Minor snow possible sunday 12/14/25

[mob1]

43 minutes ago, jm1220 said:

That doesn’t cause high ratios. You want temps between -12 and -18C in the clouds where snowflakes are made which promotes good snow growth, and plenty of moisture/lift in that layer. If temps are higher or lower it will hurt ratios. I remember a few times temps were in the low 20s or even teens but we had tiny sand or needle flakes that were 10-1 ratio. 

Here's the sounding from the GFS for his area (roughly), that's actually decent temps for the dendritic growth zone but the winds at height probably argue against really good ratios.

Precipitation rates also come into play here as you'd need something heavier (like the NAM shows) to get proper dynamic cooling. Light rates with a surface temperature of just about freezing won't do much. 

A general rule that would serve people well is that for coastal areas the ratios don't usually exceed the standard 10-1. There any obviously plenty of exceptions but more often than not it's best to ignore ratios for the coastal plain.

[David-LI]

47 minutes ago, WeatherGeek2025 said:

all levels will be below freezing during the storm!

Normal ratio for this storm

[wthrmn654]

Reading the last few pages will give anyone a headache jeez!  

[North and West]

According to what?

drugs


.

[Jersey_Snowhole]

Why dos the euro always get stuck at hr 51 on weather bell

[bluewave]

This looks like it could actually thread the needle. Kicker coming into BC probably will prevent the low from riding too far north. The weak ridge to our east will work against a complete suppression to the south. So a 2” scenario like the 12z Euro has in NYC would be a decent outcome for such a fast Pacific flow pattern. Perhaps there is a 1” downside -upside risk for a 1-3” event in NYC.

[Krs4Lfe]

2 minutes ago, bluewave said:

This looks like it could actually thread the needle. Kicker coming into BC probably will prevent the low from riding too far north. The weak ridge to our east will work against a complete suppression to the south. So a 2” scenario like the 12z Euro has in NYC would be a decent outcome for such a fast Pacific flow pattern. Perhaps there is a 1” downside -upside risk for a 1-3” event in NYC.

When do you think this fast Pacific flow pattern will ease up a bit? Back in the 2010s, there used to be bowling balls traversing the US when there was this much cold air. Now; we’re stuck with clippers. Only have had to shovel snow a handful of times since 2020. 

[jm1220]

31 minutes ago, mob1 said:

Here's the sounding from the GFS for his area (roughly), that's actually decent temps for the dendritic growth zone but the winds at height probably argue against really good ratios.

Precipitation rates also come into play here as you'd need something heavier (like the NAM shows) to get proper dynamic cooling. Light rates with a surface temperature of just about freezing won't do much. 

A general rule that would serve people well is that for coastal areas the ratios don't usually exceed the standard 10-1. There any obviously plenty of exceptions but more often than not it's best to ignore ratios for the coastal plain.

Yep good point, strong winds break apart the flakes which causes poor ratios. 

[bluewave]

4 minutes ago, Krs4Lfe said:

When do you think this fast Pacific flow pattern will ease up a bit? Back in the 2010s, there used to be bowling balls traversing the US when there was this much cold air. Now; we’re stuck with clippers. Only have had to shovel snow a handful of times since 2020. 

Don’t really know since it has become such a persistent feature since the 2018-2019 winter.

[CPcantmeasuresnow]

1 hour ago, bluewave said:

Don’t really know since it has become such a persistent feature since the 2018-2019 winter.

Has there been a comparable period for this feature, for this long a period in our observable past?

[eduggs]

Noticable shift ESE with the PV on the 18z NAM. Looks more suppressive. Bummer... was really hoping to get lucky with this one and keep trending it. Although it shouldn't be surprising that the outlier solutions shift towards model consensus.

[WeatherGeek2025]

nam doesn't look good

[winterwx21]

We knew that the 12z NAM was likely overdone. 18z NAM looks fine ... a 2 to 4 inch snowfall is what we're looking for from this type of system. 

[WeatherGeek2025]

1 minute ago, winterwx21 said:

We knew that the 12z NAM was likely overdone. 18z NAM looks fine ... a 2 to 4 inch snowfall is what we're looking for from this type of system. 

i think that's a great call 2-4 inches and you know what if we get that we should be happy with it. especially with what we got in the last 5 years!

[WeatherGeek2025]

[North and West]

nam doesn't look good

Can you include context moving forward? Sometimes I don’t need to add this board into my daily doomscrolling.


.

[mikem81]

RGEM looks great and its 100 times better than the NAM

[BoulderWX]

12 minutes ago, mikem81 said:

RGEM looks great and its 100 times better than the NAM

Its another 2-4" depiction; people shouldn't fret over each run of each model; this is a 1-3 or 2-4 event for most - just sit back and enjoy a little holiday snow

[Big Jims Videos]

a three inch snowfall event at my place would be the most we've gotten in almost 3 winters. 

[MJO812]

Icon is better

[Franklin0529]

4 minutes ago, Big Jims Videos said:

a three inch snowfall event at my place would be the most we've gotten in almost 3 winters. 

Yup I'm right up in Hazlet. Been horrible 

[MJO812]

Gfs slightly better

[eduggs]

FWIW, big improvement on the 18z RRFS vs. 12z... now generally in line with NAM and RGEM.

[Stormlover74]

8 minutes ago, MJO812 said:

Gfs slightly better

It went from like .5 to .75 to 1". By Sunday it'll be in line with the other models

[RU848789]

The NWS finally issued their first snowfall map that goes through the end of the storm and, as expected, they're generally in the 1-3" range with the lower amounts well NW of 95 (less precip) and the higher end of the range along and SE of 95 (and SW of Philly), but anyone who has seen the models knows that 3-5" amounts are still on the table if the coastal stays close enough to the coast.  Good NWS discussion highlighting the range of possibilities is below.

Area Forecast Discussion National Weather Service Mount Holly NJ 231 PM EST Thu Dec 11 2025

The forecast gets more complicated for the Saturday night through Sunday period as there will be several different things at play. In the upper levels, there will be an upper level trough digging as it moves from the Great Lakes region towards the east coast. Meanwhile at the surface level, there will be an arctic front pushing into the area from the NW as low pressure pivots through Quebec into northern New England. Forecast guidance continues to indicate that a wave of low pressure will form farther south near the front as it`s moving through the mid Atlantic region Saturday night into Sunday morning. However there are differences regarding the strength and track of this system. The latest GFS continues to indicate that the low may not really get going until it`s off the coast and if this were to verify, most of the precip with the system would be near and south of the I-95 corridor but mainly fall as snow. The NAM is at the other end of the spectrum indicating a stronger low forming near Delmarva. This would keep the heaviest precip with the system north of the urban corridor with lighter amounts and more of a snow/rain mix farther south. The 12z RGEM lies in between these two extremes. There`s also a wide variation in the ensembles. Given this continuing uncertainty, we largely stayed close to the NBM. And the bottom line with this forecast is that we do expect precip to move in either late Saturday evening or overnight Saturday night. It should be mainly snow except near the coast where some mixing with rain is likely...especially at the onset. And if arrives early enough Saturday evening, some rain or mixing could also occur near the urban corridor. The bulk of the precip falls overnight Saturday night through the first half of Sunday morning. This had been looking like a light precip event but some of the latest guidance has also beefed up QPF amounts into the .25 to .50 inch range. The big questions though are where the highest amounts will fall and how this will translate to snowfall. We admittedly still lean a little on the conservative side with forecast snow amounts and continue to indicate a fairly widespread 1-3 inches falling across the area. There is the potential though that some areas could see snow amounts in the 3 to 5 inch range given the general uptick in forecast QPF. The big question though is where these amounts occur. A more northern track would result in these higher occuring over eastern PA into northern NJ where a more southern track would favor higher amounts along the coastal plain. At this point, the main thing to stress is this continuing uncertainty in the details despite overall moderate confidence in there being an accumulating snowfall event affecting the area.

[TJW014]

3 minutes ago, RU848789 said:

The NWS finally issued their first snowfall map that goes through the end of the storm and, as expected, they're generally in the 1-3" range with the lower amounts well NW of 95 (less precip) and the higher end of the range along and SE of 95 (and SW of Philly), but anyone who has seen the models knows that 3-5" amounts are still on the table if the coastal stays close enough to the coast.  

"finally"
Anybody who posts a snowfall map over 3 days in advance is dumb.  

[jm1220]

4 minutes ago, RU848789 said:

The NWS finally issued their first snowfall map that goes through the end of the storm and, as expected, they're generally in the 1-3" range with the lower amounts well NW of 95 (less precip) and the higher end of the range along and SE of 95 (and SW of Philly), but anyone who has seen the models knows that 3-5" amounts are still on the table if the coastal stays close enough to the coast.  Good NWS discussion highlighting the range of possibilities is below.

Area Forecast Discussion National Weather Service Mount Holly NJ 231 PM EST Thu Dec 11 2025

The forecast gets more complicated for the Saturday night through Sunday period as there will be several different things at play. In the upper levels, there will be an upper level trough digging as it moves from the Great Lakes region towards the east coast. Meanwhile at the surface level, there will be an arctic front pushing into the area from the NW as low pressure pivots through Quebec into northern New England. Forecast guidance continues to indicate that a wave of low pressure will form farther south near the front as it`s moving through the mid Atlantic region Saturday night into Sunday morning. However there are differences regarding the strength and track of this system. The latest GFS continues to indicate that the low may not really get going until it`s off the coast and if this were to verify, most of the precip with the system would be near and south of the I-95 corridor but mainly fall as snow. The NAM is at the other end of the spectrum indicating a stronger low forming near Delmarva. This would keep the heaviest precip with the system north of the urban corridor with lighter amounts and more of a snow/rain mix farther south. The 12z RGEM lies in between these two extremes. There`s also a wide variation in the ensembles. Given this continuing uncertainty, we largely stayed close to the NBM. And the bottom line with this forecast is that we do expect precip to move in either late Saturday evening or overnight Saturday night. It should be mainly snow except near the coast where some mixing with rain is likely...especially at the onset. And if arrives early enough Saturday evening, some rain or mixing could also occur near the urban corridor. The bulk of the precip falls overnight Saturday night through the first half of Sunday morning. This had been looking like a light precip event but some of the latest guidance has also beefed up QPF amounts into the .25 to .50 inch range. The big questions though are where the highest amounts will fall and how this will translate to snowfall. We admittedly still lean a little on the conservative side with forecast snow amounts and continue to indicate a fairly widespread 1-3 inches falling across the area. There is the potential though that some areas could see snow amounts in the 3 to 5 inch range given the general uptick in forecast QPF. The big question though is where these amounts occur. A more northern track would result in these higher occuring over eastern PA into northern NJ where a more southern track would favor higher amounts along the coastal plain. At this point, the main thing to stress is this continuing uncertainty in the details despite overall moderate confidence in there being an accumulating snowfall event affecting the area.

Reasonable at this point. Hopefully it amps up a little more and we can get those 3"+ amounts.