Do We have one More in Us?

[Clinch Leatherwood]

Taunton updated and is still going pretty aggressive.  

 

.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY/...
HIGHLIGHTS...

* POTENTIAL BLIZZARD WITH DAMAGING WINDS POSSIBLE FOR CAPE/ISLANDS
* GUSTS OF 55-65 MPH W/LOW PROB UP TO HURRICANE FORCE CAPE/ACK
* SHARP CUTOFF IN SIGNIFICANT SNOWFALL EXPECTED NEAR I-95 CORRIDOR
* LITTLE TO NO IMPACT ACROSS INTERIOR SOUTHERN NEW ENGLAND

 

THIS MAY BE A VERY SERIOUS STORM FOR THE CAPE AND ISLANDS WITH
DAMAGING WINDS ALONG WITH HEAVY SNOW/BLIZZARD CONDITIONS.  THE ONE
THING WE REALLY WANT EMPHASIZE IS THE POTENTIAL FOR THESE STRONG AND
DAMAGING WINDS.  TREMENDOUS PRESSURE GRADIENT WITH LOW PRESSURE NEAR
955 MB EAST OF THE BENCHMARK AND AND A 1030 MB HIGH PRESSURE SYSTEM.
WE EXPECT WIND GUSTS OF 55 TO 65 MPH...BUT A LOW PROBABILITY FOR A
FEW GUSTS TO HURRICANE FORCE ACROSS THE OUTER-CAPE/NANTUCKET.  THIS
MAY RESULT IN DOWNED TREES AND POWER OUTAGES ALONG WITH NEAR ZERO
VISIBILITY IN HEAVY SNOW ALONG WITH SOME BLOWING AND DRIFTING. WILL
CONTINUE BLIZZARD WATCHES FOR 5 TO 10 INCHES OF SNOW IN THIS REGION
WITH A LOW PROBABILITY FOR A FOOT OF SNOW.  DECIDED NOT TO UPGRADE
TO BLIZZARD WARNINGS YET...SINCE ITS LATE 3RD AND 4TH PERIOD.  THE
GFS MODEL IS STILL NOT ONBOARD WITH THE ECMWF...KEEPING THE HEAVIEST
SNOW OUT OVER THE OCEAN SO DON/T WANT TO LOCK US INTO SOMETHING
GIVEN MODEL UNCERTAINTY.

 

[Damage In Tolland]

Euro Ens mean QPF looks pretty reaosnable. I'd probably shave down the western part and tighten the gradient.

1.0" QPF to ACK... 0.5" EWB to PYM... 0.1" DXR to ORE.

I'd probably go coating-1" most of CT and central/western Mass... 1"-3" GON to PVD to 128 corridor... 3-6" PYM to EWB through the Cape. maybe a small sliver of 6+ east of HYA and for ACK.

1-3 to NY border with up to 4 in e ct. Won't be surprised at continued west shift like we saw all day with another 30-50 miles.. Harvey is the best for a reason

[CT Rain]

1-3 to NY border with up to 4 in e ct. Won't be surprised at continued west shift like we saw all day with another 30-50 miles.. Harvey is the best for a reason

 

What does Harvey have? 

[CoastalWx]

What does Harvey have? 

 

1-3 for most of CT IIRC.

[Damage In Tolland]

What does Harvey have?

the map someone posted was 1-3 to NY border and 2-5 eastern 2 counties

[ineedsnow]

Going to chatam after work tomorrow should be awesome

[CT Rain]

1-3 for most of CT IIRC.

 

Just saw his map. Not unreasonable. I'd take the under though on it. 

[CT Rain]

the map someone posted was 1-3 to NY border and 2-5 eastern 2 counties

 

I'm sure he put about 0 thought into the forecast west of ORH or for RI/CT. 

[Damage In Tolland]

I'm sure he put about 0 thought into the forecast west of ORH or for RI/CT.

Maybe but when you post a map on air and on Twitter for other reagions do you just throw some numbers on it or do you have a good handle on it?

[CT Rain]

Maybe but when you post a map on air and on Twitter for other reagions do you just throw some numbers on it or do you have a good handle on it?

 

Depends. I tend to just focus on my viewing area. 

[Damage In Tolland]

Depends. I tend to just focus on my viewing area.

Well I don't think any met on air is going to just guess and throw numbers up without thinking about it

[HIPPYVALLEY]

Depends. I tend to just focus on my viewing area.

Yeah, believe me, nothing exists W of ORH to Boston mets.

[Clinch Leatherwood]

I'm betting this isn't how it's going to play out with dual 968 mb centers...note the temps.

 

I think by the time they get sub 970 we'll have a more consolidated center. This fight that is ongoing over which one is dominant.....   go back and look at last nights 6z RGEM at the point the low is developing off NC vs todays 18z.

 

I think the leftie wins sooner.

 

 

[TalcottWx]

I'm betting this isn't how it's going to play out with dual 968 mb centers...note the temps.

 

I think by the time they get sub 970 we'll have a more consolidated center. This fight that is ongoing over which one is dominant.....   go back and look at last nights 6z RGEM at the point the low is developing off NC vs todays 18z.

 

I think the leftie wins sooner.

Double warm core seclusion? Has that been seen before? Look for the warmest core and I bet thats where the LP will be.

[Clinch Leatherwood]

Double warm core seclusion? Has that been seen before? Look for the warmest core and I bet thats where the LP will be.

 

I can never recall an instance with it happening.

 

I think these runs tonight will move towards one center more sharply.  I can't see there being two as some of the models have at that strength late in the picture.  My only concern would be a situation where even with a very strong development off NC it could still pinwheel on a less than favorable track.

 

I don't know, just looks to me like the stuff way offshore has been too much of an influence on the overall development aloft 36-48 and that maybe the NW solutions are fine - and then we have to worry about the fact that it's going to be a 950mb low and models probably aren't going to be far enough NW with the best banding.

 

We'll see soon, may be totally wrong. 

[Jim Marusak]

I know this set of maps is a bit more of a focus on the Canadian Maritimes than New England per se, and it may be a bit early to call by most standards, but here's what I am thinking for New England and the Maritimes, p-type outlook first then the snowfall outlook, given the consistency attm. Yea there still could be a westwards jog affecting Boston and Providence more, but my main area of concern is from down-east Maine into Nova Scotia and southern New Brunswick. and when looking at the grid numbers, especially in New Brunswick, the Yarmouth/Kenebascis Valley/Minas shore areas of Nova Scotia, I wouldn't rule out 15-1 or so snow ratios over there, given how vertical this system is looking in Nova Scotia. And this is leaning a lot more on a GFS/GEM consensus than the NAM, which hints at 3-4 feet near Moncton NB, Amherst NS, Greenwood NS, and even Charlottetown PEI.

 

p-type outlook

 

 

first call on the snowfall

 

 

(map edited)

[wxsniss]

I'm betting this isn't how it's going to play out with dual 968 mb centers...note the temps.

 

I think by the time they get sub 970 we'll have a more consolidated center. This fight that is ongoing over which one is dominant.....   go back and look at last nights 6z RGEM at the point the low is developing off NC vs todays 18z.

 

I think the leftie wins sooner.

 

I'm guessing you mean Rightie.

Leftie (ie. closer to coast) never wins on guidance... if it did, we'd have ourselves a massive blizzard for larger area.

 

Been harping the timing of this West/Leftie --> East/Rightie low transfer / consolidation for a while. You can see on hi-res models today that it's trending later, suggesting:

a) the vorticity generated way out east may have been overplayed by the models

and/or

b.) the "hangback" energy diving into PA - Delmarva may be underplayed

 

The later this transfer / consolidation, obviously the bigger impact.

You can also appreciate this with the abrupt gap in QPF extending from Delmarva, which slowly is filling in northward as West/Rightie lasts longer.

 

The critical timing for factor "a" is shown on the 18z models between 30-36hrs... ie., Tuesday night. Convection and h5 on RAP will absolutely be fascinating to watch during this.

[TauntonBlizzard2013]

[quome=wxsniss" post="2905430" timestamp="1395708438]

I'm guessing you mean Rightie.

Leftie (ie. closer to coast) never wins on guidance... if it did, we'd have ourselves a massive blizzard for larger area.

Been harping the timing of this West/Rightie --> East/Leftie low transfer / consolidation for a while. You can see on hi-res models today that it's trending later, suggesting:

a) the vorticity generated way out east may have been overplayed by the models

and/or

b.) the "hangback" energy diving into PA - Delmarva may be underplayed

The later this transfer / consolidation, obviously the bigger impact.

You can also appreciate this with the abrupt gap in QPF extending from Delmarva, which slowly is filling in northward as West/Rightie lasts longer.

The critical timing for factor "a" is shown on the 18z models between 30-36hrs... ie., Tuesday night. Convection and h5 on RAP will absolutely be fascinating to watch during this.

Great analysis today. Thanks for that. If I'm understanding you correctly, however long the western low hangs on the better for us. Possible we won't really know until now cast time? Seems like even an hour or two could have Big implications

[Clinch Leatherwood]

I'm guessing you mean Rightie.

Leftie (ie. closer to coast) never wins on guidance... if it did, we'd have ourselves a massive blizzard for larger area.

 

Been harping the timing of this West/Rightie --> East/Leftie low transfer / consolidation for a while. You can see on hi-res models today that it's trending later, suggesting:

a) the vorticity generated way out east may have been overplayed by the models

and/or

b.) the "hangback" energy diving into PA - Delmarva may be underplayed

 

The later this transfer / consolidation, obviously the bigger impact.

You can also appreciate this with the abrupt gap in QPF extending from Delmarva, which slowly is filling in northward as West/Rightie lasts longer.

 

The critical timing for factor "a" is shown on the 18z models between 30-36hrs... ie., Tuesday night. Convection and h5 on RAP will absolutely be fascinating to watch during this.

Actually I did mean the left center. As in getting fired sooner and stronger which by default will mean offshore is weaker and more apt to be pulled into the developing low faster. That won't mean a huge blizzard for everyone, it'll just mean a potentially more uniform trajectory to the precip. On the map I posted we would have a more consolidated low by that panel just a smidge wsw of the northern center. Because of how it all comes together we are still limited in the western extent IMO.

Everything coming together 3-5 hours sooner will mean it's further wsw as it bombs. If I had to lean I think it would be we see the rgem/ggem/gfs come west tonight to a point. No comment on the nam until we see some 0z ua. It does look dubious at 0z

[Tyngsboro Chowdacane]

So many people have thrown in the towel inland. I haven't yet. At leat minute move west is unlikely, but absolutey possible. The Euro held today and was outlier, but getting more support with NAM, RPM, RGEM. It's possible, not likely, but possible, the Euro moves 50 miles west tonight. Then it's so close you have to worry about models not handleing in the banding and west OPF enough. Whether it happens or not , it will be cool to watch unfold over the next 24 hours. And then, damn what a cool storm to watch in the Atlantic.

[wxsniss]

Actually I did mean the left center. As in getting fired sooner and stronger which by default will mean offshore is weaker and more apt to be pulled into the developing low faster. That won't mean a huge blizzard for everyone, it'll just mean a potentially more uniform trajectory to the precip. On the map I posted we would have a more consolidated low by that panel just a smidge wsw of the northern center. Because of how it all comes together we are still limited in the western extent IMO.

Everything coming together 3-5 hours sooner will mean it's further wsw as it bombs. If I had to lean I think it would be we see the rgem/ggem/gfs come west tonight to a point. No comment on the nam until we see some 0z ua. It does look dubious at 0z

 

I guess I see it differently...

 

The West / Leftie center closer to the coast never really wins or dominates on guidance. The West/Leftie center gets fujiwara'ed / sucked into the more dominant East / Rightie center. If it persisted, the West / Leftie low center tracking NNE would have a much much bigger impact on SNE.

 

Track the RGEMs today... you'll see the dual centers persist longer and longer, ie. the West / Leftie center holds its own before getting pivoted away... for example, the West / Leftie center lasts ~6 hours longer on 12z vs. 0z, and this has a critical role in that run being more impactful.

 

I agree with you that if the West / Leftie center develops sooner, it may have a better chance of deepening and persisting longer before the East / Rightie center swings it away.

[Clinch Leatherwood]

[quome=wxsniss" post="2905430" timestamp="1395708438]

I'm guessing you mean Rightie.

Leftie (ie. closer to coast) never wins on guidance... if it did, we'd have ourselves a massive blizzard for larger area.

Been harping the timing of this West/Rightie --> East/Leftie low transfer / consolidation for a while. You can see on hi-res models today that it's trending later, suggesting:

a) the vorticity generated way out east may have been overplayed by the models

and/or

b.) the "hangback" energy diving into PA - Delmarva may be underplayed

The later this transfer / consolidation, obviously the bigger impact.

You can also appreciate this with the abrupt gap in QPF extending from Delmarva, which slowly is filling in northward as West/Rightie lasts longer.

The critical timing for factor "a" is shown on the 18z models between 30-36hrs... ie., Tuesday night. Convection and h5 on RAP will absolutely be fascinating to watch during this.

Great analysis today. Thanks for that. If I'm understanding you correctly, however long the western low hangs on the better for us. Possible we won't really know until now cast time? Seems like even an hour or two could have Big implications

We may know tonight. Or at least have a strong lean. Models are too good for a 1/00. Convection has fired in the gulf and that may help the models get a handle on what that first stage does. My guess is we see a push tonight to have the low off nc fire sooner.

Certainly no later that 6/12z I feel we see really better consensus.

[Clinch Leatherwood]

I guess I see it differently...

The West / Leftie center closer to the coast never really wins or dominates on guidance. The West/Leftie center gets fujiwara'ed / sucked into the more dominant East / Rightie center. If it persisted, that low center tracking NNE would have a much much bigger impact on SNE.

Track the RGEMs today... you'll see the dual centers persist longer and longer, ie. the West / Leftie center holds its own before getting pivoted away... for example, the West / Leftie center lasts ~6 hours longer on 12z vs. 0z, and this has a critical role in that run being more impactful.

I agree with you that if the West / Leftie center develops sooner, it may have a better chance of deepening and persisting longer before the East / Rightie center swings it away.

I may be totally wrong on this but I will be surprised if the more dominant center isn't the nc. By default that would mean the eastern one gets pulled up faster and they merge somewhere wsw of the top and wnw of the bottom in my image above. Minor really may allow the heavier stuff to get a little further west but without a huge push west in the overall shield.

Other option is timing is off and the right center gets swung around too late (gefs 12z), or a really dominating bastardiesque left center. Even in that case it still can't get very far west IMO it would just make for a heavy snow from DE/NJ across LI into se ct/ri and ma.

[TauntonBlizzard2013]

Great analysis today. Thanks for that. If I'm understanding you correctly, however long the western low hangs on the better for us. Possible we won't really know until now cast time? Seems like even an hour or two could have Big implications

We may know tonight. Or at least have a strong lean. Models are too good for a 1/00. Convection has fired in the gulf and that may help the models get a handle on what that first stage does. My guess is we see a push tonight to have the low off nc fire sooner.

Certainly no later that 6/12z I feel we see really better consensus.

Yeah I would think 12z we should know one way or the other. I think your in for a nice event IMO. I think my area is really the big question mark. Do we see a couple inches or 6+? Still pretty much up in the air

[dendrite]

Double warm core seclusion? Has that been seen before? Look for the warmest core and I bet thats where the LP will be.

Looks like a classic shapiro-keyser storm with the warm seclusion, t-bone frontal look, and elongated center.

[TalcottWx]

[Clinch Leatherwood]

Looks like a classic shapiro-keyser storm with the warm seclusion, t-bone frontal look, and elongated center.

Usually west east oriented, I'm not sure that's an exact match and am betting it's an artifact of modeling more than what's about to occur

http://www.comet.ucar.edu/class/comap/06_Aug2_1999/docs/phils/slide16.html

[TalcottWx]

Looks like a classic shapiro-keyser storm with the warm seclusion, t-bone frontal look, and elongated center.

This may be in French but it is close graphically 

[JC-CT]

That's interesting but a little deceiving. It is only showing one low at a time when some models had two.

See: GFS 3/26 0z

[butterfish55]

Zut Alhors!!!