Feb. 11-12 2019 Wintry Mix Event

This forecast is gonna a royal pain in the rear end for example - 10 miles south of me maybe raining and me sleetfest.
That HP has trended from a 1032 to a 1040ish since Friday and with that the snow range has upped by an inch


This is if the cold air hangs in for about 3-4 more hours and we snow instead of sleet by precip maps

billg315 wrote:So TWC has me 4-8” Tuesday. Accuweather has me 2-4” but increased the % chance of 4-8”. I still think these may be bullish but we are inside of 36 hours and they aren’t backing off. I would also note yesterday my forecast high today was 40*. I briefly hit 34* and just dropped to 33* with thickening clouds so I think I’ll be 5-6* colder today than forecast. Foreshadowing the strength of the cold?? Hmm.

I think for significant snow to occur, this needs to thump at the onset and we get a favorable wind direction for as long as possible. I wouldn't bet on this one way or the other, but the antecedent air mass is good and the high most likely will be anchored for a long time in a decent location. Nowcast at its finest here.

Hard to know who and what to believe anymore this winter. Our board experts have even had trouble predicting storms this season due to last minute complications. However, that is mother nature and anything can happen. Models have been all over the place so whether not we get snow, sleet, freezing rain or all three for this upcoming storm, we at least have something to track.

Forecasts for my area in central NJ, went from less than an inch monday night and 1-3 Tuesday. To 1-3 Monday night and 3-5 Tuesday before going to rain.

Interesting...

The rainfall prediction also went from about an inch to maybe a half inch. Seems to be staying cold longer.

The rainfall prediction also went from about an inch to maybe a half inch. Seems to be staying cold longer.

Irish wrote:Forecasts for my area in central NJ, went from less than an inch monday night and 1-3 Tuesday. To 1-3 Monday night and 3-5 Tuesday before going to rain.

Interesting...

That seems to be the trend today. While I guess the Euro differs the GFS and NAM both have snow starting as far north as the immediate NYC area as early as 1 am and no change to all rain until after 4 pm. That is a long period of frozen precip. This isn’t the same as the mid Jan.storm where it snowed for an hour or two then was pouring rain for the next 12 hours.

algae888 wrote:

billg315 wrote:SENJ, I attribute the quiet board to three things:
1. Frank and Scott have not said much which some people may mistake as this not being a threat - not aware Frank is overseas and not tracking and Scott is busy this weekend;
2. This event has been under-hyped because the initial totals looked low wit a change to rain. Modeling is since trending to a colder solution with more frozen than wet precip, but mainstream outlets are just catching up to that;
3. This winter has been so awful everyone is gun-shy about getting excited for anything - especially a storm as complex as this which has a good upside, but also high bust potential.

I think the main reason most people aren't posting today is because more than half of total precipitation will fall as rain for the majority of the area. There is a warm nose both at 925 Mb and 700 Mb. The one thing that's very concerning is the slow onset of precipitation as shown on most guidance the last few days. Nws is very clear on what can bust this forecast either way and that was one of them. Euro doesn't start precipitation for New York City proper until 8 a.m. Tuesday with warm nose is already pushing it. I'm calling for a few hours of snow and sleet and then mainly rain along the coast obviously freezing rain the further Inland you go just not a good setup we needed that primary to be much much weaker and try and come under us. Doesn't look like that's happening we shall see

Good points. That is going to make or break this forecast. NWS Albany siding with nam on this one because they feel it handles warm noses aloft better in this situation. Still gives me 4-5 inches of snow before changeover to sleet and ZR. I'm really hoping we don't get significant icing.

Dunnzoo wrote:Definitely gun-shy on this one. Mugsy and I are always in the battle zone, what we get, when we get it. We are just far enough outside NYC to be colder sometimes and just close enough to be warmer... ugh. I'm waiting to see what happens overnight and tomorrow morning before getting hyped about any snow. Right now I'm expecting about 4" of snow Tuesday morning before a change to sleet for the afternoon. We'll see.

Zoo with you sista - gonna be a battle as always here - 5-10 miles west will battle but better for them wintry precip wise.
Lets see how this HP trends in the next 24 hours - that will tell us if the cold air can hang - this is dense arctic air again so time will tell.
Hope it starts at midinightish - 1Am time frame and not the Euro.

These set up folks are very tricky for all in this field.

Lets see what the happy hour models have to say and then again the grave yard shift ones and earl morning risers!

No major changes on 18z NAM. Still shows a prolonged sleet storm for most with a few hours of snow at the outset and ending with rain in the evening.

NAM definitely favors cold air staying entrenched. But anxious to see 18z GFS because the NAM also overdid the cold in the mid-Jan storm while GFS was more in line with the quick warmup. Like to see the NAM continue to have backing on that from other models.

Latest forecast discussion from NWS Mt Holly:

Synoptically...The period starts with a warm front well to our south and high pressure centered well to our north. The front will be attached to a low west of the Mississippi. This low will track northeast and be positioned near the Great Lakes 24 hours later, on Tuesday evening. At this time, a secondary low will develop near the coast of NJ and track northeast Tuesday night.

Impacts...This event will cross the Tuesday morning commute as well as the Tuesday evening commute. For the I95 corridor, the morning commute will experience the most impacts. Further north and west, the morning commute will be a snowy one and the evening one could be a mixed bag of snow, ice and freezing rain.

Headlines...Winter Storm Watch posted for the southern Poconos and NW NJ to account for both the snow and ice.

Snow/sleet amounts...Ranging from 5 to 8 across the Southern Poconos and NW NJ, 3 to 5 across Berks and the Lehigh Valley, then 2 to 4 down to I95. 1 to 2 when you cross the river into NJ and also for northern Delmarva. An inch or less south and east of there.

Freezing rain...Tricky here at this point and depends on the
strength of the low-level warm nose. For now, have .2/tenths of ice across the Southern Poconos and NW NJ, .1 to .2/tenths
across Berks, the Lehigh Valley and Morris County in NJ, a trace to a .1/tenth down to the urban I95 corridor, and then a trace south of there. Cape May county and Sussex county may not see much snow or ice at all.

For the Poconos and NW NJ, it`s not out of the realm of
possibility of receiving more ice. Some of the forecast
soundings over the last two runs have up to .4/tenths.

Rain...Not sure the Poconos will ever go over to all rain. The
Lehigh Valley and Berks are forecast to change over late Tuesday, and the urban corridor around midday Tuesday.

QPF...This is not a weak/dry system. Total QPF, when all said
and done will be between 1.00 and 2.00 inches. Where the ptype is mainly liquid, expect minor flooding in the most prone areas. Even across locals that get accumulating snow, moderate to heavy rain is possible after the changeover.

Transitions...As stated, the frozen/freezing may never change over across the far north. For the Lehigh Valley, going with all snow Monday night into Tuesday morning and transitioning to all rain Tuesday afternoon. Across the urban and I95 region, going with snow Monday night to a mix by daybreak Tuesday, followed by all rain in the afternoon. The Tuesday morning commute looks nasty for this area. Across the coastal plain and our southern Delmarva zones, going with snow to rain on Monday night. Looks like all rain here Tuesday and Tuesday night.

Not much change in 18z GFS. Snow reaches immediate NYC area by 1am, stays all snow north of I-195 until mid-morning when it mixes with sleet in parts of central/north NJ (while staying snow n&w of NYC); goes to all rain NYC and south after 3 or 4 pm and to all rain n&w of NYC by 7pm.

Again the key for snow totals is how heavy is the precip when it’s falling as snow and how long does it fall as snow? On the GFS the snow starts pretty early (before midnight in my area, by 1 am around NYC). Other models have it not starting until daybreak. NAM is in between. How long it lasts will be a nowcast. Nobody can say that for sure now. At this point I think the NWS discussion above seems right on snow/sleet accumulation. 2-4” in I-95 corridor with 3-5” N&W of there before changing to rain late in the day. But it has high bust potential. Because if it starts late, and gets overwhelmed by warm air earlier, we’d get didly squat.

WAA always start earlier than models forecast - this is a given peeps, not staying it will start at 10 pm but I am thinking around 1-2AM at this time - we'll know more tomorrow.

Look at this CAD Signature from the 1040 HP on the 18 Z NAM


Look at this push - even by 20 mile ticks


SLEET galore for NNJ into LHV North of I80 by this map - it is going to pour sleep by this map



850's warm right


BL temps not so peeps - ice ice baby



Watches going up and advisories as well - Upton slow to the post as usual

NWS holding steady on their snowfall amounts

Given the way this winter has gone, if I get 3-5” of snow followed by a deluge of sleet for a few hours, I’ll call it a victory.

billg315 wrote:Given the way this winter has gone, if I get 3-5” of snow followed by a deluge of sleet for a few hours, I’ll call it a victory.

What are you guys thinking for westchester NY? Al seems to feel nothing, or very little. But alot of you appear to say cou;d snow a decent amount in NYC so that says to me more up here as its inland a bit. I am just curious if mugs do you think my schools special bus company may call it off tuesday? They did last week and not much happened.

And NWS has 4-6 for us Al, why so negative about this? Been pretty consistent about these amounts past few days.

amugs wrote:WAA always start earlier than models forecast - this is a given peeps, not staying it will start at 10 pm but I am thinking around 1-2AM at this time - we'll know more tomorrow.

Look at this CAD Signature from the 1040 HP on the 18 Z NAM


Look at this push - even by 20 mile ticks


SLEET galore for NNJ into LHV North of I80 by this map - it is going to pour sleep by this map



850's warm right


BL temps not so peeps - ice ice baby



Watches going up and advisories as well - Upton slow to the post as usual

NWS holding steady on their snowfall amounts

NWS upton doesnt even have a Hazerdous weather outlook for southern westchester city or costal CT, which makes no sense in comparison to their snow map.