Extreme Cold, Snow & Sleet: SECS 1/25 - 1/26

[Stormlover74]

Just now, WeatherGeek2025 said:

reggie?

 

 

eedit/:::brrrrrr outside

Not running yet for some reason

Went from 36 to 19 in thr past 4 hours 

[SnoSki14]

Just now, psv88 said:

The NAM is totally out on its own. The other models are trending colder and snowier. 

I'll give what it shows tomorrow a lot more weight than tonight but it's great at picking up warm layers so we can't discount it

[Winterweatherlover]

Just now, WeatherGeek2025 said:

reggie?

 

 

eedit/:::brrrrrr outside

Seems delayed

[Volcanic Winter]

Haven’t had a chance to read the forums today but have stayed with the model runs; any thoughts on why the NWS maps are so aggressive? Well south of me in Toms River is still coded 10-15, and that just doesn’t seem likely based on the majority of guidance. Are they weighing the GFS more because it seemed to hold to a snowier outcome? 
 

Just being cautious? This is a tough one thing to pin down exact mix lines / lanes, any wiggle could shift totals - so logically surmising they’re just playing safe? Just seems awfully aggressive. 

[Blizzardo]

2 minutes ago, donsutherland1 said:

And the GFS was first to bring it back. For a time, it was the only model showing a big storm, but its solutions were dismissed on grounds that they were the result of initialization errors.

Yea I remember one model still had it... Lol

[Winterweatherlover]

1 minute ago, psv88 said:

The NAM is totally out on its own. The other models are trending colder and snowier. 

Seems they are mostly holding steady as opposed to trending any particular way. Either way yes the NAM seems to be the outlier now, although if it's the outlier 24 hours from now I'd take it more seriously.

[SACRUS]

Cold push

 

[Blizzardo]

Sometimes the NAM hits on these big ones... Just saying... 

[WeatherGeek2025]

I think tonight's probably gonna be the coldest night of the year in terms of windchill because of the wind. It's very very brutal outside.

[psv88]

1 minute ago, Winterweatherlover said:

Seems they are mostly holding steady as opposed to trending any particular way. Either way yes the NAM seems to be the outlier now, although if it's the outlier 24 hours from now I'd take it more seriously.

I mean the icon added 3-4”’of snow on Long Island. That’s a solid increase. 

[Tatamy]

12 minutes ago, psv88 said:

That’s colder 

Check out the precip types on that model (RRFS).  The totals shown do not match that or reflect the temperatures aloft.  The snow totals are way overstated.  They are basically another NAM - maybe worse.

[Winterweatherlover]

3 minutes ago, Volcanic Winter said:

Haven’t had a chance to read the forums today but have stayed with the model runs; any thoughts on why the NWS maps are so aggressive? Well south of me in Toms River is still coded 10-15, and that just doesn’t seem likely based on the majority of guidance. Are they weighing the GFS more because it seemed to hold to a snowier outcome? 
 

Just being cautious? This is a tough one thing to pin down exact mix lines / lanes, any wiggle could shift totals - so logically surmising they’re just playing safe? Just seems awfully aggressive. 

Depends on who gets the best rates in terms of the initial thump. Theres definitely a scenario where coastal NJ could get similar totals to NYC in this setup if their rates are better. 

[Jt17]

Haven’t had a chance to read the forums today but have stayed with the model runs; any thoughts on why the NWS maps are so aggressive? Well south of me in Toms River is still coded 10-15, and that just doesn’t seem likely based on the majority of guidance. Are they weighing the GFS more because it seemed to hold to a snowier outcome? 
 
Just being cautious? This is a tough one thing to pin down exact mix lines / lanes, any wiggle could shift totals - so logically surmising they’re just playing safe? Just seems awfully aggressive. 

I think part of it is that the front end thump should have some high ratios and people in here assume that since sleet shows up that the whole storm is warm now. The onset is going to be high ratio snow and could pile up more quickly than people think.


.

[MJO812]

Down to 18

[Winterweatherlover]

Another thing is usually if you are near the sleet/snow line the reality is there will be flips back and forth between snow and sleet and some mixing at the same time rather than simply hours of only sleet on one side of the line and only snow on the other. The models don't really capture this nuance I don't think.

[Volcanic Winter]

Just now, Jt17 said:

I think part of it is that the front end thump should have some high ratios and people in here assume that since sleet shows up that the whole storm is warm now. The onset is going to be high ratio snow and could pile up more quickly than people think.


.

Definitely; the thump will be fun regardless. Would need 5 hours of 2”/hr to hit 10, the low max of NWS forecast. 

Definitely seems aggressive to me, not judging - I certainly wouldn’t want to be the one making any calls for NJ / LI / NYC, just noting. 

[Volcanic Winter]

1 minute ago, MJO812 said:

Down to 18

24 here but dropping fast 

[psv88]

4 minutes ago, Tatamy said:

Check out the precip types on that model (RRFS).  The totals shown do not match that or reflect the temperatures aloft.  The snow totals are way overstated.  They are basically another NAM - maybe worse.

I’m comparing the ICON to the ICON. Its algorithms didn’t change from 18z to 0z. 

[Blizzardo]

2 minutes ago, Jt17 said:

I think part of it is that the front end thump should have some high ratios and people in here assume that since sleet shows up that the whole storm is warm now. The onset is going to be high ratio snow and could pile up more quickly than people think.


.

This is it exactly... 2" per hour at 15:1 adds up real quick... 

[Winterweatherlover]

Just now, Volcanic Winter said:

Definitely; the thump will be fun regardless. Would need 5 hours of 2”/hr to hit 10, the low max of NWS forecast. 

Definitely seems aggressive to me, not judging - I certainly wouldn’t want to be the one making any calls for NJ / LI / NYC, just noting. 

Agree I think upton is being too aggressive and Mount Holly even more aggressive. They are probably being cautious to alert the public and will back down a little tomorrow if current modeling holds.

[Snowlover11]

So far the NAM is the warmest model, while others have inched better. Lets see how the GFS,UKMET and EURO do here.

[jm1220]

3 minutes ago, Tatamy said:

Check out the precip types on that model.  The totals shown do not match that or reflect the temperatures aloft.  The snow totals are way overstated.  They are basically another NAM - maybe worse.

It gets sleet from a line from Port Jervis to just south of Boston. If sleet really gets that far north it's hard to see how the immediate NYC area and coast do well.

[Stormlover74]

This is what falls as snow on the rrfs. Then it flips and we get a ton of sleet

[JonClaw]

I don't know how useful SREF plumes are, but they have a wide range for snow at LGA: 4" to 22" with a 12.4" mean.

[Blizzardo]

2 minutes ago, Volcanic Winter said:

Definitely; the thump will be fun regardless. Would need 5 hours of 2”/hr to hit 10, the low max of NWS forecast. 

Definitely seems aggressive to me, not judging - I certainly wouldn’t want to be the one making any calls for NJ / LI / NYC, just noting. 

That at 10:1 ratio... It's gonna be 15:1 atleast when this gets going. But how long that lasts is anyone's guess..

[greenmtnwx]

2 minutes ago, Blizzardo said:

This is it exactly... 2" per hour at 15:1 adds up real quick... 

how much does 2” per hour at 10:1 add up to in 3 hours? 

[Tatamy]

2 minutes ago, psv88 said:

I’m comparing the ICON to the ICON. Its algorithms didn’t change from 18z to 0z. 

Yeah Icon was fine.

[Blizzardo]

1 minute ago, greenmtnwx said:

how much does 2” per hour at 10:1 add up in 3 hours? 

This a trick question? Lol

[psv88]

2 minutes ago, Stormlover74 said:

This is what falls as snow on the rrfs. Then it flips and we get a ton of sleet

As @NorthShoreWxsaid, there may be times where it’s a snow/sleet mix. So that purple is a mix rather than pure sleet. Very rate dependent. If you’re under a big band you’ll flip back to snow IMO

[Blizzardo]

3 minutes ago, greenmtnwx said:

how much does 2” per hour at 10:1 add up in 3 hours? 

How much is 2 inch per hour at 15:1 in 3 hours??