01/22/16-01/23/16 Update #1 - Historic Storm Possible

More than 50% inside and more amped than even the Op, which would steer the surface low further north, especially when compared to the mean.....

18z Ensemble MEAN:

NjWeatherGuy wrote:Holy crap, 35-45mph sustained winds inland...

http://mp1.met.psu.edu/~fxg1/GFS13PA_18z/gfsloop.html#picture

That is nuts, why so far inland of NJ but not so far inalnd of NYC? Still I see period of 25-40kt winds sustained, wouldnt be surprised if this holds to see hurricane gusts. UN PRE CI DEENTED!!! And keep those totals going up I want that roid but I guess ill settle for a godzilla lol, PA gets Frankzilla dear lord, imagine we get that over here somehow.

rb924119 wrote:18z Ensemble MEAN:

Why are these amounts so much lower, is this high for this map? Also the one with the white why is it only showing 12 inches, or is the white area highest impact area? Sorry one more thing do not understand NESIS 5 is that like saying a category 5 hurricane but in snow impact? I know not in winds but man I cannot get over how high there are modeled and consistently, I love that people are actually talking about it, usually I mention winds and everyone says it wont happen lol.

You know whats odd, JB isn't going nuts on twitter posting snow maps etc. Not even mentioning much.

RB I'm assuming that's not good for the coastal sections

jmanley32 wrote:

NjWeatherGuy wrote:Holy crap, 35-45mph sustained winds inland...

http://mp1.met.psu.edu/~fxg1/GFS13PA_18z/gfsloop.html#picture

That is nuts, why so far inland of NJ but not so far inalnd of NYC? Still I see period of 25-40kt winds sustained, wouldnt be surprised if this holds to see hurricane gusts. UN PRE CI DEENTED!!! And keep those totals going up I want that roid but I guess ill settle for a godzilla lol, PA gets Frankzilla dear lord, imagine we get that over here somehow.

Coastal plain in NJ but upstate NY is more elevation"y" is why Id suspect winds would be higher, in addition to most of NJ being closer to the SLP.

RB TALKING REAL DIRTY!!!!!
LOVE IT - SORRY ABOUT THAT FOR THE 12Z KID JUST WAS IN THE ZONE AND WE SHOULD HAVE A GENTS AGREEMENT THAT FOR SUCH A BIG WEATHER EVENT WE JUST DO DISCO PBP NO QUESTIONS OR SUCH JUST MAPS AND PBP OF THE H5 AND H7 ETC!

Frank....are you still planning a live chat tomorrow night?

NjWeatherGuy wrote:

jmanley32 wrote:

NjWeatherGuy wrote:Holy crap, 35-45mph sustained winds inland...

http://mp1.met.psu.edu/~fxg1/GFS13PA_18z/gfsloop.html#picture

That is nuts, why so far inland of NJ but not so far inalnd of NYC? Still I see period of 25-40kt winds sustained, wouldnt be surprised if this holds to see hurricane gusts. UN PRE CI DEENTED!!! And keep those totals going up I want that roid but I guess ill settle for a godzilla lol, PA gets Frankzilla dear lord, imagine we get that over here somehow.

Coastal plain in NJ but upstate NY is more elevation"y" is why Id suspect winds would be higher, in addition to most of NJ being closer to the SLP.

No I literally mean just 15 miles inland the stronger winds go thats not elevation, and the winds slacken off the further north u go. Whatever, still gonna be blitzing, 25-40 sustained in this area in a snowstorm is near unheard of. NJ even has some 60kt along coast, but that might b over water only.

Biggin23 wrote:Frank....are you still planning a live chat tomorrow night?

Wednesday night

Frank_Wx wrote:

Biggin23 wrote:Frank....are you still planning a live chat tomorrow night?

Wednesday night

Sounds good...need to block the calendar, LOL 

frank i surely hope the storm is still strong as hell Wednesday night

jake732 wrote:frank i surely hope the storm is still strong as hell Wednesday night

Ryan Maue just tweeted that at this point models are not going to change much. moreso 5+ days out. I think either things trend better or they stay the same, win win as frank said.

GEFS still has a few badly suppressed solutions skewing the mean to the SE. Most are quite healthy hits but we'll have to watch whether the amount of those misses decreases.

amugs wrote:RB TALKING REAL DIRTY!!!!!
LOVE IT - SORRY ABOUT THAT FOR THE 12Z KID JUST WAS IN THE ZONE AND WE SHOULD HAVE A GENTS AGREEMENT THAT FOR SUCH A  BIG WEATHER EVENT WE JUST DO DISCO PBP NO QUESTIONS OR SUCH JUST MAPS AND PBP OF THE H5 AND H7 ETC!

Sorry about what, mugs? lol

I don't want it so close to coast looks like their may be mixing issues

I am on the bus going home from work. I haven't had much chance to view this forum until now. All I can say is...wow!

jmanley32 wrote:

rb924119 wrote:18z Ensemble MEAN:

Why are these amounts so much lower, is this high for this map? Also the one with the white why is it only showing 12 inches, or is the white area highest impact area?  Sorry one more thing do not understand NESIS 5 is that like saying a category 5 hurricane but in snow impact? I know not in winds but man I cannot get over how high there are modeled and consistently, I love that people are actually talking about it, usually I mention winds and everyone says it wont happen lol.

1. They're lower because it's an ensemble mean. The GFS ensemble has 21 separate members, each of which is identical to the Op but run with a single slight change to the initial conditions. For example, one member has a slight faster 200mb jet, another has the 500mb energy stronger, etc. They are then all run to get a spectrum of possible solutions. So, one solution could be a storm that completely misses OTS, while another one cuts through the lakes. The mean averages all of these solutions together. So, when you're looking at this map, realize that it is averaging the snowfall from 21 different members, some of which miss completely, while most are various blends of what we have already seen today. Therefore, some members are much higher with the totals, while others are much lower. However, seeing as though the mean continues to get larger, it's indicative of growing confidence in a significant East Coast storm.

2. That is an analog model which is simply done by contours. So the 12" mark simply denotes all areas within it are 12" or greater (likely in the 12-18" range).

3. Yes. It's a scale that was developed by Kocin and Uccellini, in order to assess the impact of any particular event. It's weighted by both population density and spatial coverage of the amount of snow over that population density. A NESIS 5 is essentially the "worst of the worst", or in our case, "best of the best". It means a crap-ton of snow over a very large piece of real estate.

Does that help?

rb924119 wrote:

jmanley32 wrote:

rb924119 wrote:18z Ensemble MEAN:

Why are these amounts so much lower, is this high for this map? Also the one with the white why is it only showing 12 inches, or is the white area highest impact area?  Sorry one more thing do not understand NESIS 5 is that like saying a category 5 hurricane but in snow impact? I know not in winds but man I cannot get over how high there are modeled and consistently, I love that people are actually talking about it, usually I mention winds and everyone says it wont happen lol.

1. They're lower because it's an ensemble mean. The GFS ensemble has 21 separate members, each of which is identical to the Op but run with a single slight change to the initial conditions. For example, one member has a slight faster 200mb jet, another has the 500mb energy stronger, etc. They are then all run to get a spectrum of possible solutions. So, one solution could be a storm that completely misses OTS, while another one cuts through the lakes. The mean averages all of these solutions together. So, when you're looking at this map, realize that it is averaging the snowfall from 21 different members, some of which miss completely, while most are various blends of what we have already seen today. Therefore, some members are much higher with the totals, while others are much lower. However, seeing as though the mean continues to get larger, it's indicative of growing confidence in a significant East Coast storm.

2. That is an analog model which is simply done by contours. So the 12" mark simply denotes all areas within it are 12" or greater (likely in the 12-18" range).

3. Yes. It's a scale that was developed by Kocin and Uccellini, in order to assess the impact of any particular event. It's weighted by both population density and spatial coverage of the amount of snow over that population density. A NESIS 5 is essentially the "worst of the worst", or in our case, "best of the best". It means a crap-ton of snow over a very large piece of real estate.

Does that help?

Also why higher amounts to the south, higher confidence and less divergence and pretty good agreement on lots of snow for the Apps in S-PA and NOVA. Tracks diverge after that and were in more of the battleground further east on whether it continues north or goes more east or northeast.

chief7 wrote:RB I'm assuming that's not good for the coastal sections

That will depend, to be honest. The further north it comes, speaking about the entire system and not just the surface, the less the coastal sections get in on the CCB (cold conveyor banding), which is typically responsible for the largest totals. The reason being that those dynamics are only found on the western and northwestern sides of the mid-level closed circulation, and roughly 200 miles or so away from the center. THAT SAID, with a further north track and/or tighter to the coast, coastal sections will absolutely, undoubtedly, cash in on very impressive WAA (warm air advection), or overrunning snows before any changeover might occur. So, in reality, you will see the same types of snowfall rates as those under the other dynamics, but yours will come sooner than those waiting for the other. Make sense?

rb924119 wrote:

jmanley32 wrote:

rb924119 wrote:18z Ensemble MEAN:

Why are these amounts so much lower, is this high for this map? Also the one with the white why is it only showing 12 inches, or is the white area highest impact area?  Sorry one more thing do not understand NESIS 5 is that like saying a category 5 hurricane but in snow impact? I know not in winds but man I cannot get over how high there are modeled and consistently, I love that people are actually talking about it, usually I mention winds and everyone says it wont happen lol.

1. They're lower because it's an ensemble mean. The GFS ensemble has 21 separate members, each of which is identical to the Op but run with a single slight change to the initial conditions. For example, one member has a slight faster 200mb jet, another has the 500mb energy stronger, etc. They are then all run to get a spectrum of possible solutions. So, one solution could be a storm that completely misses OTS, while another one cuts through the lakes. The mean averages all of these solutions together. So, when you're looking at this map, realize that it is averaging the snowfall from 21 different members, some of which miss completely, while most are various blends of what we have already seen today. Therefore, some members are much higher with the totals, while others are much lower. However, seeing as though the mean continues to get larger, it's indicative of growing confidence in a significant East Coast storm.

2. That is an analog model which is simply done by contours. So the 12" mark simply denotes all areas within it are 12" or greater (likely in the 12-18" range).

3. Yes. It's a scale that was developed by Kocin and Uccellini, in order to assess the impact of any particular event. It's weighted by both population density and spatial coverage of the amount of snow over that population density. A NESIS 5 is essentially the "worst of the worst", or in our case, "best of the best". It means a crap-ton of snow over a very large piece of real estate.

Does that help?

totally thx

NjWeatherGuy wrote:

Also why higher amounts to the south, higher confidence and less divergence and pretty good agreement on lots of snow for the Apps in S-PA and NOVA. Tracks diverge after that and were in more of the battleground further east on whether it continues north or goes more east or northeast.

The higher amounts are due to a few things, some of which you mentioned:

1. Higher confidence and agreement amongst ensemble members
2. Enhanced orographic ascent caused by strong easterlies upsloping over the N-S oriented Appalachian Mountains
3. Model consensus that H5 will be rapidly maturing over the area just southeast of there, which maximizes all possible forcings; low-, mid- and upper-level

As you alluded in your question, there is still disagreement as to when exactly the mid-levels start reaching maturity. If you look at the 18z GFS Op, you will see that it doesn't reach maturity until it is near the Delmarva, which is why the extreme totals expanded northeastward. This is, and has consistently been supported by the CMC for several successive runs now, and there is definitely support amongst its own ensemble that cannot be ignored for a later maturation. That said, because there is still uncertainty, along with the other factors, the ensemble mean begins to decline. I would expect to continue to see it increase northeastward with future runs, assuming status-quo. Does that make a little more sense?

And sroc said he isn't jumping board till Tuesday and he still keeping to his word. Good bless him.

jake732 wrote:And sroc said he isn't jumping board till Tuesday and he still keeping to his word. Good bless him.

he really is very patient

RB and NJ!!! That was one of the best explanations of the amounts being so different I've ever read. Clear and well done.

Thank you RB