Snowfall NYC subforum Jan 6 and OBS if needed

[wdrag]

As of 730 PM Monday Dec 30, ensembles have faded a bit the past day or two of model cycles.  Snow event (minor) still could occur but suppression mostly south of us or delay til around the 8th. 

Snow may come in pieces Monday Jan 6-early 9th.  Slower seems more likely for our area around the 8th when more longitudinal 5H troughing approaches from the Great Lakes as per the NAEFS which has considerable Canadian model influence.   An important feature may be the apparently big short wave diving southeast from western Hud Bay around the 7th and how much backing of the flow will occur ahead of it when it is modeled into the upper Great Lakes by the 8th. 

Added ensembles (EPS and GEFS) for Monday the 6th--chance of 1" on the Canadian GEPS even less.  

Also the NWS D7 LOW chance for more than 1/4" of qpf which leads into the 6th.

The CPC 3PM/30 probabilistic hazard outlook points out a better chance 7th onward. 

Hopefully modeling will become more favorable for snowfall.  

This post is an attempt to grab the first possible snow of January 2025 in NYC but is issued with considerable uncertainty - less than usual confidence and only for the period of Jan 6-12z/9.  IF snow does occur (more than a Trace), then this  thread can serve as the observations.  

The tags have ice pellets added, in case Great Lakes 5h troughing around the 8th forces mid level above freezing temps into our area with one possible low center into the Great Lakes. 

720A/4 edited the headline to limit event to the 6th and dropped the ice pellet tag.  The event has at least held onto the 6h for timing since the initial Dec 30 post, but the max axis in PA-NJ has shifted south about 150 miles since the post started 6 days ago. That is worthy of keeping in mind when posting threads 6 days in advance... limits confidence of occurrence.  A positive  note the accuracy of the D7 WPC chance of 1/4" frozen in the Ohio Valley!

[nianticct]

New years resolution think positive! Go snow ! Go Georgetown!

[NEG NAO]

Seems like the 0Z Canadian is moving towards the 12Z Euro solution but still 7 plus days out and the timing is different - waiting for the 0Z Euro which has had similar runs  2 cycles in a row

[MJO812]

[NEG NAO]

18 minutes ago, MJO812 said:

yes seems like some models moving towards 12Z Euro solution - waiting to see if 0Z Euro is similar to 12Z and last nights 0Z --- moving into medium range forecasting range close to 7 days out........

[NEG NAO]

The 0Z GFS moved towards previous Canadian solutions of the past couple of days - not a flake here throughout...showing the confusion in the modeling run to run

[NEG NAO]

OZ EURO now has mid-Atlantic Snowstorm south of us which  might work in our favor since who wants to be in the bulleye 7 days out ?? and these things usually trend north in time MAYBE ! 

[NEG NAO]

0Z Euro has a second LP late next week which originated in the GOM crawls up the coast - who knows if this is even real

[snowman19]

Obviously not 100% fool proof everytime, but I think the old Bernie Rayno snowstorm rule is pretty accurate. You get snow on either the front side or back side of arctic outbreaks. So it usually either comes immediately following an arctic cold injection as the blocking is setting up or just as the blocking is breaking down and the cold is pulling out. Does that rule work out this time? Who knows

[wdrag]

NWS 07Z/31 Blend of Models (BOM) snowfall attached. 

06Z/31 GFS op back in the game a little bit.  Variable solutions and so for me patience to wait it out.

Am pretty sure the 5H flow will back to between 250-270 degrees and confluence lift north by 00z/9 permitting improved opportunity the 7th-8th greater than that of the potentially dried out first shot that tends to stay south of I80. Uncertainty. Here's the BOM.

.

[bluewave]

32 minutes ago, snowman19 said:

Obviously not 100% fool proof everytime, but I think the old Bernie Rayno snowstorm rule is pretty accurate. You get snow on either the front side or back side of arctic outbreaks. So it usually either comes immediately following an arctic cold injection as the blocking is setting up or just as the blocking is breaking down and the cold is pulling out. Does that rule work out this time? Who knows

This may turn into a game of how much spacing we get between the individual shortwaves with so many systems in the fast Northern Stream flow and strong 50/50 low.

[Tatamy]

20 minutes ago, wdrag said:

NWS 07Z/31 Blend of Models (BOM) snowfall attached. 

06Z/31 GFS op back in the game a little bit.  Variable solutions and so for me patience to wait it out.

Am pretty sure the 5H flow will back to between 250-270 degrees and confluence lift north by 00z/9 permitting improved opportunity the 7th-8th greater than that of the potentially dried out first shot that tends to stay south of I80. Uncertainty. Here's the BOM.

.

06Z/31 EC illustrates your point very well.

[wdrag]

Only 1 EPS cycle so NOT in Stone... but its faster and further N with measurable to NYC by midnight Monday morning. NOT ETCHED in stone... but I think we're at least temporarily in the game  for a snow event next Monday. 

[Allsnow]

56 minutes ago, bluewave said:

This may turn into a game of how much spacing we get between the individual shortwaves with so many systems in the fast Northern Stream flow and strong 50/50 low.

Euro was further north at 06z then 00z this morning. ironically, the cutter/ridge pattern since 2019 can helps us in this set up with getting the system further north 

[RU848789]

1 hour ago, wdrag said:

NWS 07Z/31 Blend of Models (BOM) snowfall attached. 

06Z/31 GFS op back in the game a little bit.  Variable solutions and so for me patience to wait it out.

Am pretty sure the 5H flow will back to between 250-270 degrees and confluence lift north by 00z/9 permitting improved opportunity the 7th-8th greater than that of the potentially dried out first shot that tends to stay south of I80. Uncertainty. Here's the BOM.

.

Minor point, but the BOM graphic has no title on it, so one can't see what run it is nor how far out the run goes - wondering if it's "snipped" instead of copied/pasted.  Looks like it's today's 07Z run thru 1/9 at 0Z.  Completely agree patience is key here with so many models/solutions and still being 7+ days out.  

[MJO812]

3 minutes ago, Allsnow said:

Euro was further north at 06z then 00z this morning. ironically, the cutter/ridge pattern since 2019 can helps us in this set up with getting the system further north 

Eps is also more amplified than 0z. 

[wdrag]

47 minutes ago, RU848789 said:

Minor point, but the BOM graphic has no title on it, so one can't see what run it is nor how far out the run goes - wondering if it's "snipped" instead of copied/pasted.  Looks like it's today's 07Z run thru 1/9 at 0Z.  Completely agree patience is key here with so many models/solutions and still being 7+ days out.  

Very good point... I tend to be in a hurry... how's this for us local folks. 

[EastonSN+]

4 hours ago, snowman19 said:

Obviously not 100% fool proof everytime, but I think the old Bernie Rayno snowstorm rule is pretty accurate. You get snow on either the front side or back side of arctic outbreaks. So it usually either comes immediately following an arctic cold injection as the blocking is setting up or just as the blocking is breaking down and the cold is pulling out. Does that rule work out this time? Who knows

Usually on one side you have a chance for a minor to moderate event and on the other side you have a chance of a major event.

[MJO812]

Icon more north

[LibertyBell]

4 hours ago, snowman19 said:

Obviously not 100% fool proof everytime, but I think the old Bernie Rayno snowstorm rule is pretty accurate. You get snow on either the front side or back side of arctic outbreaks. So it usually either comes immediately following an arctic cold injection as the blocking is setting up or just as the blocking is breaking down and the cold is pulling out. Does that rule work out this time? Who knows

Has it ever happened both on the front and the back side?

Maybe in 1995-96 and 2010-11?

 

[Allsnow]

Perfect spot to be 

[gravitylover]

5 minutes ago, MJO812 said:

And there's me, smoking virga. Keep moving north  

[LibertyBell]

11 minutes ago, EastonSN+ said:

Usually on one side you have a chance for a minor to moderate event and on the other side you have a chance of a major event.

1995-96 and 2010-11 had major ones on both sides.

8-14 in December 1995 , 20-32 in January 1996

18-30 in December 2010, 15-20 in January 2011

 

 

[EastonSN+]

Just now, LibertyBell said:

1995-96 and 2010-11 had major ones on both sides.

8-14 in December 1995 , 20-32 in January 1996

18-30 in December 2010, 15-20 in January 2011

 

 

The great thing about 2010-2011 and what I learned in the New England forum is that we went from one good setup which is represented in the two events you have posted and we went into a second good setup which allowed for the KU event at the end of January. Then we ended up with two smaller events with a changeover event in February and a moderate overrunning event in March great year.

[LibertyBell]

4 minutes ago, EastonSN+ said:

The great thing about 2010-2011 and what I learned in the New England forum is that we went from one good setup which is represented in the two events you have posted and we went into a second good setup which allowed for the KU event at the end of January. Then we ended up with two smaller events with a changeover event in February and a moderate overrunning event in March great year.

The greatest and longest duration snow cover I've ever seen!  My backyard had so much snow that it looked like the snow was up to my windows!  You rarely if ever see that around here on the south shore.

 

 

[Allsnow]

Carolina crusher on the gfs 

[EastonSN+]

[Voyager]

38 minutes ago, gravitylover said:

And there's me, smoking virga. Keep moving north  

We just need 75 miles. Is it doable, though?

[MJO812]

9 minutes ago, Allsnow said:

Carolina crusher on the gfs 

Gfs always overdoses confluence. Let's see if this happens here. 

[Allsnow]

Just now, MJO812 said:

Gfs always overdoses confluence. Let's see if this happens here. 

CMC going to be similar to the icon