Feb 8th-9th Potential Significant Coastal Storm

[ctsnowstorm628]

with the low bombing to the east, wouldn't really matter-the freezing line would crash S and E

I'm aware...just stating what it shows lol

[SR Airglow]

Upton onboard for decent totals in southern CT, a foot+ for me, even 6-8" in the city. Would be shocked if all of CT is not under a watch in the next hour or so. Suprised at this map, they usually are conservative, but guess the GFS coming around was enough for them.

 

-skisheep

[USCAPEWEATHERAF]

I agree Scot, NAM can be tossed this cycle, off run.  Also I believe the rest of SE MA and RI will see Blizzard Watches up, especially Plymouth and Barnstable counties.

[SnowGoose69]

The NAM has been doing this for years now, it finally grasps an idea on a 00 or 12Z  run and then loses it on the ensuing 06 or 18...it totally lost the 12/19/09 event on a 06z run after it finally picked it up on the 00z being one of the last models to do so, it will be back to or better than its 12Z solution tonight for sure

[dryslot]

Jaw Drop...............

 

[CT Rain]

18z NAM is late with the phase, along with a weaker southern stream ... does display how sensitive of a forecast scenario this really is

 

While it is the NAM the solution of a later phase with more taint here in CT is certainly on the table. 

[SnowMan]

Jaw Drop...............

 

d13_fill.gif

I have to think with the ratio and more than 2" of QPF we are seeing 24+

[Zeus]

And why, exactly, are we tossing out the 18z NAM?

[dryslot]

I have to think with the ratio and more than 2" of QPF we are seeing 24+

 

 

I have a high at the height of the storm forcasted for here@ 12F

[CT Rain]

While it is the NAM the solution of a later phase with more taint here in CT is certainly on the table. 

 

With that in mind, the area farther east (i.e. Boston) have much more wiggle room here. So before Kevin locks in 30" for his backyard let's remember how rare 18" of snow is for him (it's happened like twice) and be mindful of some of the issues.

 

I'd definitely be chucking in Boston and 128 corridor right now. 

[dryslot]

lol, 15z SREF mean here 37.96", 1 weenie member 71.26", 3 in the 50" range

[Clinch Leatherwood]

18z NAM is late with the phase, along with a weaker southern stream ... does display how sensitive of a forecast scenario this really is

 

Yes, it shows what a few hours too late does to the phase.  People need to remember the Euro did bump east early on compared to earlier runs but managed to capture the system at the last minute.  It's a VERY fine line.  As bad as the NAM is in this years progressive pattern it gives a little pause prior to the rest of the 18z suite.  JMHO

While it is the NAM the solution of a later phase with more taint here in CT is certainly on the table.

Exactly, it's not like the idea of a later phase is foreign. Been talked about as one of the red flags.

[Damage In Tolland]

With that in mind, the area farther east (i.e. Boston) have much more wiggle room here. So before Kevin locks in 30" for his backyard let's remember how rare 18" of snow is for him (it's happened like twice) and be mindful of some of the issues.

I'd definitely be chucking in Boston and 128 corridor right now.

Of course . Any way for me to not get good snows you'll find it. ESP when it looks like valley is too far west

[SnowGoose69]

Yes, it shows what a few hours too late does to the phase.  People need to remember the Euro did bump east early on compared to earlier runs but managed to capture the system at the last minute.  It's a VERY fine line.  As bad as the NAM is in this years progressive pattern it gives a little pause prior to the rest of the 18z suite.  JMHO

The NAM is always slow with stuff, always, even at 12 hours it brings in precip shields too slow and beyond 36 its worse, this may be why the NAM has major issues beyond 48 and sometimes even inside of that with systems the last few years

[CT Rain]

 

Yes, it shows what a few hours too late does to the phase.  People need to remember the Euro did bump east early on compared to earlier runs but managed to capture the system at the last minute.  It's a VERY fine line.  As bad as the NAM is in this years progressive pattern it gives a little pause prior to the rest of the 18z suite.  JMHO

Exactly, it's not like the idea of a later phase is foreign. Been talked about as one of the red flags.

 

Yeah I certainly am not relying on the NAM for anything. It's a piece of garbage. But I certainly can envision a scenario where a later phase leads to an 8-12 kind of scenario here and not a 12+. I feel much more confident in 12+ up in eastern Mass.

[OSUmetstud]

And why, exactly, are we tossing out the 18z NAM?

same reason that no one should be thinking of the 50" that the 12z had for Boston? 

 

It's a bad model at that range...considerably worse than the globals.  It's skill only gets to the GFS/Euro at about 24 hours.

[wxmanmitch]

Very cool image... do you know what you found these products?

 

I plotted it myself using a GrADS script that I wrote a while back. Basically the plot calculates and plots the depth of the layer where temperatures are between -12° C and -18° C, RH >= 75%, and omega <= -0.5. It also assumes that the precipitation reaches the ground as snow.

[CoastalWx]

The 12z euro ensembles may actually have been a hair west of the op. someone can check.

[Typhoon Tip]

The NAM has been doing this for years now, it finally grasps an idea on a 00 or 12Z  run and then loses it on the ensuing 06 or 18...it totally lost the 12/19/09 event on a 06z run after it finally picked it up on the 00z being one of the last models to do so, it will be back to or better than its 12Z solution tonight for sure

 

 

What's funny is that even with this weaker impact, your' still talking close to foot of snow from this run - 

[HIPPYVALLEY]

And why, exactly, are we tossing out the 18z NAM?

I'll be riding the caution bus with you and few other weenies until tomorrow morning. I've seen too many winters to go big just yet.

[CoastalWx]

I plotted it myself using a GrADS script that I wrote a while back. Basically the plot calculates and plots the depth of the layer where temperatures are between -12° C and -18° C, RH >= 75%, and omega <= -0.5. It also assumes that the precipitation reaches the ground as snow.

Strong work.

[OSUmetstud]

the 12z euro did have a slightly latter phase.  You can ask Forky...the 00z was great for him but the 12z was meh.

[mahk_webstah]

I have a high at the height of the storm forcasted for here@ 12F

I don't want to jinx anything....but the Euro has me at almost 2" qpf.  Some of that is going to be 15+-1.  You do the math.

[CT Rain]

The 12z euro ensembles may actually have been a hair west of the op. someone can check.

 

A tick west it appears. Good news there. 

[ORH_wxman]

 

The 12z euro ensembles may actually have been a hair west of the op. someone can check.

 

They were pretty amped...they destroy you though, lol.

[Sn0waddict]

Well Mount Holly WFO just put in central NJ so a watch for Long Island, NYC and CT looks all but inevitable now.

Should be any minute now considering the forecast map they just made

 

 

 

http://www.erh.noaa.gov/okx/stormtotalprecip.php

[OSUmetstud]

at least toronto blizzard will be taking down the rope from the rafters.

[Damage In Tolland]

A tick west it appears. Good news there.

When will you lower amounts to 3-6 statewide?

[Zeus]

same reason that no one should be thinking of the 50" that the 12z had for Boston? 

 

It's a bad model at that range...considerably worse than the globals.  It's skill only gets to the GFS/Euro at about 24 hours.

 

Okay, but the later, further east scenario isn't entirely unreasonable.

[phil882]

18z NAM is late with the phase, along with a weaker southern stream ... does display how sensitive of a forecast scenario this really is

 

You can see the similarities between the NAM and the NMM members of the SREF guidance. This is because they share the same dynamical core (although dtk can correct me if I am wrong). At this point, this also seems to be on the less intense or delayed phasing side of the coin, which means the coastal low does not develop quite as fast or as far west.