December 29th System

[moneypitmike]

Enjoy the snow in Jackson.  It truly is a remarkably marginal situation for your latitude. I could see 5" or 1". It all comes down to dynamics, but I think you'll get 2-3 at least.

 

Thanks.  I'm not sure what the NAM's up to though.  Those are some hefty snow rates for a bunch of us--Chris, Pete, Mitch, Dave, Lurker.

 

Maybe a big surprise in store---or just being set up for a fall.

[moneypitmike]

MPM is really riding the line...seems high bust potential for area out by savoy ...

 

route 9 Vermont....woodford state park....mount snow look to get just crushing blow on nam.....close to a foot there....right over to say Crotched Mtn up to pat's peak/warner/Sunapee  1-1.50 qpf ....btv wrf has similar amount with a similar DUAL QPF jackpot....signaling sick banding somewhere in SVT over to monads/or S lakes region NH.

 

ORH looks isothermal around 9pm with 925's crashing and 850's holding line.....the 925's crash around 495 area wonder if it's cat paws and paste bombs for an hour or two around Marlboro/Harvard/Littleton.

 

That margin of wrong (read: all rain) on the NAM is much lower out here than it had been.  The NAM had been the coldest solution (I think), but it seems doubly so now.

[N. OF PIKE]

Scott, I honestly think it time to chuck em for elevation in CNE.  looking at radar, PWAT's and when I say radar (the sheer breadth of precip) I think there could be areas well over an inch in qpf....maybe more toward 1.25 or so. 

 

BTV WRF has shown this (so it's not just the nam) and the BTV is not showing it do to "weening out on orographics" it has some sick banding in CNE this evening.

 

I would think elevation where that banding takes place from either  S-C VT thru S-C NH - C NH can get a  foot esp AOA 1500 in S VT and 1K or so  in CNH. I could see some 10 inch amounts in lower elevations in New Hampshire as well if banding performs as modeled.

 

Sunapee Snow Storm incoming.....

[PWMan]

Woke up to the dreaded "little or no accumulation" in my updated forecast. Still under a WWA, but it looks like I may be on the wrong side of the razor's edge for this one. I'll be checking in on the status of the backdoor front over the course of the day, as a few miles would make a big difference.

[CT Rain]

Thanks.  I'm not sure what the NAM's up to though.  Those are some hefty snow rates for a bunch of us--Chris, Pete, Mitch, Dave, Lurker.

 

Maybe a big surprise in store---or just being set up for a fall.

 

It closes off the 700/850mb lows in the perfect location for you guys - that would be great for you up through S VT. 

[Damage In Tolland]

Nam might even give a coating down here as it ends. I'd toss it

[CT Rain]

Nam might even give a coating down here as it ends. I'd toss it

 

Looks like you dry slot

[moneypitmike]

The 850 crashes through NW Mass between 00z and 03z--probalby closer to 00 based on the 03 location.  With the slower system, it has over .75" after 00z, so I'm seeing a fair amount of white in this run.  What am I missing?

[dryslot]

Should be some great snowfall rates in this one

[CT Rain]

The 850 crashes through between 00z and 03z--probalby closer to 00 based on the 03 location.  Over .75" after 00z, so I'm seeing a fair amount of white in this run.  What am I missing?

 

Not missing anything - NAM is just a bit more dynamic and therefore a bit cooler. Would be a good hit for you and a great hit up in S VT. 

[SJonesWX]

nothing but rain at home in arlington, but looks like CON is right on the line on this one. Dads not expecting more than a couple inches up that way, but a twist and a turn and that area sees 6". will be interesting to watch.

[moneypitmike]

Not missing anything - NAM is just a bit more dynamic and therefore a bit cooler. Would be a good hit for you and a great hit up in S VT. 

 

Well, let's hope it's right.  Like Messenger said, it's still 10 hours outside its useful range.....

[CoastalWx]

Scott, I honestly think it time to chuck em for elevation in CNE.  looking at radar, PWAT's and when I say radar (the sheer breadth of precip) I think there could be areas well over an inch in qpf....maybe more toward 1.25 or so. 

 

BTV WRF has shown this (so it's not just the nam) and the BTV is not showing it do to "weening out on orographics" it has some sick banding in CNE this evening.

 

I would think elevation where that banding takes place from either  S-C VT thru S-C NH - C NH can get a  foot esp AOA 1500 in S VT and 1K or so  in CNH. I could see some 10 inch amounts in lower elevations in New Hampshire as well if banding performs as modeled.

 

Sunapee Snow Storm incoming.....

 Srn stream juicy systems. Moisture never an issue. I just looked at the NAM...it does have a sick band from MPM to CNH. That's a 6 hr pounding for those areas..especially CNH. It even is a bit unstable. Screw elevation if that happens. Won't need it. It's also pulling in colder air up by Dendrite.  

[CT Rain]

Well, let's hope it's right.  Like Messenger said, it's still 10 hours outside its useful range.....

 

It's really, really borderline. TBH, the NAM doesn't look that crazy - it's definitely within the realm of possibility. 

[CoastalWx]

Usually the euro is decent at sniffing out dynamic systems, but it is still fairly mild. It's possible this storm might be more of a NAM storm because dynamics are needed to flip cooler and the NAM resolution is good for that. Tough call and this will bust one way or the other.

[CoastalWx]

Dendrite to Conway and points east will probably be the winners.

[N. OF PIKE]

 Srn stream juicy systems. Moisture never an issue. I just looked at the NAM...it does have a sick band from MPM to CNH. That's a 6 hr pounding for those areas..especially CNH. It even is a bit unstable. Screw elevation if that happens. Won't need it. It's also pulling in colder air up by Dentrite.

Ya I'm going up to N CON or Cornish (Maine) this pm with the GF. I'm trying to prod her to move it quickly, she wants to stop in Newington to return some xmas gift and I'm thinking we don't want to be driving in that banding over CNE later.

 

I'm thinkin if we leave Newington by 3-4 we should stay ahead of it for most part....

[MarkO]

Scott, I honestly think it time to chuck em for elevation in CNE.  looking at radar, PWAT's and when I say radar (the sheer breadth of precip) I think there could be areas well over an inch in qpf....maybe more toward 1.25 or so. 

 

BTV WRF has shown this (so it's not just the nam) and the BTV is not showing it do to "weening out on orographics" it has some sick banding in CNE this evening.

 

I would think elevation where that banding takes place from either  S-C VT thru S-C NH - C NH can get a  foot esp AOA 1500 in S VT and 1K or so  in CNH. I could see some 10 inch amounts in lower elevations in New Hampshire as well if banding performs as modeled.

 

Sunapee Snow Storm incoming.....

 

Nice, I'm heading up to the cabin this afternoon. If they get 10", they'll re-open Campton Mountain and I will save $200 not taking the kids to a major mountain.

[heavy_wx]

Usually the euro is decent at sniffing out dynamic systems, but it is still fairly mild. It's possible this storm might be more of a NAM storm because dynamics are needed to flip cooler and the NAM resolution is good for that. Tough call and this will bust one way or the other.

 

The 12z NAM analysis for CWMW in southern QB has 250 mb winds around 150 kts. This is a bit closer to the observed sounding than the 00z Euro or the 06z GFS which were about 5 kts weaker. This might suggest the NAM could have a better handle on the strength of the entrance region circulation.

[wxmanmitch]

Anxiously awaiting what happens here IMBY as we're walking a very fine line with regards to precip type. I'm thinking dynamics may win out and we get a parachute snow bomb going here by 21z with at least an advisory level snowfall (3-5") before it ends around 03z near PSF, with perhaps a warning level snowfall at 2K in the central and northern Berkshires. This is a top-down cooling event where dynamic and wet bulb cooling will work its magic.

 

I'm tempted to believe BOX's map is way too low for the east slope of the Berkshires, as I think MPM and MRG get 4-6". My thinking is more in line with ALY's except with some 6-9" totals at 2K. The lower elevations of the southern Berkshires won't do as well with 1-3". The Hudson Valley and greater Albany will probably be 2-4", Pioneer Valley will likely be 1-2" near Springfield and 2-4" near Greenfield. Interesting to note the disagreement between ALY and BOX this morning as their maps often coincide.

[ORH_wxman]

This could be the type of situation where a narrow stripe could get 6-10" and outside of that its 2-3" of slop as dynamics will play a big role until you are pretty far north and northeast into ME and the Whites of NH. OBviously some elevation dependence too.

 

Radar looks pretty healthy, so perhaps its a wider area...but sometimes these marginal events can be funky.

[ineedsnow]

I wonder if this will be one of those times where I get an inch or two and Springfield gets nothing happens on average about once a year my area is kind of a weenie spot around here even driving from one side of town to the other makes a big difference sometimes

Anxiously awaiting what happens here IMBY as we're walking a very fine line with regards to precip type. I'm thinking dynamics may win out and we get a parachute snow bomb going here by 21z with at least an advisory level snowfall (3-5") before it ends around 03z near PSF, with perhaps a warning level snowfall at 2K in the central and northern Berkshires. This is a top-down cooling event where dynamic and wet bulb cooling will work its magic.

 

I'm tempted to believe BOX's map is way too low for the east slope of the Berkshires, as I think MPM and MRG get 4-6". My thinking is more in line with ALY's except with some 6-9" totals at 2K. The lower elevations of the southern Berkshires won't do as well with 1-3". The Hudson Valley and greater Albany will probably be 2-4", Pioneer Valley will likely be 1-2" near Springfield and 2-4" near Greenfield. Interesting to note the disagreement between ALY and BOX this morning as their maps often coincide.

[HIPPYVALLEY]

Anxiously awaiting what happens here IMBY as we're walking a very fine line with regards to precip type. I'm thinking dynamics may win out and we get a parachute snow bomb going here by 21z with at least an advisory level snowfall (3-5") before it ends around 03z near PSF, with perhaps a warning level snowfall at 2K in the central and northern Berkshires. This is a top-down cooling event where dynamic and wet bulb cooling will work its magic.

 

I'm tempted to believe BOX's map is way too low for the east slope of the Berkshires, as I think MPM and MRG get 4-6". My thinking is more in line with ALY's except with some 6-9" totals at 2K. The lower elevations of the southern Berkshires won't do as well with 1-3". The Hudson Valley and greater Albany will probably be 2-4", Pioneer Valley will likely be 1-2" near Springfield and 2-4" near Greenfield. Interesting to note the disagreement between ALY and BOX this morning as their maps often coincide.

 

Your forecast has my full approval!

 

 

30F here atm.

[dendrite]

Still only 28F. Should be a quick, but potent, thump.

[DomNH]

Even here we're just about riding the isothermal 0C line from 850mb down after 3z on the NAM. Close call.

[wxmanmitch]

I wonder if this will be one of those times where I get an inch or two and Springfield gets nothing happens on average about once a year my area is kind of a weenie spot around here even driving from one side of town to the other makes a big difference sometimes

 

Could be, this storm will depend on elevation and dynamics.

 

Definitely some low level cold here sticking around from last night's radiational cooling.

[moneypitmike]

Usually the euro is decent at sniffing out dynamic systems, but it is still fairly mild. It's possible this storm might be more of a NAM storm because dynamics are needed to flip cooler and the NAM resolution is good for that. Tough call and this will bust one way or the other.

 

For BOX office, the bust can only be in one direction.

 

Anxiously awaiting what happens here IMBY as we're walking a very fine line with regards to precip type. I'm thinking dynamics may win out and we get a parachute snow bomb going here by 21z with at least an advisory level snowfall (3-5") before it ends around 03z near PSF, with perhaps a warning level snowfall at 2K in the central and northern Berkshires. This is a top-down cooling event where dynamic and wet bulb cooling will work its magic.

 

I'm tempted to believe BOX's map is way too low for the east slope of the Berkshires, as I think MPM and MRG get 4-6". My thinking is more in line with ALY's except with some 6-9" totals at 2K. The lower elevations of the southern Berkshires won't do as well with 1-3". The Hudson Valley and greater Albany will probably be 2-4", Pioneer Valley will likely be 1-2" near Springfield and 2-4" near Greenfield. Interesting to note the disagreement between ALY and BOX this morning as their maps often coincide.

 

BOX's AFD speaks clearly that this is a real borderline deal.  Ultimately, they opted to take a stance in their forecast and go rain rather than straddle and go in between.  They might be right--at this juncture, I think they may be off.

 

In the meantime, there are some ugly looking temps making their way in that will need to be battled back.

 

33.8/27

[HIPPYVALLEY]

That's some heavy precip over State College area right now.

[ORH_wxman]

925mb temps are a furnace currently still all the way into NNE...so its probably going to start as rain initially as it takes time to wetbulb.

[moneypitmike]

BOX is now going with up to 3" in my p/c.

 

Interesting (and contradictory) statements from their revised AFD:

 

Selective editing:

 

10 AM UPDATE... 03Z SREF AND 12Z NAM SUPPORT PREVIOUS FORECAST AND HEADLINES. THUS NO MAJOR CHANGES EXPECTED. HERE IS AN UPDATE TO THE FOLLOWING STORM ATTRIBUTES...

 

 

then later:

 

WINTRY PRECIP...MAY ISSUE A WINTER WEATHER ADVISORY OR SPECIAL WEATHER STATEMENT FOR NORTHWEST MA AND SOUTHWEST NH FOR A WINTRY MIX OF PRECIP. TWO CONCERNS HERE...TEMPS CURRENTLY IN THE U20S ACROSS THIS REGION. THIS SHALLOW COLD AIR MAY NOT SCOUR OUT YIELDING POTENTIAL FOR FREEZING RAIN. THEN LATER TODAY AND THIS EVENING COLUMN BEGINS TO COOL IN RESPONSE TO HEIGHT FALLS. COOLING PROCESS IS SLOW AS PHASING OF COLDER NORTHERN STREAM IS DELAYED UNTIL STORM PASSES OUR REGION. SO MOST LIKELY SCENARIO IS FOR POTENTIAL OF FREEZING RAIN AT THE ONSET ACROSS THIS REGION...THEN TO ALL RAIN AND ENDING AS A PERIOD OF BRIEF HEAVY WET SNOW AND SLEET. WILL CONTINUE TO EVALUATE OBSERVATIONAL AND MODEL TRENDS.