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I've noticed that as well regarding the south. There is also a pretty good STJ moving into Mexico and Gulf of Mexico too and I wonder how much if any will be compressed. Anyways, interesting times ahead I think.

Yeah, and it means a big difference in how that handling impacts discrete events. If the anomaly works as majestically as some of these recent operational runs would have it, then cutting lows into/through 60 dm cold thickness walls would have to be plausible - it just all looks daffy. I feel pretty comfortable that something breaks down there - I'm just not sure which. I think the predominating signal is the -EPO/-NAO onset as it simply has had more residence in the runs going back further. Ha, it's almost as though the models wanted to vet the blocking but then went, "oops, what about the deep south".

As NCEP also mentioned in their prelim chit-chat, less amplitude is teleconnected - which is a round-about way of agreeing with us. You just don't normally see 10 isopleths between Edmonton and Dallas with 3 distinct L/W between California and Nova Scotia. By experience, nor teleconnections would support.

Interesting.

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Is this pattern similar to december 08?

Well here is Dec 2008. The Aleutian ridge is definitely there along with a nice Scandinavian ridge. The second half of the month featured more of an Aleutian ridge with a strong SE US ridge. The month began with high heights in the GOA and all over AK.

post-33-0-77948400-1353346729_thumb.gif

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FWIW

DT

*** ABOUT POSSIBLE NOV 29-30 WINTER EVENT FOR THE NORTHEAST US ***

Ignore the 12z GFS model today. Its crap. Use the GFS ensemble... this image is from the PSD GFS ENSEMBLE... it shows the JET STREAM pattern for LATE NOV 30-DEC 1...

the big "L" off the Northeast coast is the Piece of energy that COULD develop into a winter storm for the Northeast...

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I know everyone is interested in the potential for some kind of storm on or just after the 28th. But I am becoming rather interested in the potential snow showers/squalls this weekend. I know I wouldn't mind a good snow squall. Haven't seen one in a while myself.

Agreed - WINDEX sort of appeal to that. It's been signaled for many runs, but the average poster is hooked on the big ticket events so these smaller deals tend to not be noticed.

I did mention yesterday that the 06z run of the time had a stripe of impressive frontogenic forcing from ALB to PWM. That would be more organizing cyclogen, however.

I recall many more years than not, a WINDEX/squally passage herald in a colder regime and eventual storminess -

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I know everyone is interested in the potential for some kind of storm on or just after the 28th. But I am becoming rather interested in the potential snow showers/squalls this weekend. I know I wouldn't mind a good snow squall. Haven't seen one in a while myself.

Yeah it is a potent mid-level feature. I would think minimally the Berkshires and points Northeast might get some snow showers

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This is a consistent signal in GEFS. However, 1993-94 snow was mainly from overrunning events, in tht case, NAO was positive but the ak ridge was in steroids. In this case, one has to hope for better NAO.

overrunning is boring. even pdII was boring to me

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Agreed - WINDEX sort of appeal to that. It's been signaled for many runs, but the average poster is hooked on he big ticket events so these smaller deals tend to not be noticed.

I did mention yesterday that the 06z run of the time had a stripe of impressive frontogenic forcing from ALB to PWM. That would be more organizing cyclogen, however.

I recall many more years than not, a WINDEX/squally passage herald in a colder regime and eventual storminess -

I didn't look to in depth, but the ECMWF and GFS are quite similar and the Total Totals for the event are rather impressive at this point.

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