Re: Monday 12/5 Snow Showers Discussion / Observations

by **Frank_Wx** Sun Dec 04, 2016 7:38 pm

HRRR @ 4:00am tomorrow. You can see where the rain/snow line is.

Monday 12/5 Snow Showers Discussion / Observations - Page 2 Hrrr_ref_nj_11

by Guest Sun Dec 04, 2016 7:42 pm

I can't believe all the "excitement" for an inch or 2 of snow.

Also its 35 degrees here at 7:30. we are expecting rain after midnight??????????? Usually the column and temperature goes down at night, especially as we wet bulb no???

by **Frank_Wx** Sun Dec 04, 2016 7:44 pm

The 925mb isotherm nicely follows where the r/s line is. This isotherm was solidly more S&E a couple of days ago.

by **Frank_Wx** Sun Dec 04, 2016 7:46 pm

syosnow94 wrote:I can't believe all the "excitement" for an inch or 2 of snow.

Also its 35 degrees here at 7:30. we are expecting rain after midnight??????????? Usually the column and temperature goes down at night, especially as we wet bulb no???

Winds are from the NE shifting from the south. Normally our snow events have a west-northwest wind.

by **Math23x7** Sun Dec 04, 2016 7:50 pm

syosnow94 wrote:I can't believe all the "excitement" for an inch or 2 of snow.

Also its 35 degrees here at 7:30. we are expecting rain after midnight??????????? Usually the column and temperature goes down at night, especially as we wet bulb no???

Looking at guidance, the is no low pressure off the coast; the low is in the great lakes region passing us to our north. Also, there is no big high pressure to our north and west; there are high pressures in the South and to our east. Throw in the fact the the water temperatures are around 50 degrees near the coast. All of this means rain for the I-95 corridor.

by **Frank_Wx** Sun Dec 04, 2016 7:56 pm

Math23x7 wrote:
syosnow94 wrote:I can't believe all the "excitement" for an inch or 2 of snow.

Also its 35 degrees here at 7:30. we are expecting rain after midnight??????????? Usually the column and temperature goes down at night, especially as we wet bulb no???

Looking at guidance, the is no low pressure off the coast; the low is in the great lakes region passing us to our north. Also, there is no big high pressure to our north and west; there are high pressures in the South and to our east. Throw in the fact the the water temperatures are around 50 degrees near the coast. All of this means rain for the I-95 corridor.

Good post

by **rb924119** Sun Dec 04, 2016 8:11 pm

Here's my final call for this event:

Start: 11pm-2am
End: 9am-12pm

Monday 12/5 Snow Showers Discussion / Observations - Page 2 Slide210

It's basically unchanged from my first call yesterday, but I didn't feel that "1-3", locally higher amounts" was going to adequately cover the range here, mainly in the higher elevations, which is why I have the blue, 2-5" regions. I admit that I think most locations in these areas will be in the 2-3/3.5" range, but I wanted to account for the possibility of another over performance and lollipop amounts in excess of 4". I know this seems very high, but I had a post that detailed my thoughts about this event. Since that post (if you want me to find it, just let me know and I'll post the link), the forcing mechanisms that I outlined actually have trended a bit stronger in my opinion; mainly with respect to the lower-level warm advection/isentropic/upglide forcings. I also noticed that instead of having a split-flow of advection, where this system would have air originating around the Tennessee Valley, there is now broad agreement that there will be a fetch with origins in the northern Gulf. Although I don't believe that air will entirely make it this far north in time, the fact that there is more of a southerly fetch ahead of this system as it arrives into our region versus what was earlier progged to be more southwesterly, leads me to believe that another over performance is at the very least plausible.

In addition, I also believe that the regions in blue will see dendrites and hexagonal plates as snowflake structures based on the thermal profiles, and with lower-level profiles between 0 and -5°C through the precipitation-formation layer, there is strong support for aggregate snowflakes (what I call chicken feathers). Because of this, I think the snow will stack up quick once it starts falling, especially since many of these regions are already below freezing, so snow will not be lost to melting. I think snowfall rates could reach or eclipse 1"/hr at times in these regions, which also supports my map. Secondly, this is also a test for me. I am playing a hunch by going higher here, a hunch that I had last time but never pulled the trigger on. I'm taking the shot this time, and if no lollipop amounts verify, oh well, because I still strongly believe that the low of end of that range is going to verify in those regions, with my other regions also still on track. We'll see. Discuss!!

by **Frank_Wx** Sun Dec 04, 2016 8:15 pm

Ray - 700mb frontogenesis seems decent over your blue shaded areas, but not much vertical velocity to work with. Also, the jet streak seems unfavorably positioned.

Monday 12/5 Snow Showers Discussion / Observations - Page 2 Gfs_uv250_eus_3

Monday 12/5 Snow Showers Discussion / Observations - Page 2 Gfs_uv250_eus_3

by **rb924119** Sun Dec 04, 2016 8:21 pm

Frank_Wx wrote:Ray - 700mb frontogenesis seems decent over your blue shaded areas, but not much vertical velocity to work with. Also, the jet streak seems unfavorably positioned.

I know; these are points that were brought up the other day. My argument is that because you are working with a long fetch of warm advection, the vertical velocities at any one layer WILL NOT be impressive, but you don't need them to be because you are forcing the air to rise regardless; just over a longer distance. Strong vertical velocities are usually associated with forcings that are very concentrated. In this case, the forcings are much more spread out, but still working constructively. Don't forget, even if the air we get originates in Virginia, it still has a higher water content than our air, so you don't need as much vertical velocity to force condensation and precipitation formation. But the jet streak, you're absolutely right; all of the forcing is sub-300hPa. I just think the other levels will compensate.

by **Frank_Wx** Sun Dec 04, 2016 8:28 pm

I see. Thanks!

by **rb924119** Sun Dec 04, 2016 8:36 pm

We're gonna find out, Frank haha that's for sure lmao I'm testing a few different hypotheses with this. Last time I didn't pull the trigger when I wanted to because I didn't feel confident enough in going significantly higher than most guidance was showing. This time, I don't want any regrets (even though if it doesn't work I'll regret not following guidance) ahaha It's always a no-win white flag

by **Frank_Wx** Sun Dec 04, 2016 8:37 pm

Hey, it's a minor event. Whatever happens I would not get too high or down on it. The only impact this storm will have is the timing is morning rush hour. JOY!

Precip looks a little ragged.

by **rb924119** Sun Dec 04, 2016 8:41 pm

Frank_Wx wrote:Hey, it's a minor event. Whatever happens I would not get too high or down on it. The only impact this storm will have is the timing is morning rush hour. JOY!

Precip looks a little ragged.

It does, but I think it looks a little healthier in between the two fetches than it did a few hours ago. I think it will start looking better as we get deeper into the night. I HOPE it does Rolling Eyes

But you're definitely right; I'm doing my best and that's all I can ask. Strive for perfection, expect nothing but errors. And yeah, the morning commute is gonna be sloppy lol

by **Frank_Wx** Sun Dec 04, 2016 8:52 pm

It's snowing in Ohio

Monday 12/5 Snow Showers Discussion / Observations - Page 2 Cy4CmLcWIAA4NMa

by **rb924119** Sun Dec 04, 2016 8:59 pm

Where is that?? It's gorgeous wherever it is aha

by **hyde345** Sun Dec 04, 2016 9:36 pm

syosnow94 wrote:I can't believe all the "excitement" for an inch or 2 of snow.

Also its 35 degrees here at 7:30. we are expecting rain after midnight??????????? Usually the column and temperature goes down at night, especially as we wet bulb no???

Because when you live in the Hudson Valley and your snowfall total last year was 6 inches and most of that fell in April any snow is a big deal.

by **Frank_Wx** Sun Dec 04, 2016 9:40 pm

hyde345 wrote:
syosnow94 wrote:I can't believe all the "excitement" for an inch or 2 of snow.

Also its 35 degrees here at 7:30. we are expecting rain after midnight??????????? Usually the column and temperature goes down at night, especially as we wet bulb no???

Because when you live in the Hudson Valley and your snowfall total last year was 6 inches and most of that fell in April any snow is a big deal.

by **amugs** Sun Dec 04, 2016 10:08 pm

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
922 PM EST SUN DEC 4 2016

NJZ001-007>009-PAZ054-055-060>062-105-050900-
SUSSEX-WARREN-MORRIS-HUNTERDON-CARBON-MONROE-BERKS-LEHIGH-
NORTHAMPTON-UPPER BUCKS-
INCLUDING THE CITIES OF...NEWTON...WASHINGTON...MORRISTOWN...
FLEMINGTON...JIM THORPE...STROUDSBURG...READING...ALLENTOWN...
BETHLEHEM...EASTON...CHALFONT...PERKASIE
922 PM EST SUN DEC 4 2016

...SNOW EXPECTED OVERNIGHT...

A QUICK MOVING STORM SYSTEM WILL IMPACT THE SOUTHERN POCONOS...NORTHERN
NEW JERSEY AND PARTS OF THE LEHIGH VALLEY OVERNIGHT. SNOW WILL LIKELY
BEGIN AROUND MIDNIGHT ACROSS BERKS COUNTY PENNSYLVANIA AND THEN IT
WILL SPREAD NORTH AND EAST ACROSS THE REST OF THE REGION. TWO TO THREE
INCHES OF SNOW MAY OCCUR ACROSS THE HIGHER ELEVATIONS OF THE SOUTHERN
POCONOS WITH ONE TO TWO INCHES EXPECTED ACROSS THE REST OF THE SURROUNDING
COUNTIES.

ANY SNOW MAY CREATE SLIPPERY TRAVEL OVERNIGHT AND IT COULD IMPACT
THE MORNING COMMUTE. MUCH OF THE SNOW WILL TAPER OFF AROUND SUNRISE.
BE PREPARED FOR SOME SLOWER TRAVEL TIMES MONDAY AND DRIVE WITH CAUTION
ACROSS THESE AREAS.

$$

Ray shazaaammmmm!!

by **aiannone** Sun Dec 04, 2016 10:10 pm

29 degrees and cloudy here in Binghamton. Waiting on the first flakes. Should be here within the next hour or so.

by **rb924119** Sun Dec 04, 2016 10:22 pm

amugs wrote:SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
922 PM EST SUN DEC 4 2016

NJZ001-007>009-PAZ054-055-060>062-105-050900-
SUSSEX-WARREN-MORRIS-HUNTERDON-CARBON-MONROE-BERKS-LEHIGH-
NORTHAMPTON-UPPER BUCKS-
INCLUDING THE CITIES OF...NEWTON...WASHINGTON...MORRISTOWN...
FLEMINGTON...JIM THORPE...STROUDSBURG...READING...ALLENTOWN...
BETHLEHEM...EASTON...CHALFONT...PERKASIE
922 PM EST SUN DEC 4 2016

...SNOW EXPECTED OVERNIGHT...

A QUICK MOVING STORM SYSTEM WILL IMPACT THE SOUTHERN POCONOS...NORTHERN
NEW JERSEY AND PARTS OF THE LEHIGH VALLEY OVERNIGHT. SNOW WILL LIKELY
BEGIN AROUND MIDNIGHT ACROSS BERKS COUNTY PENNSYLVANIA AND THEN IT
WILL SPREAD NORTH AND EAST ACROSS THE REST OF THE REGION. TWO TO THREE
INCHES OF SNOW MAY OCCUR ACROSS THE HIGHER ELEVATIONS OF THE SOUTHERN
POCONOS WITH ONE TO TWO INCHES EXPECTED ACROSS THE REST OF THE SURROUNDING
COUNTIES.

ANY SNOW MAY CREATE SLIPPERY TRAVEL OVERNIGHT AND IT COULD IMPACT
THE MORNING COMMUTE. MUCH OF THE SNOW WILL TAPER OFF AROUND SUNRISE.
BE PREPARED FOR SOME SLOWER TRAVEL TIMES MONDAY AND DRIVE WITH CAUTION
ACROSS THESE AREAS.

$$

Ray shazaaammmmm!!

Well at least I'm not alone ahaha thanks Mugs!! My level of anxiety is mildly reduced because of that ahaha like I said to Frank, I'm a bit nervous with this one lmao

by **snow247** Sun Dec 04, 2016 11:04 pm

33f here

by **CPcantmeasuresnow** Sun Dec 04, 2016 11:19 pm

Frank_Wx wrote:I'll take this over last December

30.2 and waiting on the snow. 1-2 expected.

by **1190ftalt** Mon Dec 05, 2016 3:58 am

Just got up in beautiful Stillwater NJ, at 1190 ft alt we have 1 inch of snow, 29 degrees grass and driveway covered, white magic falling from the sky in a nice steady stream!

by **NjWeatherGuy** Mon Dec 05, 2016 4:26 am

Seems like the NAM did better than the GFS again, GFS too warm. Snowing again here, very wet-like, but snow, not a mix, rain on radar. 35 deg.

by **snow247** Mon Dec 05, 2016 4:41 am

Moderate snow here, looks like almost an inch otg. Some roads getting covered.

by **rb924119** Mon Dec 05, 2016 4:54 am

Have somewhere around 2" here with light snow still falling. Hopefully I can get another half inch just to seal the deal haha as I feared, my original forecast was better this time and should have stuck with it (told you Frank!!), because even though the precipitation filed did what I thought it was going to, it moved a little faster than I thought. I thought we'd have about three hours of steady snow and we only saw two. Gonna be interesting to see the observations come in once this wraps up!

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