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Watching November 9th to 12th - First Snow?

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Post by amugs Fri Nov 08, 2019 8:34 pm

Frank how can you be punting Nov??
Where is your sbow winter weenie google??
The GEFs and EPS are forecasting a grinding out drive as Al mentioned above. We'll see if it comes to fruition of course.
Tuesday ms storm has very cold backside air that will have many see their first flakes and even some a coating to an inch for tjis season. And NO this doesn't spell doom for winter . Unless your in Isotherms camp which is backed by much extensive research.

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Post by aiannone Fri Nov 08, 2019 9:48 pm

0z NAM is ugly.
Watching November 9th to 12th - First Snow?  - Page 4 05aa1610

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Post by Math23x7 Fri Nov 08, 2019 11:56 pm

aiannone wrote:0z NAM is ugly.
Watching November 9th to 12th - First Snow?  - Page 4 05aa1610

Three hours later, it gives me snow in Albany.  So there's that Wink

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Post by sroc4 Sat Nov 09, 2019 7:52 am

For those who's expectations for this threat are a developed deepening system need not apply, at least I don't think.  Now that we have approached the 72hr mark I am zooming in on some of the details and notice there are some intriguing intricacies that have me thinking an inch of two is not out of the question, even for the coast, although timing and surface temps for the immediate coast will critical.  

There is a ton of disorganized energy involved here as all of the parts reach the area.  The "energy" Im referring too is the vorticity or spin that occurs at the 500mb level or approx 18,000 feet up.  The spinning air at this level leads to low pressure at the surface.  Low pressure at the surface means rising air and rising air leads to precipitation.  The reason your really not seeing a defined strong low pressure show up on the surface maps is because there are small but strong areas of vorticity all over the place rather than one more consolidated area of vorticity.  Each model has a subtle differences in the positioning and timing for all the focal areas of energy.  Its going to be impossible for a model to pin point this, esp this far out.  The majority of the energy you see below will be coming ashore today into tomorrow.  Where and how strong etc will play a role in where there is enhanced lift as the front pushes through.  Also how deep the trough digs has trended a tad more favorable over the past 24hrs.

Watching November 9th to 12th - First Snow?  - Page 4 500_ne10


The temperature gradient here is real ie: baroclinic enhancement as a lifting mechanism and movement of air.  For those who are not sure what I mean here go put your hand near the edges of a drafty door in your house this am.  With the extremely cold air outside, and the hopefully warm and toasty temps inside you will get a rush of air through the drafty door from the cold outside to the warm inside through the tight space.  Applying that same basic principle here we are getting frigid arctic air "plowing" into warm moist air driving it up and over because we know cold air is more dense relative to warm air.  The tighter the gradient between temperature differences the more quickly the air is forced up over shorter distances. The more quickly air rises the more quickly it cools and the more intense the condensation and precip formation.  Here is a silly visual to help those see what Im saying.
Watching November 9th to 12th - First Snow?  - Page 4 Surfac16
Watching November 9th to 12th - First Snow?  - Page 4 Temp_g10

The map above is the surface temps, but I assure you the 925mb and 850mb level in the atmosphere has the same tight gradient.  

So as the front moves through the area because 1: there is alot of vorticity above there could be isolated enhanced areas of LP enhancing rising motion, and 2) the tight temp gradient will enhance lift such that global models may not be able to see the true details of the QPF over a elatively short period of time; especially in isolated areas.  With the majority of the energy still yet to be over land and or in better sampled regions the true details of how this plays out still needs fine tuning.  It may all still be a whole lot of nuttin, but again a sneaky inch or two for some or many isn't out of the question IMHO.

WE TRACK!!!   What a Face  

Watching November 9th to 12th - First Snow?  - Page 4 Euro_s11
Watching November 9th to 12th - First Snow?  - Page 4 Euro_s12

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Post by Snow88 Sat Nov 09, 2019 8:09 am

I think everyone from NYC north will see their 1st flakes
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Post by amugs Sat Nov 09, 2019 9:27 am

WOOP WOOP!!

Watching November 9th to 12th - First Snow?  - Page 4 EI7jh3HXkAA_s1w?format=jpg&name=medium

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Post by amugs Sat Nov 09, 2019 9:33 am

NAM!! Give me some sleet and snow on teh car top adn we can call it a day!!! Just like 2014!!
Watching November 9th to 12th - First Snow?  - Page 4 Nam_2019-11-09-12Z_075_48.778_274.267_37.167_293.2_Rain-Snow_Radar

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Post by amugs Sat Nov 09, 2019 10:11 am

NAM just did a positive trend at the 700mb and 500mb level with the energy more south by about 50 miles and then redevelops a LP off the Cape which brings 2-4/5" for the HV and 1-2" to us but could be more if this trend or slight tick by about 50 miles or so happens. Something to see if the GFS and EURO show as well.

From Billy at NFSWX
Watching November 9th to 12th - First Snow?  - Page 4 EI8HtkeXsAAETYG?format=jpg&name=medium

Watching November 9th to 12th - First Snow?  - Page 4 EI8HtkhX0AcvSjX?format=jpg&name=large

Watching November 9th to 12th - First Snow?  - Page 4 Namconus_ref_frzn_neus_45

Brings snow in on the backside of this low

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Post by amugs Sat Nov 09, 2019 11:11 am

GFS shows a minor snow with flakes and some sleet for the I95 corridor and more as you move N & W.

Watching November 9th to 12th - First Snow?  - Page 4 5dc6e012dd6f5.thumb.png.126543080c7ac2a972cf7e5dfeb027b7

Watching November 9th to 12th - First Snow?  - Page 4 Gfs_ref_frzn_neus_12


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Post by amugs Sat Nov 09, 2019 11:15 am

Gonna be a fun commute for N & W peeps Tuesday morning - first snow of the season peeps drive like nitwits

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Post by rb924119 Sat Nov 09, 2019 2:11 pm

FWIW I continue to stand by my initial thinking, though am moving my target zone for best snow from the initial “I-95 corridor and/or points east” to “I-95 corridor and/or JUST northwest of it (i.e. 95 would be the dividing line between rain/mix and snow)”.

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Post by rb924119 Sat Nov 09, 2019 2:13 pm

The whole idea of a cutter just irks me, both synoptically and meso-scale dynamically. It doesn’t make sense. I think the Euro is having issues with this, and the recent trends of other global suites in addition to the east-outlying SREFS make me think that there may be creedance to my thinking, at as of now.

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Post by aiannone Sat Nov 09, 2019 9:38 pm

0z nam is 1-3" NW of NYC and Coating along the coast

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Post by rb924119 Sat Nov 09, 2019 10:05 pm

That was a pretty big pie in the face. Will give it until 00z tomorrow before folding. I honestly can’t make sense of it, but if nothing else, it’ll be a learning experience.

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Post by heehaw453 Sun Nov 10, 2019 7:27 am

Euro's been very consistent showing a frontal passage and a change to snow for most on this board. Think there is enough moisture and lift to support precip as opposed to it shutting down like it normally does with a frontal passages.

The surface temps will be close to freezing during the changeover, so i don't expect accumulation on the warmer surfaces for most folks on this board.
C-1" on the colder surfaces would be my guess.

Enjoy the November snow!

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Post by sroc4 Sun Nov 10, 2019 7:47 am

heehaw453 wrote:Euro's been very consistent showing a frontal passage and a change to snow for most on this board.  Think there is enough moisture and lift to support precip as opposed to it shutting down like it normally does with a frontal passages.  

The surface temps will be close to freezing during the changeover, so i don't expect accumulation on the warmer surfaces for most folks on this board.
C-1" on the colder surfaces would be my guess.

Enjoy the November snow!

Agreed.  Will have to watch how quickly temps crash as dew points are very rapidly crashing as well making the exact nature of when the temps are close/at or below freezing at the surface for the coastal plain a difficult aspect for models to identify accurately. Dynamic cooling over a short period of time will be diff to predict. I honestly believe that even the coast may accumulate c-1" esp if there is a quick burst of heavy precip which I anticipate.

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WINTER 2012/2013 TOTALS 43.65"WINTER 2017/2018 TOTALS 62.85" WINTER 2022/2023 TOTALS 4.9"      
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Post by weatherwatchermom Sun Nov 10, 2019 8:59 am

sroc4 wrote:
heehaw453 wrote:Euro's been very consistent showing a frontal passage and a change to snow for most on this board.  Think there is enough moisture and lift to support precip as opposed to it shutting down like it normally does with a frontal passages.  

The surface temps will be close to freezing during the changeover, so i don't expect accumulation on the warmer surfaces for most folks on this board.
C-1" on the colder surfaces would be my guess.

Enjoy the November snow!

Agreed.  Will have to watch how quickly temps crash as dew points are very rapidly crashing as well making the exact nature of when the temps are close/at or below freezing at the surface for the coastal plain a difficult aspect for models to identify accurately. Dynamic cooling over a short period of time will be diff to predict.  I honestly believe that even the coast may accumulate c-1" esp if there is a quick burst of heavy precip which I anticipate.

It's November and I will be happy to see any white flakes here on the Coast of NJ...fingers crossed!!
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Post by amugs Sun Nov 10, 2019 10:22 am

Henry M says it best......

https://videos.files.wordpress.com/iFJSGjxV/2019-11-10-08-11-38_dvd.mp4

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Post by jmanley32 Sun Nov 10, 2019 2:56 pm

It would be cool to see some flakes in November, but I am not counting on it, though SR models do hint at the possibility of a quick back end of the front. We will see.
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Post by Frank_Wx Mon Nov 11, 2019 12:49 pm

Most of us will change from rain to a rain/snow mix then eventually burst of just snow.

Watching November 9th to 12th - First Snow?  - Page 4 Namconus_ref_frzn_neus_27

Watching November 9th to 12th - First Snow?  - Page 4 Namconus_ref_frzn_neus_28

Watching November 9th to 12th - First Snow?  - Page 4 Namconus_ref_frzn_neus_29

Little to no accumulation expected.

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Post by aiannone Mon Nov 11, 2019 2:27 pm

NYC DSNY has a snow alert haha

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Post by jmanley32 Mon Nov 11, 2019 4:58 pm

aiannone wrote:NYC DSNY has a snow alert haha
Oh good lord, lol omg a SNOWFLAKE WE NEVER SEEN IT B4
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Post by jmanley32 Mon Nov 11, 2019 5:00 pm

3km nam has no real snow for the area, maybe a flurry with rain but even rain is short lived.
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Post by nutleyblizzard Mon Nov 11, 2019 5:14 pm

jmanley32 wrote:
aiannone wrote:NYC DSNY has a snow alert haha
Oh good lord, lol omg a SNOWFLAKE WE NEVER SEEN IT B4
After last November's rush hour snowstorm disaster, DSNY no longer taking any chances.
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Post by amugs Mon Nov 11, 2019 8:40 pm

jmanley32 wrote:3km nam has no real snow for the area, maybe a flurry with rain but even rain is short lived.

Any snow is good snow JMAN. Not what was once shown by models of course.You want a repeat on Nov 15th last year, that would be great but look what followed. I'll take this like 2014 on 11/9 when we had sleet and rain showers. That started the step down to a great winter.
Some areas in NW NJ will see a good 1" of snow. Dont underestimate these areas they usually outperform in marginal events.
Why is this happening? The transit of Mercury flying by the orbital path of earth as can be seen earlier today. Whenever you get this cold planet making this pass we get a strong cold front. It has been documented for over a century now. This Mercury pass is a transit is bringing the goods, when this happens usually within 24-36 hours the fro t swings through. 2032 is the next transit.
Next Mercury pass is in about 72 days and we can expect another cold front to swing through.

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Post by aiannone Mon Nov 11, 2019 9:10 pm

I’m looking forward to seeing the flakes tmw. Even if it doesn’t stick. I just hope there are some flakes lol

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Post by Math23x7 Mon Nov 11, 2019 10:32 pm

For me in Albany, it looks like an ice/snow mix for the morning commute. This would be my first accumulation of the season.

For you folks in the tri-state area, this front could provide you with your first flakes of the season.

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