Discussion-OBS slippery plowable moderate to high impact snowstorm with many delays near I95 and inland btwn 10AM Sun 1/19-4AM Mon Jan 20. R/S line uncertain near and east of I95 - parts of LI may be limited snowfall of around 1"?

[the_other_guy]

what is upton doing?

 

They’re gonna go right into a winter storm warning? Kind of negates the whole reason for the watch if you hold off on issuing it.

Everything north of the Bronx should’ve been on a winter storm watch since yesterday.

[BoulderWX]

Maybe we hold off on awarding or deriding any model until *after* the storm… unless you already know the outcome, just be patient and we can dissect which models performed best postmortem. 

[psv88]

5 minutes ago, bluewave said:

We track low placement from 5 days out and are not concerned with P-Types that early. The Euro and GFS started out very suppressed well Southeast of the Benchmark. So the CMC can shift  60-100 miles east next few runs and still win on storm track. Snow amounts are always the last thing we are concerned about since model skill beyond a few days has always been very low here. 
 

 

No. Snow amounts are the only thing we care about actually. 

[wxman]

1 minute ago, BoulderWX said:

Maybe we hold off on awarding or deriding any model until *after* the storm… unless you already know the outcome, just be patient and we can dissect which models performed best postmortem. 

Fair enough but a few of us were saying the rgem was on crack being so far west a few days ago yet it sure seems like the western envelope will prevail here.  

[psv88]

Just now, wxman said:

Fair enough but a few of us were saying the rgem was on crack being so far west a few days ago yet it sure seems like the western envelope will prevail here.  

The western envelope had the city getting zero snow and all rain. Is that your call right now?

[CPcantmeasuresnow]

6 minutes ago, the_other_guy said:

what is upton doing?

 

They’re gonna go right into a winter storm warning? Kind of negates the whole reason for the watch if you hold off on issuing it.

Everything north of the Bronx should’ve been on a winter storm watch since yesterday.

Everything north of southern Westchester has been on a winter storm watch since yesterday. If their confident enough in warning criteria, which is at least 6 inches, I'm sure they will issue at 4 PM. 
What would you have liked them to do differently?

[ILoveWinter]

20 minutes ago, wxman said:

It's not only about snow.  On that score you are correct. But in terms of placement the RGEM has been as or perhaps more consistent than the Euro.  But the relatively small southeast ticks have resulted in a likely snowier outcome.  

Yea this is true. Honestly if this was happening in the Fall or in a warmer airmass with no P type forecasting then we would be saying the RGEM was the most consistent. It’s only now where even small ticks east or west can mean rain vs. snow which provides a sense that the model was terrible when in fact the correction was small. 

[HeadInTheClouds]

3 minutes ago, psv88 said:

No. Snow amounts are the only thing we care about actually. 

So the euro was showing 2 or 3 for me yesterday and the cmc about 8. My forecast is for 6-8. 

[psv88]

Just now, HeadInTheClouds said:

So the euro was showing 2 or 3 for me yesterday and the cmc about 8. My forecast is for 6-8. 

The euro was lighter in amounts and the Canadians gave the poconos 2 feet. That’s now off the table. 
 

Canadians had the city and coast getting zero. That changed in one run lol. 
 

 

[wxman]

I hate to criticize the NWS but really need to question what Mt. Holly is doing here.  Not everyone pays close attention to the weather and just scan the forecast...relying on I phone alerts and the like if anything serious in about to happen.  Mt. Holly does not even have headlines for the winter storm starting tomorrow outside of the NW zones.   While most people "probably" heard something about snow tomorrow we are looking at a likely impactful storm on a holiday weekend starting around 24 hours from now.  I get it, there is much uncertainty but at least an advisory is warranted for most of NJ at this time which can then be escalated to a WSW.

[BxEngine]

10 minutes ago, the_other_guy said:

what is upton doing?

 

They’re gonna go right into a winter storm warning? Kind of negates the whole reason for the watch if you hold off on issuing it.

Everything north of the Bronx should’ve been on a winter storm watch since yesterday.

With the exception of southern westchester, they have been. 

[SnoSki14]

2 minutes ago, wxman said:

I hate to criticize the NWS but really need to question what Mt. Holly is doing here.  Not everyone pays close attention to the weather and just scan the forecast...relying on I phone alerts and the like if anything serious in about to happen.  Mt. Holly does not even have headlines for the winter storm starting tomorrow outside of the NW zones.   While most people "probably" heard something about snow tomorrow we are looking at a likely impactful storm on a holiday weekend starting around 24 hours from now.  I get it, there is much uncertainty but at least an advisory is warranted for most of NJ at this time which an then be escalated to a WSW.

Advisories will go up this afternoon given 12z suite. Probably 2-4 or 3-6" for the non watch zones

[bluewave]

16 minutes ago, psv88 said:

No. Snow amounts are the only thing we care about actually. 

But the models are seldom correct with snow amounts beyond a day or two. So it’s not worth it to get overly invested until much closer in. Since that type of IMBY snow longer range forecasting often leads to disappointment. Unless we go back to 2010-2018 when every snowstorm seemed to overperform.

[HeadInTheClouds]

3 minutes ago, psv88 said:

The euro was lighter in amounts and the Canadians gave the poconos 2 feet. That’s now off the table. 
 

Canadians had the city and coast getting zero. That changed in one run lol. 
 

 

OMG. The canadian never showed 2 ft. It showed 11-12 inches 2 days ago and at 12z today it showed about 8. Don't make it seem so drastic. Every model corrects closer to events including your Euro. 

[TJW014]

Will update/adjust my snow map pending the Euro. As of now, doesn't look like I'll be making any changes except maybe broadening the 4 - 7" section and maybe bumping totals a little bit more 

[psv88]

Just now, bluewave said:

But the models are seldom correct with snow amounts beyond a day or two. So it’s not worth it to get overly invested until much closer in. Since that type of IMBY snow longer forecasting often leads to disappointment. Unless we go back to 2010-2018 when every snowstorm seemed to overperform.

Incorrect to the inch? Sure. But it’s wrong to say models cannot generally predict snow amounts “beyond a day or two”

we have known this was a 3-6/4-8” event (for the snowier areas) for 5 days. Nothing has changed. 

QPF output has generally been between 0.25 and 0.50 for most models. We knew there would be cold air to work with. For areas north and west this was a relatively straightforward forecast. Trickier for areas right on the line

[psv88]

4 minutes ago, HeadInTheClouds said:

OMG. The canadian never showed 2 ft. It showed 11-12 inches 2 days ago and at 12z today it showed about 8. Don't make it seem so drastic. Every model corrects closer to events including your Euro. 

It’s weird how you keep ignoring that the Canadian models gave the city zero snow until today. Why is that?

[Nibor]

1 hour ago, BxEngine said:

I’ll sacrifice all of rjays snow if everyone else gets 3+. Im a nice guy.

 

Actual footage of BxEngine sacrificing Rjay. 

[MJO812]

Ukie died

[Nibor]

21 minutes ago, CPcantmeasuresnow said:

Everything north of southern Westchester has been on a winter storm watch since yesterday. If their confident enough in warning criteria, which is at least 6 inches, I'm sure they will issue at 4 PM. 
What would you have liked them to do differently?

Listen pal, I’ll have you know that I have decades of experience from my arm chair. 

[BoulderWX]

2 minutes ago, MJO812 said:

Ukie died

 2-4” area wide at 10:1

[MJO812]

[wxman]

Still quite a spread so close in.

[bluewave]

15 minutes ago, psv88 said:

Incorrect to the inch? Sure. But it’s wrong to say models cannot generally predict snow amounts “beyond a day or two”

we have known this was a 3-6/4-8” event (for the snowier areas) for 5 days. Nothing has changed. 

QPF output has generally been between 0.25 and 0.50 for most models. We knew there would be cold air to work with. For areas north and west this was a relatively straightforward forecast. Trickier for areas right on the line

Again, models have been all over the place with snowfall amounts and the placement of those amounts. You can see why posters west of I-95 would be hesitant to give the Euro high marks based on this original suppression forecast and under 1”.  

You can go back to 2010 and see how models usually don’t have much of a clue on snowfall beyond a day or two. Those headline model skill scores really don’t apply to East Coast storm tracks. We can remember how suppressed the Euro was for January 2016 and the actual totals were more than double what the Euro had a day before. Remember how some people didn’t want to believe the amped up NAM which was correct. Or when the Euro had an historic NYC snowfall in January 2015 but a wide miss with heavier totals east.

But you are correct in a sense that models usually don’t  completely miss storms. Unless we go back to January 2000. But P-types and amounts are usually in play sometimes right up to nowcast time.

Posters west of NYC hesitant to give the Euro high scores on this original Euro first guess

 

 

[psv88]

5 minutes ago, MJO812 said:

Yikes. Lots of weenie suicides by the northwest crew if this verifies 

[HeadInTheClouds]

10 minutes ago, psv88 said:

It’s weird how you keep ignoring that the Canadian models gave the city zero snow until today. Why is that?

I'm not ignoring anything. I already stated that an east shift caused the NYC metro and points east to get some snow instead of nothing because of a very tight gradient where even a small shift could have big implications. Other areas of the sub forum remained essentially the same. 

[SnowGoose69]

35 minutes ago, the_other_guy said:

what is upton doing?

 

They’re gonna go right into a winter storm warning? Kind of negates the whole reason for the watch if you hold off on issuing it.

Everything north of the Bronx should’ve been on a winter storm watch since yesterday.

I think they'll probably go advisories everywhere currently not in a watch, its possible the NJ county areas not currently in the watch and maybe SRN Westchester and SRN Fairfield could get 6 and reach warning but I would not be confident enough at the moment to have them in a warning.  Western Passaic and Western Bergen should get 6, eastern maybe not.   NYC has no bust potential on their western counties really, Mt Holly does if this comes east for sure.

[psv88]

2 minutes ago, bluewave said:

Again, models have been all over the place with snowfall amounts and the placement of those amounts. You can see why posters west of I-95 would be hesitant to give the Euro high marks based on this original suppression forecast and under 1”.  

You can go back to 2010 and see how models usually don’t have much of a clue on snowfall beyond a day or two. Those headline model skill scores really don’t apply to East Coast storm tracks. We can remember how suppressed the Euro was for January 2016 and the actual totals were more than double what the Euro had a day before. Remember how some people didn’t want to believe the amped up NAM which was correct. Or when the Euro had an historic NYC snowfall in January 2015 but a wide miss with heavier totals east.

But you are correct in a sense that models usually don’t  completely miss storms. Unless we go back to January 2000. But P-types and amounts are usually in play sometimes right up to nowcast time.

Posters west of NYC hesitant to give Euro high scores on this original Euro first guess

 

 

That was a 7 day forecast! We are talking day 5 or less. Stop. Even 7 days out it showed the potential for a light even area wide, which generally is correct 

[brooklynwx99]

ECMWF is a really nice hit. 3-6" area wide

[MANDA]

5 minutes ago, psv88 said:

Yikes. Lots of weenie suicides by the northwest crew if this verifies 

I'm playing it more conservative than most around my area.  Still going with 4-6".  There is still model uncertainty and this is going to be a fast mover.  Dynamics are good but not off the charts.  I'm comfortable with 4-6" around here.  We'll see how it plays out.