January 19th-20th: 1st Call Snow Map

sroc4 wrote:Im holding steady for now with the colder NAM soln.  NAM insisted that last nights little clipper would stay all snow for LI whereas  pretty much all others remained warm.  Im still flurrying now when it should have transitioned to rain by now.  

You know, I was JUST thinking about this very thing this morning. Most, if not all models besides the NAM, had the clipper producing rain anywhere south of I-78 by 1-2 AM. In reality, the snow was basically area-wide, with minimal changeover at the very end on the immediate coast.

Could this perhaps be a signal moving into this next storm? It may be wishful thinking, but I would love if any more experienced members would chime in on this.

Biggest takeaways for me:

1. NAM largely held serve
2. Hi-res RGEM and HRDPS are both still at their extended ranges and love to amplify storms like their parent model, GEM with a warm bias
3. The SREFs came in notably COLDER, even than their previous run, which, as I’ve stated multiple times, is a serious red flag to be on the lookout for colder solutions
4. With such a tight thermal gradient and inherent model wobbles, aside from the SREFs, NOTHING HAS TRENDED ANYWHERE today. Typical wobbles at this range from run to run are anywhere from 10-40 miles with surface tracks, and with such a tight thermal gradient these changes are exacerbated.
5. I’ll be looking at the Euro and UKMET, but other than that, I believe GFS and GEM are too warm too quick and am throwing them out

Gfs is most likely to warm and the Nam to cold. I will just hope not much ice but have a feeling I will see more of that then snow.

CPcantmeasuresnow wrote:

Frank_Wx wrote:The latest GFS is very warm. It tracks the low actually N&W of NYC. Everyone is raining.

Well I'm getting to the point where I don't believe any run on any model for this storm. I never bought the colder runs and I'm not buying this one either.

Since a lot of the previous runs have had over a half inch of ice for many areas bring on the rain over that.

I agree, the hell with this storm if what it's going to produce is a all that damn ice. Mother nature can keep it and just give us rain instead. A house with my wife 3 pets and no generator. I do not need a power outage. I have a fireplace, but that will only help so much.

rb924119 wrote:3. The SREFs came in notably COLDER, even than their previous run, which, as I’ve stated multiple times, is a serious red flag to be on the lookout for colder solutions

Hi rb, is there any map you could post that shows the SREFs? Or could you or anyone else provide a brief insight into the function of this particular model? Has it performed well in predicting previous storms? It's one that I am pretty unfamiliar with.

Secondly, up to this point, my initial thoughts have gotten me this far with this system. As it stands my expected axis of heaviest snow is only off by about 40 miles from the model consensus, and the NAM, SREF, GEFS all make a strong argument for me here. I see no reason to abandon my original thinking as of yet, and will therefore stay the course for now.

One last point, seeing the GFS Ensembles consistently significantly colder and snowier than the Op is yet another red flag to me that it’s off it’s rocker. We shall see what the next 24 hours hold.

Let's take a look at the setup we have a 1037 MB high pressure sitting in Quebec in late January perfect spot cold at all levels of the atmosphere we have a warm juicy Southern stream system but not strong it's very weak with pretty good warm air advection so where do you think a model with err. On the cold side or the warm side? Just going from my past experiences and following weather for many years I think the models would err  on the warm side as it's hard to push these Arctic highs out. Any delay in the warm air reaching the mid-levels would mean significantly more snow I do ultimately think it flips at some point but I think we get a good front end thump and then we'll see where the ice rain line sets up. This is going to be a great Now cast storm even if it won't be all snow for a lot of us

DAYBLAZER wrote:

rb924119 wrote:3. The SREFs came in notably COLDER, even than their previous run, which, as I’ve stated multiple times, is a serious red flag to be on the lookout for colder solutions

Hi rb, is there any map you could post that shows the SREFs? Or could you or anyone else provide a brief insight into the function of this particular model? Has it performed well in predicting previous storms? It's one that I am pretty unfamiliar with.

I can’t readily post images, but the SREFs are basically the NAM’s ensemble, just like the GFS and Euro have their ensembles. They have scored coups before, but generally are over-amplified. That’s why I made that point you quoted. If they are trending opposite of their known bias, that’s something I notice, and is where I find them highly helpful. I also like the critical thickness plots to help determine precipitation types.

I saw 3km nam brought a half inch frz back up into NYC area and northern nj. Its going to be nowcast.

Anybody 15 to 20 miles away from the coast is not going above freezing not in this setup and there's a good chance it doesn't to go above freezing even close to the coast

Once the low pressure feels the Confluence to our North when it's a over Kentucky or Tennessee There's no way it's going Northeast it's going east Northeast we shall see

News 12 has me all rain. Ill go piss and moan in the pen lol

algae888 wrote:Once the low pressure feels the Confluence to our North when it's a over Kentucky or Tennessee There's no way it's going Northeast it's going east Northeast we shall see

al what do you think for us? Do u believe the frz threat or too warm to actually accrue. Or will we see mainly snow or rain and no in between
This is all over the place.

Take a look at nynjpa weather's map bad news for many folks. She's 3 to 6 with 0.25 to 0.5 frz. Everyone is say diff things u less your upstate.

GEFS are pretty far west

DAYBLAZER wrote:

sroc4 wrote:Im holding steady for now with the colder NAM soln.  NAM insisted that last nights little clipper would stay all snow for LI whereas  pretty much all others remained warm.  Im still flurrying now when it should have transitioned to rain by now.  

You know, I was JUST thinking about this very thing this morning. Most, if not all models besides the NAM, had the clipper producing rain anywhere south of I-78 by 1-2 AM. In reality, the snow was basically area-wide, with minimal changeover at the very end on the immediate coast.

Could this perhaps be a signal moving into this next storm? It may be wishful thinking, but I would love if any more experienced members would chime in on this.

Yeah the forecast busted on QPF in some spots but the NAM did well handling the temp profile. Obv the set up this weekend is very diff but with the type of cold air we have to the north I just dont believe these warmer solns at all.

algae888 wrote:Anybody 15 to 20 miles away from the coast is not going above freezing not in this setup and there's a good chance it doesn't to go above freezing even close to the coast

Agree

The UK also came North it goes from Western Kentucky to Southeast PA then south of Long Island we need that east-northeast Trend when it's over Kentucky hopefully we can get a little more confluence to squeeze this South some

UKMET actually looks noticeably colder from what can tell so far, but I’m waiting on further maps to confirm.

algae888 wrote:The UK also came North it goes from Western Kentucky to Southeast PA then south of Long Island we need that east-northeast Trend when it's over Kentucky hopefully we can get a little more confluence to squeeze this South some

These heights up the coast are extremely amplified. Earlier in the day yesterday and most of Wednesday, it looked like the southern stream was trending to slow down so the TPV would out-run it. Now the two are in-sync. There is phasing on virtually all guidance.



The EURO, GFS, GEFS, and now UKMET are very warm for the area. The Hi-Res models are still trending toward a more northerly storm too.

rb924119 wrote:UKMET actually looks noticeably colder from what can tell so far, but I’m waiting on further maps to confirm.

Ah I see my error here, didn’t realize the forecast time segments changed from the 00z to the 12z lol it is a bit warmer I believe.

rb924119 wrote:

rb924119 wrote:UKMET actually looks noticeably colder from what can tell so far, but I’m waiting on further maps to confirm.

Ah I see my error here, didn’t realize the forecast time segments changed from the 00z to the 12z lol it is a bit warmer I believe.

A bit?

Do the isobars being closer together mean more snow or just stronger winds?

TheAresian wrote:Do the isobars being closer together mean more snow or just stronger winds?

Stronger winds

Thank you.

At what point do we start looking at what is actually happening upstream with the main pieces of energy, and how closely the models are getting those correct?