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Looking towards the beginning of December


CoastalWx

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Well this period looks to be a transition to torch across the CONUS. Zonal PAC flow over bare ground and then downsloped off the Rockies will allow December to begin warm. It does appear we may escape the worst of the mild weather, but it will turn milder for sure.

Until then, perhaps a very weak system this weekend. The GFS is more bullish with overrunning but the Euro while very dry...does hint at moisture coming off the Atlantic and maybe a period of very light snw or freezing precip.

Beyond that, all eys turn to the Pacific. The hope as laid out numerous times in the other thread is for the PAC to retro enough so that we can pop a PNA ridge out west and bring the cold east. As of now, we may not be in a hurry to see that, however very cold air will ooze into the Plains. With a position like that, it's always possible some of it breaks off in time for a SWFE.

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Here is what I mean about the Pacific. Notice the expressway set up from the Pacific right into the US and the 850 temp anomalies. It's just a CONUS furnace, especially the Plains..but this moves east.

Notice the the Aleutian ridge. That is trying to shove frigid air down the east slopes of the Canadian Rockies. While I can't post the ensembles past hr 240...you can see why you would want a ridge out west. It shuts the Pacific down and allows the cold to move east.

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Things do look a bit more favorable as we get towards the 10th or so (a bit after?)

hopefully that works out.

Though admittedly I haven't seen any of today's guidance

The runs that have more of a PNA ridge end up better...but there has been a huge anomaly north of the Bering straight on just about every ensemble suite, which is good because it will make Canada very cold. It will only take a wiggle here and there to spread that over to us...whether we do it with a PNA ridge or via confluence/low heights developing well off to the northeast ala Dec 2007.

If the PAC NW/BC trough is strong and stuck there, we will torch for a bit, but as it retrogrades, we will probably see some chances. I'm hoping the Atlantic will cooperate a little mor eat some point. That would be helpful. It doesn't even have to be a negative NAO...just put some low heights in the right spot northeast of us...Dec '07 saw that..it had such a massive vortex in the southern Davis straight that it actually kept New England cold.

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Things do look a bit more favorable as we get towards the 10th or so (a bit after?)

hopefully that works out.

Though admittedly I haven't seen any of today's guidance

Although something may happen before the 10th, I think that is a decent timeframe for now. JMHO. I'm still not so giddy about things beyond that, but models also have been off and on. Weeklies do look nice as you saw, but it's possible they may rush a favorable pattern too quickly. While it may not happen as earlier as we thought (no surprise here)..the general theme to sort of slow the Pacific down and bring colder air into the US seems to be there.

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The way the high builds in and then retreats I could see that "over perform"

I looked at soundings, it's sort of dry..but maybe a little weenie effect very light snow or FZDZ in spots even in ern MA as east winds overrun north winds. Would be nice if we could get the mid levels to moisten more.

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why does everyone think it will retrograde? NCEP is inclined to thinking it will progress inland ...eventually into the mid drift of N/A; which that would not be altogether bad in its own rite.

Well this is more for the 11-15 day and beyond. And it's not a definite, we were saying the models were trying to show this. So instead if a vortec over BC, it sort of backs up and changes orientation over the GOA.

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it's an obnoxious retreat after a solid November cold performance. All 4 majors solidly below average for the month, more so than any month spanning back years It's actually been that long. June was flirty exception, otherwise, it's been lewd. But here we recess back to the same old finding a way to be above average ...now during a -AO.

it's like.. challenging science with this bias

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it's an obnoxious retreat after a solid November cold performance. All 4 majors solidly below average for the month, more so than any month spanning back years It's actually been that long. June was flirty exception, otherwise, it's been lewd. But here we recess back to the same old finding a way to be above average ...now during a -AO.

it's like.. challenging science with this bias

Does a Swan make a sound when its muted.
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It's the GEFS, but this shows what you don't want to see...which is the first image, to what you want to see...the second image. Notice the differences in the shape of the height contours. You can see how the second image allows for more polar air to come SE from Canada. There is also a ridge out west facilitating this.That's what we hope for, but that is hr 384.

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We need the EPO. We're Not getting PNA help it seems.

We may break toward a positive PNA by mid December, and it could be way more than currently suggested by the GEFs-based teleconnector progs, too.

There is a strong TC in the west Pac and it's slated to waste no time recurving, once it starts gaining latitude - which hasn't started yet. Obviously the global numerical model suite could not possibly be registering a massive latent heat redistribution force in the outlooks if it isn't even yet being detected.

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Yeah either that or some MJO help would work wonders.

Doesn't look like a GOA death vortex like last year but it's not a great situation with a pretty stable pattern over the N Pac and ostensibly not much to shake it up.

It's interesting because we have such a ridge bridge over the pole, but the dam vortex just is in a crappy position. The longer range outlook started bringing colder air into the US thanks to rising heights over the west and the PV sagging a little south in Canada. Hopefully that's enough cold for a SWFE or something. I just can't tell if it will be delayed or move as modeled. My guess is that it turns somewhat favorable, but maybe we need to be patient. For now I thinks it's more after the 10th.

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It's interesting because we have such a ridge bridge over the pole, but the dam vortex just is in a crappy position. The longer range outlook started bringing colder air into the US thanks to rising heights over the west and the PV sagging a little south in Canada. Hopefully that's enough cold for a SWFE or something. I just can't tell if it will be delayed or move as modeled. My guess is that it turns somewhat favorable, but maybe we need to be patient. For now I thinks it's more after the 10th.

It's frustrating though because we're wasting 15+ days of a beautiful looking ridge bridge but we've just been unlucky with where features have setup.

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Well here is what I see, models are beginning to show signs of a potential Lakes cutter sometime in the 5-6th period. A few of the ensemble members show a frontal low developing along the front, one has it where the front stalls and the low moves up the front, but still keeps warm air over eastern New England as the front stalls, another one has the frontal low bombing out offshore. While it's still 10 days away, it is something to keep us interested in the winter weather possibilities. I always like to keep a busy mind, it helps me with my illness. A busy mind is a good thing for a lot of people and weather is sort of my escape, anyways enough of my story.

It appears during the next -AO stage, we aren't going to get the classic polar vortex over Hudson Bay, Canada and instead have a vortex over GOA. GEFS mean has a piece of that vortex break off and ridging builds behind it while ridging exists out in front over the eastern US, allowing our Great Lakes cutter. With such a recent -AO I could see how this system trends colder, but with a rebounding AO its most likely going to be inland and at least keep the coastline warmer. Regardless another Great Lakes cutter happens around the 9-11th period with another possible frontal wave giving us some snow as it goes out to sea. However it is after this period where the PNA begins to rebound towards positive and we get PNA ridging finally where we need it to allow that cold air to pour down into Canada and the central US, perhaps keeping us somewhat modified cold air, but the arctic is a nudge east and we are in it. This appears to happen by the 11th.

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And let's not think for a second this is like last year. Way different and nobody is canceling winter. Some people have had 12" of snow already. It's a matter of discussing the pattern going forward. Unfortunately, things are kind of slow moving along thanks to some of the issues

previously discussed, but hopefully changing after the 10th and towards mid month.

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