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Oct 22/23rd Sat /Sun heavy rain, high wind, elevation upslope snow. All of New England

Ginx snewx

By Ginx snewx,
in New England

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CoastalWx

CoastalWx

Posted
Posted
1 minute ago, Typhoon Tip said:

Yes ...as we discussed yesterday, that's aspect of this system evolution stepped down in appeal yesterday.   

The NAM's FRH grid has 25 kts sustained mid-boundary layer over Logan - I've seen stronger for a myriad of different reason and all of those ended up manageable.  

 

I mean they'll be some spots near 50 perhaps. Decent.  I guess maybe give it more respect this time of year with leafed trees.

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Typhoon Tip

Typhoon Tip

Posted
Posted
20 minutes ago, CoastalWx said:

I mean they'll be some spots near 50 perhaps. Decent.  I guess maybe give it more respect this time of year with leafed trees.

Oh...of course! 

There are 'reading' users that will [somehow] comprehend that as 'no wind' - or better yet, only impugn the Meteorologist if it affects "them" (those are truly cherishable types ...) and vote for Trump - that's my troll stroke for the day :)  - But that's not what we're saying either. 

the trouble with wind is that there seems to be a fuzzy area of research on exactly when things get that 'edge'.  Best example I can think of is "Andrew, '92" ... it was intensifying as it made land-fall (clue one), and that is theorized as partial in why it scraped edifices down to slabs in some cases ... but, later it was also evidenced/papered that 'twister clusters" were embedded in the eye-wall, ...basically suction vortices like those pivoting around a mile-wider in the plains, only doing it at the scale of hurricane's inner core.  

The work is out there, it's fascinating.

Anyway, that's an example of knowing a big wind event is coming, but the 'edge' of that disaster was ...not anticipated.  No way. 

Similarly ...tho not similarly (heh), isallobaric wind bombs are not really picked up in NAM FRH grids ..and I'm not sure there are any products in use anyway that try to ferret those sort of rarer circumstantial set-ups.  Science/observational review detects that large fall/rise pressure couplets are involved, and mathematically ... it makes sense when we know that the Coriolis term has a time variable/dependence ...such that the restoring response for big atmospheric ridge-valley scenarios exceeds sub-geostrophic equation of motion and the wind flows straight at the low pressure... with extreme rapidity in some cases.  

Getting the models to see all that ahead ?  I'm not sure I've seen that specific a detail anticipated beyond guess work by the interpreter.  

25 kts with good mixing in CAA will lean trees to 38 mph (probably) which is good, and there will probably be gusts to 50 due to micro/meso scale interactions. 

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CoastalWx

CoastalWx

Posted
Posted
18 minutes ago, Typhoon Tip said:

Oh...of course! 

There are 'reading' users that will [somehow] comprehend that as 'no wind' - or better yet, only impugn the Meteorologist if it affects "them" (those are truly cherishable types ...) and vote for Trump - that's my troll stroke for the day :)  - But that's not what we're saying either. 

the trouble with wind is that there seems to be a fuzzy area of research on exactly when things get that 'edge'.  Best example I can think of is "Andrew, '92" ... it was intensifying as it made land-fall (clue one), and that is theorized as partial in why it scraped edifices down to slabs in some cases ... but, later it was also evidenced/papered that 'twister clusters" were embedded in the eye-wall, ...basically suction vortices like those pivoting around a mile-wider in the plains, only doing it at the scale of hurricane's inner core.  

The work is out there, it's fascinating.

Anyway, that's an example of knowing a big wind event is coming, but the 'edge' of that disaster was ...not anticipated.  No way. 

Similarly ...tho not similarly (heh), isallobaric wind bombs are not really picked up in NAM FRH grids ..and I'm not sure there are any products in use anyway that try to ferret those sort of rarer circumstantial set-ups.  Science/observational review detects that large fall/rise pressure couplets are involved, and mathematically ... it makes sense when we know that the Coriolis term has a time variable/dependence ...such that the restoring response for big atmospheric ridge-valley scenarios exceeds sub-geostrophic equation of motion and the wind flows straight at the low pressure... with extreme rapidity in some cases.  

Getting the models to see all that ahead ?  I'm not sure I've seen that specific a detail anticipated beyond guess work by the interpreter.  

25 kts with good mixing in CAA will lean trees to 38 mph (probably) which is good, and there will probably be gusts to 50 due to micro/meso scale interactions. 

I'm gonna digress Tippy style for a bit, as this reminded me of something I thought about yesterday.

 

  Situational awareness. Yesterday was a good example (at least in my eyes) about how important it is to be aware of the meteorological issues at hand, and how this can really add value over computer models.  Given the forcing at hand, low and mid level convergence and frontogenesis, combined with those PWATs....it's almost a given that 3-4" falls in a short time over a small area. Like, fact.  You don't need some ensemble to tell you there is 2-3SD inflow at 850, 3SD PWATs, 2-3SD V component at 200mb. No need to over-analyze. That had the look of FFW when the meso's were spitting out 2-4" at times in bands. And guess what, the area was much much wider than modeled too.  Same with Matthew over NC. That should be an automatic 12"+ in your eyes when you see those models spit out that QPF. You know that a transitioning storm with developing fronts is going to annihilate a small area. Don't tell me, "well the global models only had 6-8" of rain.." anyone with experience knows that look in NC was a recipe for disaster. The good news is that hi res guidance did a real good job showing the extraordinary amounts of rain.  Take for example winter weather. We know that the 700mb back bent warm front zone is going to destroy a narrow area where it sets up.  We know that the modeled 0.6" QPF in this zone may turn into 12-18" of see-through fluff.  My point to all of this, is that before even looking at model solutions...there is something to be said about situational awareness over verbatim model solutions. In the world of automation...this is an area where the good mets out there have quite the edge still. 

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Ginx snewx

Ginx snewx

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Posted
23 minutes ago, CoastalWx said:

I'm gonna digress Tippy style for a bit, as this reminded me of something I thought about yesterday.

 

  Situational awareness. Yesterday was a good example (at least in my eyes) about how important it is to be aware of the meteorological issues at hand, and how this can really add value over computer models.  Given the forcing at hand, low and mid level convergence and frontogenesis, combined with those PWATs....it's almost a given that 3-4" falls in a short time over a small area. Like, fact.  You don't need some ensemble to tell you there is 2-3SD inflow at 850, 3SD PWATs, 2-3SD V component at 200mb. No need to over-analyze. That had the look of FFW when the meso's were spitting out 2-4" at times in bands. And guess what, the area was much much wider than modeled too.  Same with Matthew over NC. That should be an automatic 12"+ in your eyes when you see those models spit out that QPF. You know that a transitioning storm with developing fronts is going to annihilate a small area. Don't tell me, "well the global models only had 6-8" of rain.." anyone with experience knows that look in NC was a recipe for disaster. The good news is that hi res guidance did a real good job showing the extraordinary amounts of rain.  Take for example winter weather. We know that the 700mb back bent warm front zone is going to destroy a narrow area where it sets up.  We know that the modeled 0.6" QPF in this zone may turn into 12-18" of see-through fluff.  My point to all of this, is that before even looking at model solutions...there is something to be said about situational awareness over verbatim model solutions. In the world of automation...this is an area where the good mets out there have quite the edge still. 

great excellent post.  To recap QPF queens be damned

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Typhoon Tip

Typhoon Tip

Posted
Posted
34 minutes ago, CoastalWx said:

I'm gonna digress Tippy style for a bit, as this reminded me of something I thought about yesterday.

 

  Situational awareness. Yesterday was a good example (at least in my eyes) about how important it is to be aware of the meteorological issues at hand, and how this can really add value over computer models.  Given the forcing at hand, low and mid level convergence and frontogenesis, combined with those PWATs....it's almost a given that 3-4" falls in a short time over a small area. Like, fact.  You don't need some ensemble to tell you there is 2-3SD inflow at 850, 3SD PWATs, 2-3SD V component at 200mb. No need to over-analyze. That had the look of FFW when the meso's were spitting out 2-4" at times in bands. And guess what, the area was much much wider than modeled too.  Same with Matthew over NC. That should be an automatic 12"+ in your eyes when you see those models spit out that QPF. You know that a transitioning storm with developing fronts is going to annihilate a small area. Don't tell me, "well the global models only had 6-8" of rain.." anyone with experience knows that look in NC was a recipe for disaster. The good news is that hi res guidance did a real good job showing the extraordinary amounts of rain.  Take for example winter weather. We know that the 700mb back bent warm front zone is going to destroy a narrow area where it sets up.  We know that the modeled 0.6" QPF in this zone may turn into 12-18" of see-through fluff.  My point to all of this, is that before even looking at model solutions...there is something to be said about situational awareness over verbatim model solutions. In the world of automation...this is an area where the good mets out there have quite the edge still. 

:) ... furthering yet ..  

knowing when/where the 'positive bust' is going to happen, or is likely to - 

Here's another good example.  Two days before the Snow Bomb storm of December 23, 1997, the (then) ETA FOUS product printed out sigma temperature numbers similar to this for Logon:     03 01 97, with total QPF spanning 6 to 12 hours ~ .7" 

The forecast from media and from KTAN seemed to confirm per AFD, 1-3" of wet snow ending as drizzle west of the I-95, cold rain in the city. 

Concept wise the forecast we spot on;  the most snow fell west of I95 - good call! 

Detail-wise, the Devil claimed its due!

What actually happened was a polar high ..not tremendously thick with pressure, but enough so, built across eastern Ontario through northern Maine, and imparted a nosed CAD down just about collocated with the spine of the Whites' toward NYC.  Overnight, the sky coverage was utterly clear, with bone-chilling (relative to machine guidance) radiational cooling HUGELY positively feed-back into the set up.  Meanwhile during the overnight, a moderately potent v-max turned NE out of the OV and started moving normal to said lower tropospheric ridge axis (meaning...straight at it). 

An hour either side of dawn, the cloud shield came in and 'capped' the intensely cooled lower levels, and as a result, event-entrance showed regions temperatures substantially colder than previous guidance. 

This was all anticipated the previous day.  Because the synoptic evolution depicted by the MRF, Euro...ETA all of them, showed that high pressure moving N of our region during the overnight, with the v-max and attended dynamics then moving into the area during the morning.  The rest was history.. 

That 03 = +3 C at 980 mb level; 02 = +2 C at 900 mb level; 98 = -2 C at 800 mb level then becomes interesting... 

That means that what was verifying was something more like 96 97 98, which implies -4, -3, -2 respectively.  That only intensified the frotogenic forcing as the v-max attributed UVM max rode over the top of that under-forecast' cold. The snow growth region of the sounding was then consequentially utterly maximized. 

A large area of intense radar DBZ was witnessed blossoming over LI, amid a general region of light to moderate freezing/frozen. This region intensified further to become truly awesome in size and reflectivity, surpassing many thunderstorm cores one might see in the summer time, spread out over multiple Massachusett's county wide areas.  Snow fall rates exceed 7" per hour in more than one location over much of NE CT, central MA, NW RI and along I-95 up into S NH.  When all was said and down, a top tier snow storm event was logged in history, with totals ranging from 12" to nearly 30", most of which fell in 6 hours!  

We call these positive busts, because ...well, lets call a rose a rose:  it's dystopian lust.  To much of society, that's a crippling scary scenario, to go on with 1-3" of ...even if it was 2-5" forecasts, which imply one thing, and end up with a society-haulter bomb.  Amazing, but ... to Scotts point, some astute observations the day before based upon situational awareness with that high, circumstantial radiative cooling feedback...and not just going with machine guidance was a failing that seemed to pervasive for that particular event.  

 

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J Paul Gordon

J Paul Gordon

Posted
Posted

We're in Maine. Daughter called from West Boylston in a panic about the warnings. She's on the second floor in a well drained area. Rain really starting to come down here in Wells Kennebunk area after ten and poured most of the night. Not sure how much we got. Still drizzling and mild. Nice to see snow shot from WV

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powderfreak

powderfreak

Posted
Posted

First Winter Weather Advisory of the season for the northeast in the Adirondacks. 

INCLUDING THE CITIES OF...STAR LAKE...SARANAC LAKE...
TUPPER LAKE...DANNEMORA...LAKE PLACID
1016 AM EDT SAT OCT 22 2016

...WINTER WEATHER ADVISORY IN EFFECT FROM 6 PM THIS EVENING TO
11 AM EDT SUNDAY...

THE NATIONAL WEATHER SERVICE IN BURLINGTON HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOW ACROSS THE NORTHERN ADIRONDACK REGION OF
NEW YORK...WHICH IS IN EFFECT FROM 6 PM THIS EVENING UNTIL 11 AM
EDT SUNDAY.

* LOCATIONS...NORTHERN ADIRONDACKS OF NEW YORK.

* HAZARD TYPES...WET SNOW.

* ACCUMULATIONS...UP TO 3 TO 5 INCHES OF HEAVY WET SNOW.

* MAXIMUM SNOWFALL RATE...UP TO 1 INCH PER HOUR...MAINLY DURING
  THE OVERNIGHT HOURS.

* TIMING...RAIN WILL GRADUALLY CHANGE TO WET SNOW DURING THE LATE
  AFTERNOON AND EARLY EVENING HOURS. PERIODS OF SNOW WILL CONTINUE
  THROUGH THE OVERNIGHT HOURS, WHICH WILL BE WHEN MOST OF THE SNOW
  ACCUMULATION WILL OCCUR. LINGERING SNOW WILL TAPER OFF TO SNOW
  SHOWERS MID TO LATE SUNDAY MORNING.
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Typhoon Tip

Typhoon Tip

Posted
Posted
2 minutes ago, powderfreak said:

First Winter Weather Advisory of the season for the northeast in the Adirondacks. 


INCLUDING THE CITIES OF...STAR LAKE...SARANAC LAKE...
TUPPER LAKE...DANNEMORA...LAKE PLACID
1016 AM EDT SAT OCT 22 2016

...WINTER WEATHER ADVISORY IN EFFECT FROM 6 PM THIS EVENING TO
11 AM EDT SUNDAY...

THE NATIONAL WEATHER SERVICE IN BURLINGTON HAS ISSUED A WINTER
WEATHER ADVISORY FOR SNOW ACROSS THE NORTHERN ADIRONDACK REGION OF
NEW YORK...WHICH IS IN EFFECT FROM 6 PM THIS EVENING UNTIL 11 AM
EDT SUNDAY.

* LOCATIONS...NORTHERN ADIRONDACKS OF NEW YORK.

* HAZARD TYPES...WET SNOW.

* ACCUMULATIONS...UP TO 3 TO 5 INCHES OF HEAVY WET SNOW.

* MAXIMUM SNOWFALL RATE...UP TO 1 INCH PER HOUR...MAINLY DURING
  THE OVERNIGHT HOURS.

* TIMING...RAIN WILL GRADUALLY CHANGE TO WET SNOW DURING THE LATE
  AFTERNOON AND EARLY EVENING HOURS. PERIODS OF SNOW WILL CONTINUE
  THROUGH THE OVERNIGHT HOURS, WHICH WILL BE WHEN MOST OF THE SNOW
  ACCUMULATION WILL OCCUR. LINGERING SNOW WILL TAPER OFF TO SNOW
  SHOWERS MID TO LATE SUNDAY MORNING.

Intellicast's ptype is popping blues already in mid NYS ... probably 'whitish' rain drops with catspawing

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powderfreak

powderfreak

Posted
Posted

Ginxy, some of the HRRR runs have been insane with the precipitation on the Spine later tonight.

This is what I was talking about yesterday as the overall set-up synoptically for upslope is about as solid as it gets.  Regardless of snowfall it could be quite prolific for a time in terms of QPF.

Latest HRRR has over 2" at Mansfield and Jay Peak through 18 hours...with like 0.7" at MVL.  That's actually a fairly standard gradient and makes sense.

I think Mansfield gets lit up tonight at least at the picnic tables.  Could wake up to like 6" or like 14" if some of these meso-scale models have any say.

hrrr_t_precip_neng_19.png

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powderfreak

powderfreak

Posted
Posted

One cam to watch will be the Sugarbush snow cam at 4,000ft.  They had some big drifting issues last season with this (its literally up top at 4,000ft on the ridge so its nearly impossible to get snow to fall straight down) but looks like they cut back the trees and jammed it a bit further into the dense spruce. 

Its an awesome set-up though if they can figure out the drifting issues. 

http://www.sugarbush.com/mountain/webcams/

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CoastalWx

CoastalWx

Posted
Posted
9 minutes ago, powderfreak said:

Ginxy, some of the HRRR runs have been insane with the precipitation on the Spine later tonight.

This is what I was talking about yesterday as the overall set-up synoptically for upslope is about as solid as it gets.  Regardless of snowfall it could be quite prolific for a time in terms of QPF.

Latest HRRR has over 2" at Mansfield and Jay Peak through 18 hours...with like 0.7" at MVL.  That's actually a fairly standard gradient and makes sense.

I think Mansfield gets lit up tonight at least at the picnic tables.  Could wake up to like 6" or like 14" if some of these meso-scale models have any say.

hrrr_t_precip_neng_19.png

Given the situation, can't really disagree with HRRR.

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powderfreak

powderfreak

Posted
Posted
Just now, CoastalWx said:

Given the situation, can't really disagree with HRRR.

I usually poo-poo those huge amounts on the mesos but I think we've had this discussion in the past...how the early and late season events when there's slightly more moisture available the mountains can pull some surprising QPF amounts from orographics alone.  Its October and April where we can get those 2-3" QPF upslope events just because the atmosphere can hold more water at these marginal temps (I know you know this, just thinking aloud, haha).

Be really interesting to see how this shakes out.  Snow growth though is pretty crappy, as obviously the DGZ is well above the level that the best UVVs will be taking place (below 750mb).  Could see some really dense snow up there.

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Ginx snewx

Ginx snewx

Posted
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Posted
16 minutes ago, powderfreak said:

Ginxy, some of the HRRR runs have been insane with the precipitation on the Spine later tonight.

This is what I was talking about yesterday as the overall set-up synoptically for upslope is about as solid as it gets.  Regardless of snowfall it could be quite prolific for a time in terms of QPF.

Latest HRRR has over 2" at Mansfield and Jay Peak through 18 hours...with like 0.7" at MVL.  That's actually a fairly standard gradient and makes sense.

I think Mansfield gets lit up tonight at least at the picnic tables.  Could wake up to like 6" or like 14" if some of these meso-scale models have any say.

hrrr_t_precip_neng_19.png

14Z HRRR

Untitled.png

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powderfreak

powderfreak

Posted
Posted
3 minutes ago, Ginx snewx said:

HRRR Centered on the 4K Picnic table

 

Yeah the 12z 4km NAM is right there with the HRRR, printing 2.0-2.5" QPF over Mansfield from 21z this afternoon through 21z tomorrow. 

There's certainly some high bust potential here on the summits.  Probably won't make much difference below 2,000ft as I think it struggles mightily below that elevation...but do the Picnic Tables get 5-8" or like 14-16" is now my question.

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