Jump to content
  • Member Statistics

    17,609
    Total Members
    7,904
    Most Online
    NH8550
    Newest Member
    NH8550
    Joined

Potential Major East Coast Storm on Saturday Part 2


IsentropicLift

Recommended Posts

Trend is awful tonight so far, no denying it. 1.23 qpf to .6 for nyc in 1 run. Not to mention the .6 is most likely not all snow. There was talk here earlier of 30 inches of snow....more likely 4 -8/

With all due respect, you should not even be thinking about what QPF is showing this far out. Right now, we should still be concentrating on what the upper levels are doing. The Euro was painfully close to a huge hit for the area, but it didn't resolve the phase. This phase will likely not be resolved until around 36 hours to the event. What we saw tonight was that a huge storm is still on the table, but as always, the devil will be in the details.

United States Coast Guard Rescue Swimmer

Link to comment
Share on other sites

  • Replies 1.2k
  • Created
  • Last Reply

Trend is awful tonight so far, no denying it. 1.23 qpf to .6 for nyc in 1 run. Not to mention the .6 is most likely not all snow.  There was talk here earlier of 30 inches of snow....more likely 4 -8/

 

All Isentropic lift was saying was that 1.5" of LE could translate to 30" in locations that saw intense mesoscale banding, which is probably a bit of an exaggeration, but not outrageously far off. He never "predicted" it, per se, and he should be given a little leeway in saying it at the height of the Eurogasm run this afternoon, which looked so beautiful.  

 

http://www.americanwx.com/bb/index.php/topic/45431-potential-coastal-storm-this-weekend/?p=3274133

 

People jumping ship with multiple models showing good to great tracks is just ridiculous.  Could we have a miss to a near miss and only get a few inches of snow and some slop?  Sure, but with all the players being much better sampled tomorrow, we'll finally get to see where we're headed.  And anyone who understands chaos theory/chaotic systems, like the weather, knows that accurate initial conditions are incredibly important in reducing how quickly the cone of uncertainty on the mean of a model output grows with each time increment forward from those initial conditions, i.e., our cone of uncertainty is pretty damn large right now, but it'll be a lot smaller for the 12Z runs tomorrow, with much better initial conditions and a shorter time to the event.  

Link to comment
Share on other sites

All Isentropic lift was saying was that 1.5" of LE could translate to 30" in locations that saw intense mesoscale banding, which is probably a bit of an exaggeration, but not outrageously far off. He never "predicted" it, per se, and he should be given a little leeway in saying it at the height of the Eurogasm run this afternoon, which looked so beautiful.  

 

http://www.americanwx.com/bb/index.php/topic/45431-potential-coastal-storm-this-weekend/?p=3274133

 

People jumping ship with multiple models showing good to great tracks is just ridiculous.  Could we have a miss to a near miss and only get a few inches of snow and some slop?  Sure, but with all the players being much better sampled tomorrow, we'll finally get to see where we're headed.  And anyone who understands chaos theory/chaotic systems, like the weather, knows that accurate initial conditions are incredibly important in reducing how quickly the cone of uncertainty on the mean of a model output grows with each time increment forward from those initial conditions, i.e., our cone of uncertainty is pretty damn large right now, but it'll be a lot smaller for the 12Z runs tomorrow, with much better initial conditions and a shorter time to the event.  

 

Absolutely...as the amount of time between the onset of any event decreases...the model divergences will diminish...and some consensus should be reached...probably by the 12z runs on Friday.

Link to comment
Share on other sites

After reading the last 5 pages I have come to the conclusion that some  of you are just insane . If someone is on here for a week saying this is OTS and this actually occurs the fact that the system just doesn't phase and close off like it did yesterday at 12z does not mean the poster who said OTS is right .

Look at the SLP reflections is that OTS ?  The Next cluster are at or slightly east of the BM .

 

Only the NAVGEM continues to PHASE. ( That`s the issue , not the SLP placements ) . The UKMET is a good  but does not have the CCB look the 12z Euro had or NAVGEM still have .

Please if you are going to make an argument , make sure you just don`t just make one that is emotional and devoid of the truth . The fact that the 0Z suite is not as enthusiastic about the amount of snow through the area is NOT due to OTS ( The GFS is furthest east , so if that's east 3 days out I am not shocked ) .  The early phasing and rapid closing off that did not take place on most of the globals last nite is the reason the NW side CCB never develops ( AND THAT WAS ALWAYS GOING TO BE KNYCs SAVING GRACE )  .

 

What was written was expect Rain on the coast  , then you CCB on the back as per the 12z Euro  ( There is no longer a 36mb drop in 18 hours at 0z like you saw at 12z  )  So you will not cool the column period  If it that does not  happen and it`s possible it was so over amped then it was just wrong .

But the  talk of OTS was wrong . The bottom line is if you don` t phase early enough or at all you don`t CCB and that`s what some of the models were advertising for the last 2 days .

post-7472-0-57009400-1421918550_thumb.pn

post-7472-0-69393000-1421918578_thumb.pn

Link to comment
Share on other sites

And Warmer!

 

At 66 ?   really , the forecast was  always  rain at KNYC and snow on the backend .

We have been saying the ONLY way to get snow at KNYC is CCB.

 

The fact that it`s not east is 1 thing , the cleaner phase gets you to CCB

 

Even yesterdays 12z euro rained in NYC before we flipped . Every model is warm man . That's not news nor is it what we are looking for .

OTS is not what we are seeing . NOW CAN YOU SHOW ME THE LAST GFS RUN THAT DOES THIS ?

post-7472-0-61124400-1421921251_thumb.pn

Link to comment
Share on other sites

We'll see how the 12z runs trend tomorrow, but this was not a good trend on the 00z suite tonight!

 

This is why it difficult to get excited about all snow here with the AO spiking positive after only a brief dip.

The SE Ridge will be a factor and the coast will have to worry about P-Type issues instead of a pure

snow event on Saturday with such an amplified system. Our best chances for all snow are clippers

in this pattern.

Link to comment
Share on other sites

This is why it difficult to get excited about all snow here with the AO spiking positive after only a brief dip.

The SE Ridge will be a factor and the coast will have to worry about P-Type issues instead of a pure

snow event on Saturday with such an amplified system. Our best chances for all snow are clippers

in this pattern.

Even in the best case yesterdays Euro still rained then we cooled on the back end .

I think we have to rain and sleet from the city east for a while , the question is how fast can we close off ( or at all ) and then have the column collapse . The whole forecast on the coast comes down to do we CCB , if, where and for how long .

The models are still advertising that .

Link to comment
Share on other sites

Even in the best case yesterdays Euro still rained then we cooled on the back end .

 

I think have to rain and sleet from the city east for a while , the question is how fast can we close off ( or at all ) and then have the column collapse . The whole forecast on the coast comes down to do we CCB , if,  where and for how long .

 

The models are still advertising that .

 

I won't really start thinking about amounts until I see what the Friday 12z model suite comes up with. 

But the progressive nature of the pattern makes it harder for the system to close off while still

south of our latitude.

Link to comment
Share on other sites

Anyone else surprised Upton already threw out 6" numbers? They are a finicky bunch. Sometimes they hold back and other times they throw out early numbers.

Sent from my iPhone

they did that on their experimental "MAXIMUM POTENTIAL" map - it's not there forecast - very different mood in here than 18 hours ago  :whistle:  who would have thought the Euro's perfect 12Z solution wouldnt change....gonna be a long couple of days with weenies jumping off bridges

Link to comment
Share on other sites

they did that on their experimental "MAXIMUM POTENTIAL" map - it's not there forecast - very different mood in here than 18 hours ago :whistle: who would have thought the Euro's perfect 12Z solution wouldnt change....gonna be a long couple of days with weenies jumping off bridges

Ah, I missed that. My bad. I should have looked closer.

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

Well the 06z GFS came west a bit and the 0z Euro didn't bomb out early enough...but we still have today and tomorrow to sort things out. I'm not sure what the bridge jumping is for. There is definitely some energy and timing to sort out. The precip shield wants to get sheered on the west side. However, H5 and low track looks pretty good. NYC still goes slop to heavy snow on a CCB. This is a thread the needle to a certain degree. If the storm can close off earlier we are in business. We are still in a good spot IMO..

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

I always love the we have time. As if yesterday's euro was a lock. As bluewave has been saying the SE ridge is a big issue. Just look at last weekends storm you had to be above 3000' in central Vermont for snow in mid January and it wasn't a lakes cutter! There will be precip problems for sure. Remember back to 93-94 and the tons of sleet and freezing rain. This has a similar look just a different reason for being there. When the cold really locks in like monday the coast will see snow. Unfortunately I don't think this is our storm. That doesn't mean we don't get to 6" with tons of taint but big numbers not this time

Link to comment
Share on other sites

I always love the we have time. As if yesterday's euro was a lock. As bluewave has been saying the SE ridge is a big issue. Just look at last weekends storm you had to be above 3000' in central Vermont for snow in mid January and it wasn't a lakes cutter! There will be precip problems for sure. Remember back to 93-94 and the tons of sleet and freezing rain. This has a similar look just a different reason for being there. When the cold really locks in like monday the coast will see snow. Unfortunately I don't think this is our storm. That doesn't mean we don't get to 6" with tons of taint but big numbers not this time

right - someone may see that but I never understood why people were just looking at the euro verbatim and making these huge predictions - a screaming jet, short storm, and a situation where everything needs to go right for the coastal plain - yeah, that should have all been enough to give pause and see how things shake out

Link to comment
Share on other sites

So the eastern tracks look bogus at this time. Most outlets going with a mix for the big cities which seems like a safe bet at this point. Should be far enough west that some nw burbs cash in tho. Unclear how far west this tracks attm. 12z suite should be telling. Last night people were jumping thinking everything was east....I bet people jump at 12z when things go west and show a warm bl. Just a hunch.

Link to comment
Share on other sites

The 00z EPS mean is almost an inch of water at KNYC and the 0.50"+ contour stretches back to the Poconos. In addition, nearly all of the individual members are tightly clustered 50-75 miles SE of ACY and then over the benchmark. Although the intensisty has come down some since the 12z run yesterday, we have very few members that would be indicative of a miss based upon track alone. This includes the control run which tracks from 985mb 50 miles East of VA Beach to 974mb over the benchmark.

 

So then if it's not the track causing the problems then why is the precip shield so poorly developed on the NW side?

 

Let's look at the 500mb vorticy map valid 21z Saturday on the 06z NAM. A few things stand out, and that is the subsidence located over PA and the strong kicker shortwave over Michigan.

 

namconus_z500_vort_neus_22.png

 

Now lets look at yesterday's 12z NAM run valid for the same period. As you can see that subsidence is still there but much further West. Also the kicker over Michigan is much weaker. All in all the polar jet has trended stronger which is limiting the lift NW of the center.

 

namconus_z500_vort_neus_28.png

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...