Snow, or no Snow?

You guys know the drill!! Questions, comments, concerns, please leave them here and I'll do my best!!

To our fearless leader and fellow moderators; should we just put any further discussion of this system in this thread??

Enjoy!!!

https://drive.google.com/open?id=0Byod2Sk27yNYemNyNDZWNVEyWGc

Thanks Ray. Will watch when I get home from work. Yes we can use this thread for discussion purposes too.

Ray didn't get a chance to listen to the video yet however today's rgem cold and snowy 4 parts of our area especially where you are ray. At 8 a.m. Thursday morning freezing line just north of the city 850's still below zero New York City on Northward. Nam is too warm rain for most of the area but it's usually to far North with systems this far out in time.

It's going to depend mostly on when precipitation arrives. The atmosphere is dry however over-running precip usually comes in quickly and ahead of what model show. Probably anything before 10 a.m. will be some form of Frozen precip north and west of I-287

I saw the Rgem, Al, but it's not just the 850s that matter. The 925s are also warm, and warm before the 850s. However, even looking at the 850s, the freezing line basically follows the advancement of the precipitation shield, because that is where the best forcing for the precipitation is coming from - the strong low level warm advection. So they are essentially going occur simultaneously. The precip may start as snow but will very quickly go right to rain, even for the elevated areas in our board. At least in my opinion.

Trend today is precip arriving later in the day Thursday, as well as, warmer boundary layer temperatures. The GFS has warm 925's for almost everyone and this is the "coldest" frame of the model run.


850mb




925mb

With time of year, HP placement, and still exceptionally warm air to our south that warm nose at 925 and 850 is going to win out. I hope my peeps in the HV see a few flakes, but I just don't see it happening esp if precip starts late.

Rayno saying  wet bulb temps at 32 or jus lower in his video from thus afternoon saying poc, Catskill mtn tops may see several inches. WAA events udually are quicker with moisture. It's early climo not on our side in this region by Hi res models saying we start as snow and then quickly changel er NNJ and LHV 287 North. We'll see but white gold baby.

amugs wrote:

yea mugs all6z guidance has trended colder. lets see what today's models show.

not a lot of snow but many n/w suburbs should see their first flakes

uptons disco...

The forcing initially Thursday will be the warm air advection
aloft evident with the isentropic lift. However, the model
soundings are not showing much of a warm nose around 5kft above
the surface. The temperatures gets to near or just above freezing
near 5kft, with surface temperatures right near to just below
freezing Thursday morning. This portends to more of a snow and
sleet scenario without complete melting of falling ice crystals as
there will be a greater area below freezing within the boundary
layer.

Snow accumulations across parts of the interior including portions
of Northeast NJ, the Lower Hudson Valley and SW Connecticut could
reach 1 to possibly 2 inches of snow. The soundings are actually
showing sufficient icing with moist vertical profiles in between
the -10 to -30 degree C levels. This is portraying the moisture
coming in first tonight as mid and high levels clouds tonight and
then gradually lowering and thickening towards early Thursday with
increasing low level moisture thereafter through much of Thursday
night.

sounding for nyc at 12z (8am) thurs....
-------------------------------------------------------------------------------
LEV PRES  HGHT  TEMP  DEWP  RH  DD   WETB DIR SPD THETA THE-V THE-W THE-E   W
    mb     m     C     C    %   C     C  deg knt   K     K     K     K    g/kg
-------------------------------------------------------------------------------
SFC 1020    87   5.2  -0.3  68  5.5   2.8  61   7 276.8 277.4 275.0 286.8  3.66
 1 1000   249   4.0  -2.0  65  6.0   1.6  69  12 277.2 277.8 274.8 286.3  3.31
 2  950   665   1.4  -3.5  70  4.9  -0.5 107  11 278.6 279.2 275.2 287.3  3.10
 3  900  1098  -1.2  -4.6  78  3.4  -2.5 156   8 280.2 280.7 276.0 288.7  3.02
 4  850  1554  -0.0  -3.3  78  3.3  -1.4 225  14 286.1 286.7 279.6 296.2  3.51
 5  800  2040   0.4   0.0  97  0.4   0.3 245  26 291.6 292.5 283.6 305.5  4.80
 6  750  2559   0.2  -0.8  94  0.9  -0.3 255  34 296.8 297.6 285.7 311.0  4.83
 7  700  3110  -2.6  -3.5  94  0.9  -3.0 260  38 299.6 300.4 286.2 312.3  4
if precip is falling att then nyc could wet bulb and snow could fall. sleet would certainly be possible with these soundings. n /w would be colder than this so snow would be likely if precip starts att.

algae888 wrote:uptons disco...

The forcing initially Thursday will be the warm air advection
aloft evident with the isentropic lift. However, the model
soundings are not showing much of a warm nose around 5kft above
the surface. The temperatures gets to near or just above freezing
near 5kft, with surface temperatures right near to just below
freezing Thursday morning. This portends to more of a snow and
sleet scenario without complete melting of falling ice crystals as
there will be a greater area below freezing within the boundary
layer.

Snow accumulations across parts of the interior including portions
of Northeast NJ, the Lower Hudson Valley and SW Connecticut could
reach 1 to possibly 2 inches of snow. The soundings are actually
showing sufficient icing with moist vertical profiles in between
the -10 to -30 degree C levels. This is portraying the moisture
coming in first tonight as mid and high levels clouds tonight and
then gradually lowering and thickening towards early Thursday with
increasing low level moisture thereafter through much of Thursday
night.

I think that's very bullish. I'm standing firm right now with my call of a T-1" at most for regions above 1000' right now. I don't see any evidence for me to change. Will be watching today's runs closely, though haha

ray I believe it all comes down to start time esp for those n/w of nyc. waa usually comes in faster than modeled. while this will mean little difference for nyc metro, areas further n and w could see some accumulations. it's October so climo is against us but many suburbs will be down in the low 20's tonight so cold air is available. great that we are even tracking att.

algae888 wrote:ray I believe it all comes down to start time esp for those n/w of nyc. waa usually comes in faster than modeled. while this will mean little difference for nyc metro, areas further n and w could see some accumulations. it's October so climo is against us but many suburbs will be down in the low 20's tonight so cold air is available. great that we are even tracking att.

I agree with that. The problem that I'm seeing is that this isn't a nice, gradual evolution of the warm advection, where there is a gradual ascent of the air as it rides the warm front through the column. This is a 0-60 type of event, where there is a relatively small area of very intense warm advection, which is where the precipitation will be (since that's the main forcing for it). So, once precipitation starts reaching the ground, that will be the same time that the low-level warm advection is ramping up because the low-level (i.e. 850/925 mb warm front) is very near by. The precipitation should rather quickly ramp up in intensity, but at the same time, the low-levels will be rapidly warming because of the strength of the advection, which is why I can see a brief burst of snow and/or sleet for areas above 1000', but even there it should quickly transition to liquid because the low-level advection is so strong. Now, icing in those areas could be a little bit more of a problem than I first thought, as you mentioned, surface temperatures will be below freezing for a bit. However, based on the expected intensity of the precipitation underneath the advection, I think those chances are still rather small for any significant icing.

I am missing the timing. Around 10 am?

WOOP WOOP UPTON BABY BRING IT!!


SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NEW YORK NY
348 PM EDT WED OCT 26 2016

CTZ005-006-NJZ002-004-103-NYZ067>070-270900-
NORTHERN FAIRFIELD-NORTHERN NEW HAVEN-WESTERN PASSAIC-
EASTERN PASSAIC-WESTERN BERGEN-ORANGE-PUTNAM-ROCKLAND-
NORTHERN WESTCHESTER-
348 PM EDT WED OCT 26 2016

...FIRST WINTRY PRECIPITATION DEVELOPING LATE TONIGHT...

THE FIRST WINTRY PRECIPITATION EVENT OF THE SEASON IS EXPECTED
FROM LATE TONIGHT INTO EARLY THURSDAY MORNING. A LIGHT MIXTURE OF
SNOW AND SLEET IS EXPECTED TO BEGIN AFTER MIDNIGHT ACROSS ORANGE
AND ROCKLAND COUNTIES OF NEW YORK...AND PASSAIC WESTERN BERGEN
COUNTIES OF NEW JERSEY. TOWARD THURSDAY MORNING...DURING THE RUSH
HOUR...THE WINTRY PRECIPITATION BECOMES MORE LIKELY WITH LIGHT
ACCUMULATIONS OF SNOW AND SLEET. THEN EARLY THURSDAY MORNING THE
SNOW AND SLEET IS EXPECTED TO MIX WITH RAIN BEFORE CHANGING OVER
TO ALL RAIN BY NOON.

TOTAL SNOW AND SLEET ACCUMULATIONS ARE EXPECTED TO RANGE FROM A
TRACE TO 1 1/2 INCHES WITH THE HIGHEST AMOUNTS ACROSS EXTREME
WESTERN ORANGE COUNTY.

IF TRAVELING LATE TONIGHT AND EARLY THURSDAY MORNING BE PREPARED
FOR THE FIRST WINTRY WEATHER OF THE SEASON AND EXERCISE CAUTION.

amugs wrote:WOOP WOOP UPTON BABY BRING IT!!


SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NEW YORK NY
348 PM EDT WED OCT 26 2016

CTZ005-006-NJZ002-004-103-NYZ067>070-270900-
NORTHERN FAIRFIELD-NORTHERN NEW HAVEN-WESTERN PASSAIC-
EASTERN PASSAIC-WESTERN BERGEN-ORANGE-PUTNAM-ROCKLAND-
NORTHERN WESTCHESTER-
348 PM EDT WED OCT 26 2016

...FIRST WINTRY PRECIPITATION DEVELOPING LATE TONIGHT...

THE FIRST WINTRY PRECIPITATION EVENT OF THE SEASON IS EXPECTED
FROM LATE TONIGHT INTO EARLY THURSDAY MORNING. A LIGHT MIXTURE OF
SNOW AND SLEET IS EXPECTED TO BEGIN AFTER MIDNIGHT ACROSS ORANGE
AND ROCKLAND COUNTIES OF NEW YORK...AND PASSAIC WESTERN BERGEN
COUNTIES OF NEW JERSEY. TOWARD THURSDAY MORNING...DURING THE RUSH
HOUR...THE WINTRY PRECIPITATION BECOMES MORE LIKELY WITH LIGHT
ACCUMULATIONS OF SNOW AND SLEET. THEN EARLY THURSDAY MORNING THE
SNOW AND SLEET IS EXPECTED TO MIX WITH RAIN BEFORE CHANGING OVER
TO ALL RAIN BY NOON.

TOTAL SNOW AND SLEET ACCUMULATIONS ARE EXPECTED TO RANGE FROM A
TRACE TO 1 1/2 INCHES WITH THE HIGHEST AMOUNTS ACROSS EXTREME
WESTERN ORANGE COUNTY.

IF TRAVELING LATE TONIGHT AND EARLY THURSDAY MORNING BE PREPARED
FOR THE FIRST WINTRY WEATHER OF THE SEASON AND EXERCISE CAUTION.

Ill believe it when I see it. Who on our board can report??

Janet Me, DOC, CP, SNOW in EPA, SNOW247 in Rockland Cty.
This is not NYC Metro but more N & W - HRRR and Hi Res models showing precip coming in faster as would be with WAA. WE shall see but if I see pinger and mangled flakes so be it.

amugs wrote:Janet Me, DOC, CP, SNOW in EPA, SNOW247 in Rockland Cty.
This is not NYC Metro but more N & W - HRRR and Hi Res models showing precip coming in faster as would be with WAA. WE shall see but if I see pinger and mangled flakes so be it.

Like I told ya mugsy, I'll text you and wake you up tonight if I see something frozen!

Will have to see how entrenched the Cold Air here is. Could be messy night tomorrow if CAD is strong in the valley. Temps should be in mid 30s most of day into the night per guidance. I think we may be a little colder and that starts issues.

I'm up here in North-western Passaic County. Right on the NY State border. I will certainly let you all know what happens here! Our school district has already called a delayed opening for tomorrow.

I hope the white gold is flying even if for a short time.

Already down to 36 here. Smells like snow