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Late November/Early December upcoming wx.


CoastalWx

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If it has any support at all from the Euro the NAM can be safely disposed of like a used jimmy.

The GFS is awfully attractive.

you're/we're gonna want that NAM solution though as the GFS low levels are significantly milder during the late afternoon/evening so most of the precip falls as rain before a short-lived mix. NAM would definitely be a better shot at an hour or three of actual snow.

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It depends on the type of thermal profile...on 2/24-25/10, I had nearly 12" in ORH at 900+ feet while weatherMA and ma_blizzard in Shrewsbury both at around 450-500 feet had like 4-5"...so a difference of like 7-8" over 450 feet.

Early on in the storm, I bet Collinsville at 540 feet had a good head start since it was a steep lapse rate in the lowest levels. It evened out later in the storm, but it still matters. The mesoscale banding as Ryan said certainly makes a difference too, but I've seen just 300-400 feet make a huge difference before...it just takes the right low level thermal profile.

Sorry for spawning an OT convo in here..but yeah I have to agree. Like I mentioned in a PM to you a couple weeks ago, even the 180 feet between my parents' places made an incredible difference..although it seemed Waterbury got into the dry slot somehow. It's really going to bother me for a long time that I won't ever know what I got here..at least I have a decent ballpark estimate though.

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you're/we're gonna want that NAM solution though as the GFS low levels are significantly milder during the late afternoon/evening so most of the precip falls as rain before a short-lived mix. NAM would definitely be a better shot at an hour or three of actual snow.

The NAM clown map jackpots you with 1.5 new, congrats

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you're/we're gonna want that NAM solution though as the GFS low levels are significantly milder during the late afternoon/evening so most of the precip falls as rain before a short-lived mix. NAM would definitely be a better shot at an hour or three of actual snow.

We should keep in mind that the GFS low levels tend to bias warm too...but it might be a catch 22 where the sooner the colder air comes in, the drier the low levels get inhibiting precip.

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Sorry for spawning an OT convo in here..but yeah I have to agree. Like I mentioned in a PM to you a couple weeks ago, even the 180 feet between my parents' places made an incredible difference..although it seemed Waterbury got into the dry slot somehow. It's really going to bother me for a long time that I won't ever know what I got here..at least I have a decent ballpark estimate though.

This past storm...9" for me (475')....11" up 150' to the center of town....13" up around 700-800' and 15-16" for ORH airport and Will. Will almost doubled me total at 500' higher...

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We should keep in mind that the GFS low levels tend to bias warm too...but it might be a catch 22 where the sooner the colder air comes in, the drier the low levels get inhibiting precip.

My post to Phil didn't take but this is kind of what I was saying in response...that it'll be interesting to see if the NAM temp profiles and GFS QPF profiles in general work best.

Euro should tell the story.

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The NAM clown map jackpots you with 1.5 new, congrats

yeah the NAM would probably offer up several hours of 34F SN- or something. it cools off the low levels pretty nicely and drops the freezing level much lower much faster. hopefully it's more than just one of those weenie snows when you're staring at your windshield and seeing a few of those fat rain drops with frozen specs showing up.

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This past storm...9" for me (475')....11" up 150' to the center of town....13" up around 700-800' and 15-16" for ORH airport and Will. Will almost doubled me total at 500' higher...

Some of that def had to do with the dryslot too...I didn't get into as much as you did. The elevation def helped...absolutely no doubt...but I think the upslope flow also helped me avoid less dryslotting and the natural synoptics favored areas west and northwest anyway. I remember seeing that dryslot come in before I lost power...and you were around 10dbz and we were still rotting at 20dbz or so on the eastern edge of the ORH hills spine.

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We should keep in mind that the GFS low levels tend to bias warm too...but it might be a catch 22 where the sooner the colder air comes in, the drier the low levels get inhibiting precip.

yeah that's true - though the difference is pretty staggering at like 21z and especially 00z. gfs temps at around 2K feet are still at or above freezing through dinnertime...while the NAM has the 925 0C isotherm blowing past the benchmark at 00z. :lol:

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yeah the NAM would probably offer up several hours of 34F SN- or something. it cools off the low levels pretty nicely and drops the freezing level much lower much faster. hopefully it's more than just one of those weenie snows when you're staring at your windshield and seeing a few of those fat rain drops with frozen specs showing up.

That's what I expect, if it extends to night time maybe real flakes for a while but IMHO, meh

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yeah that's true - though the difference is pretty staggering at like 21z and especially 00z. gfs temps at around 2K feet are still at or above freezing through dinnertime...while the NAM has the 925 0C isotherm blowing past the benchmark at 00z. :lol:

Would these be your first flakes if you saw them?

I can't remember if you ended as some flakes on 10/30.

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How does warmer or cooler SSTA's in the northern Pacific around the Gulf of Alaska region correlated to the EPO if at all?

The EPO covers a region that is kind of on the line between a -EPO and a +EPO in terms of those SST reflections...but a -PDO (cold GOA and warm south of the Aleutians) generally favors a +EPO and an Alaska vortex...esp the SE side of AK and a -PNA. But it favors an Aleutian ridge and that pokes up into the Bearing Straight so the EPO can be negative there. There is not a good correlation to the actual EPO number since it rides the line.

The biggest difference you see is south of the Aleutians.

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The EPO covers a region that is kind of on the line between a -EPO and a +EPO in terms of those SST reflections...but a -PDO (cold GOA and warm south of the Aleutians) generally favors a +EPO and an Alaska vortex...esp the SE side of AK and a -PNA. But it favors an Aleutian ridge and that pokes up into the Bearing Straight so the EPO can be negative there. There is not a good correlation to the actual EPO number since it rides the line.

The biggest difference you see is south of the Aleutians.

Thanks.

I asked b/c I'm kind of worried about the EPO going through the winter. I still believe we will see the NAO tank as we go through winter and possibly be quite negative at times given the SSTA configuration around Greenland, however, the question here becomes do we get any help from the EPO/PNA?

The EPO has been predominately positive since early spring and there really don't appear to be any signs of it changing phases anytime soon.

The one thing I think we will see from all this during the winter and as we get towards late month is a much stormier and active weather pattern...not that we need a great deal of cold air here hopefully we just don't get storms that are cutting to the west of us.

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Many would pick the NAO if we could have one index on our side, but I would favor the EPO.....there is just not much you can do if the "source" region is not much of a source at all.

New England temps are correlated more to the EPO anyway than the NAO...the NAO is still a strong correlation, but not as big as further south.

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Many would pick the NAO if we could have one index on our side, but I would favor the EPO.....there is just not much you can do if the "source" region is not much of a source at all.

Works to an extent. We're past that point with the current state of the Pacific. Even if we had a moderately favorable NAO (which we may be dealing with in 2-3 weeks), we need the black hole vortex over Alaska to get gone. In New England especially, and even without this vortex, the EPO has a very strong correlation...moreso than 40 S.

Look at how dominant that one feature is over the whole pattern, even on a global scale. http://www.meteo.psu.edu/~gadomski/ENSHGTAVGNH_18z/f192.gif

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New England temps are correlated more to the EPO anyway than the NAO...the NAO is still a strong correlation, but not as big as further south.

Yup.

I think the greatest influence the NAO has is holding cold in once it is present and slowing storm systems.....it kind of forces them to take a decent track.

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Many would pick the NAO if we could have one index on our side, but I would favor the EPO.....there is just not much you can do if the "source" region is not much of a source at all.

Agreed.

Take a look at DEC of 1952 for example. NAO was fairly negative, however, the EPO was quite positive.

cd71.235.37.152.319.22.30.36.prcp.png

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Yup.

I think the greatest influence the NAO has is holding cold in once it is resent and slowing storm systems.....it kind of forces them to take a decent track.

Yes...the NAO is important as we average more snow easily in -NAO winters than +NAO but our lefty/righty splits are def a lot less than the Mid-Atlantic.

We kind of live on the gradient of Canada and the M.A....so not one index can control our fate as much as further south. Its why we can succeed in winters like '07-'08, '93-'94 (big time...even NYC got in on that winter), '81-'82, '75-'76, '71-'72, and '56-'57 while further south has really struggled in those type of winters.

We often get screwed too, but its those 1 out 3 or 4 winters where we still clean up that makes our climo.

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