nzucker Posted November 24, 2014 Share Posted November 24, 2014 looking at the text output from the European model, it looks as though about an inch of precipitation falls at BDLwith the 850 temps below - 2 with surface temps around 33 degrees. personally I would argue that with those rates we would probably drop down to freezing or slightly below. 850 then spikes all the way to + 7 with surface temps rising to about 34 before temperatures crash down into the upper twenties with some backlash precipitation. based on that data here in this neck of the woods I would probably go with a four to eight or five to nine thump with a flip to rain followed by a backlash changeover with an additional inch or two with falling temps. of course if the storm track continues west things could change. Models rarely see the potential for dynamic cooling under heavy precipitation/omega..you'd probably flash to 32/32 with heavy snow considering that profile. You tend to get a tall isothermal column in these conditions. See NYC in the November 2012 storm; no one thought the City could get to 32F but they did because of upward vertical motion/dynamic cooling. Link to comment Share on other sites More sharing options...
CoastalWx Posted November 24, 2014 Share Posted November 24, 2014 In a utopian weather forum this would be a reality. Unfortunately we still sometimes discuss the NAM/SREFs past 36-48hr out of shear boredom as we wait for the varsity models to get on the field. Well doesn't help when forecasters are using them as a blend at hr 84. Link to comment Share on other sites More sharing options...
J Paul Gordon Posted November 24, 2014 Share Posted November 24, 2014 NWS has changed forecast here for Wed-Wed night to mention heavy snow. Night time temp around 30F, but up around 37 during Wednesday daytime. Are they expecting temps to drop as the precip increases? Link to comment Share on other sites More sharing options...
CoastalWx Posted November 24, 2014 Share Posted November 24, 2014 Models rarely see the potential for dynamic cooling under heavy precipitation/omega..you'd probably flash to 32/32 with heavy snow considering that profile. You tend to get a tall isothermal column in these conditions. See NYC in the November 2012 storm; no one thought the City could get to 32F but they did because of upward vertical motion/dynamic cooling. Yep. Usually when models show all snow and 33-35F, it's a 32F snow. Link to comment Share on other sites More sharing options...
TalcottWx Posted November 24, 2014 Share Posted November 24, 2014 didn't you just do that?I guessed between bm and cape, favoring ack track. That's not so definite lol Link to comment Share on other sites More sharing options...
HIPPYVALLEY Posted November 24, 2014 Share Posted November 24, 2014 looking at the text output from the European model, it looks as though about an inch of precipitation falls at BDLwith the 850 temps below - 2 with surface temps around 33 degrees. personally I would argue that with those rates we would probably drop down to freezing or slightly below. 850 then spikes all the way to + 7 with surface temps rising to about 34 before temperatures crash down into the upper twenties with some backlash precipitation. based on that data here in this neck of the woods I would probably go with a four to eight or five to nine thump with a flip to rain followed by a backlash changeover with an additional inch or two with falling temps. of course if the storm track continues west things could change. We know this rarely works out though. Avoid disappointment and never rely on much accumulation from the ever elusive backlash snows. edit: I like your optimism on totals but I'm not even counting on that much up here. Link to comment Share on other sites More sharing options...
CT Valley Snowman Posted November 24, 2014 Share Posted November 24, 2014 I can see how with a more progressive system the moisture could surge ahead of the low and the majority of precipitation could fall before the warm intrusion is completely effective as great lift dynamics upward vertical motion and dynamic cooling are battling the warm air intrusion. but of course if the track was even further west the warm air would push in even faster. Link to comment Share on other sites More sharing options...
nzucker Posted November 24, 2014 Share Posted November 24, 2014 We know this rarely works out though. Avoid disappointment and never rely on much accumulation from the ever elusive backlash snows. It's hard for areas that downslope on NW winds to get significant backlash snows. Link to comment Share on other sites More sharing options...
CT Valley Snowman Posted November 24, 2014 Share Posted November 24, 2014 I wouldn't consider 1 to 2 inches of backlash snow that significant in the storm of the magnitude portrayed by the European , Link to comment Share on other sites More sharing options...
HIPPYVALLEY Posted November 24, 2014 Share Posted November 24, 2014 It's hard for areas that downslope on NW winds to get significant backlash snows. Yeah, I've been in W MA for 7 years and can't remember an event that delivered more than just flurries as the storm departed and temps cooled. Living in Boston there were occasional flips back to snow but I think of it as more frequent occurrence up in the mountains of NNE. Link to comment Share on other sites More sharing options...
HIPPYVALLEY Posted November 24, 2014 Share Posted November 24, 2014 I wouldn't consider 1 to 2 inches of backlash snow that significant in the storm of the magnitude portrayed by the European , It's potent but will be hauling a$$ so it would have to flip back and thump pretty good. Let's just hope the Euro is done trending and we can both look forward to a good front end plastering before the taint. I just don't want to wake up to read that the Euro is taking the surface low over Worcester. lol Link to comment Share on other sites More sharing options...
moneypitmike Posted November 24, 2014 Share Posted November 24, 2014 I wouldn't consider 1 to 2 inches of backlash snow that significant in the storm of the magnitude portrayed by the European , Yeah, I've been in W MA for 7 years and can't remember an event that delivered more than just flurries as the storm departed and temps cooled. Living in Boston there were occasional flips back to snow but I think of it as more frequent occurrence up in the mountains of NNE. I'm with Chris on this one. Snows on the backside are lovely things to see in the forecast. Rarely does it amount to more than a few flurries. Curious as to why they insist on putting that in the forecasts. I do think the qpf may be overdone due to the quickness of the system. Either that or what does come down--be it rn/ip/sn-- will be pretty heavy. I wonder if there will be any agreement amongst the models tonight. I'll see in the morning....bed time. Link to comment Share on other sites More sharing options...
nzucker Posted November 24, 2014 Share Posted November 24, 2014 Yeah, I've been in W MA for 7 years and can't remember an event that delivered more than just flurries as the storm departed and temps cooled. Living in Boston there were occasional flips back to snow but I think of it as more frequent occurrence up in the mountains of NNE. What did you get in XMAS 2002? How about the Feb 26 2010 Snowicane? Did you change back to snow on that one as it pulled out? Link to comment Share on other sites More sharing options...
CT Valley Snowman Posted November 24, 2014 Share Posted November 24, 2014 We know this rarely works out though. Avoid disappointment and never rely on much accumulation from the ever elusive backlash snows edit: I like your optimism on totals but I'm not even counting on that much up here. you must think that the European is not done shifting west. projecting 4-8 or 5-9 is very realistic when the model output is giving 1 inch of precipitation with 850 temperatures below - 2. A straight 10-1 approach would give you 10 inches but I am bumping down because of initial melting and the tendency of models to overdue QPF. Link to comment Share on other sites More sharing options...
moneypitmike Posted November 24, 2014 Share Posted November 24, 2014 What did you get in XMAS 2002? How about the Feb 26 2010 Snowicane? Did you change back to snow on that one as it pulled out? Nate--there are many instances where that happens. But the lion's share of the time, it's bupkis. Link to comment Share on other sites More sharing options...
moneypitmike Posted November 24, 2014 Share Posted November 24, 2014 you must think that the European is not done shifting west. projecting 4-8 or 5-9 is very realistic when the model output is giving 1 inch of precipitation with 850 temperatures below - 2. A straight 10-1 approach would give you 10 inches but I am bumping down because of initial melting and the tendency of models to overdue QPF. I think the EC (and the rest of the models) can continue west. I sure hope it doesn't and ticks back to last night's 00z run. We'll know soon enough. Link to comment Share on other sites More sharing options...
dryslot Posted November 24, 2014 Share Posted November 24, 2014 Yeah, I've been in W MA for 7 years and can't remember an event that delivered more than just flurries as the storm departed and temps cooled. Living in Boston there were occasional flips back to snow but I think of it as more frequent occurrence up in the mountains of NNE. Like never here, Once the winds back NW, We start to clear out, Done Link to comment Share on other sites More sharing options...
CT Valley Snowman Posted November 24, 2014 Share Posted November 24, 2014 Through hour 60, the nam looks west of its previous run. as usual, very late to the party and can always bail out on you at any time. Link to comment Share on other sites More sharing options...
HoarfrostHubb Posted November 24, 2014 Share Posted November 24, 2014 Bruce Schwoegler was big into backlash. How did that work out for him? Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted November 24, 2014 Share Posted November 24, 2014 Like never here, Once the winds back NW, We start to clear out, Done Def not here on the cp. I think that can happen in the higher terrain... Link to comment Share on other sites More sharing options...
SR Airglow Posted November 24, 2014 Share Posted November 24, 2014 Through hour 60, the nam looks west of its previous run. as usual, very late to the party and can always bail out on you at any time. It looked east to me through 72. Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted November 24, 2014 Share Posted November 24, 2014 Bruce Schwoegler was big into backlash. How did that work out for him? Beat me to it That phantom 1-3"...bi*ch owes me like 8' Link to comment Share on other sites More sharing options...
MJO812 Posted November 24, 2014 Share Posted November 24, 2014 Nam ends up way east of the benchmark. Nothing really for SNE northward. Link to comment Share on other sites More sharing options...
Bostonseminole Posted November 24, 2014 Share Posted November 24, 2014 NAM looks east... Link to comment Share on other sites More sharing options...
ineedsnow Posted November 24, 2014 Share Posted November 24, 2014 Nam is refusing to give up on being east. Link to comment Share on other sites More sharing options...
SR Airglow Posted November 24, 2014 Share Posted November 24, 2014 It doesn't do any sort of phasing really, the lead wave escapes east too quickly and as a result it's a weak system, all snow for whoever gets it, but not a lot of QPF to go around. It's the LR NAM though, so I wouldn't put much stock into it's no phasing solution unless other guidance trends in that direction. Link to comment Share on other sites More sharing options...
dryslot Posted November 24, 2014 Share Posted November 24, 2014 Cirrus, Junk Link to comment Share on other sites More sharing options...
The 4 Seasons Posted November 24, 2014 Share Posted November 24, 2014 NAM is east, surprised... thought it was at least nudge west or take a rather large jump but no. Interesting betting the 12Z run does it, but who knows anymore. Link to comment Share on other sites More sharing options...
dryslot Posted November 24, 2014 Share Posted November 24, 2014 Def not here on the cp. I think that can happen in the higher terrain... Definitely, Happens all the time here in the foothills and mountains Link to comment Share on other sites More sharing options...
TauntonBlizzard2013 Posted November 24, 2014 Share Posted November 24, 2014 The Nam is east and pretty meh overall. Interesting though if nothing else, especially for folks grasping at straws for a movement east. Link to comment Share on other sites More sharing options...
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