December 12, 2017 - Late Bloomer Coastal

[dendrite]

Could be interesting here. If we can slide that sfc low a little south around the wedge we could stay all snow for the meaningful precip. SE NH is looking porked unless we see a more southward shift. The euro kept it below freezing here and only got the freezing line a little north of CON. That’s a typical spot where sfc warmth decides to halt. 

[powderfreak]

Man that is a sweet set-up on the 18z GFS... forget the QPF... give me a vertically stacked cyclonic flow with a low parked just north of FVE and let the mountains do their thing.

Our climo favored position is for stacked cyclones just north or northeast of FVE.  Good cold air advection with excellent snow growth temps near ridgetop elevations on NW flow with saturated atmosphere through 700mb... if this isn't a pants tent, I mean what is? lol.

[powderfreak]

2 minutes ago, dendrite said:

Could be interesting here. If we can slide that sfc low a little south around the wedge we could stay all snow for the meaningful precip. SE NH is looking porked unless we see a more southward shift. The euro kept it below freezing here and only got the freezing line a little north of CON. That’s a typical spot where sfc warmth decides to halt. 

I'm not as well versed in your local climate and exact locations but I've been thinking the Lakes Region looks like a prime spot to get a quick dump of 6"+.  I would assume your area is golden too?  This seems like a good congrats Dendrite type event.

[dryslot]

7 minutes ago, dendrite said:

Could be interesting here. If we can slide that sfc low a little south around the wedge we could stay all snow for the meaningful precip. SE NH is looking porked unless we see a more southward shift. The euro kept it below freezing here and only got the freezing line a little north of CON. That’s a typical spot where sfc warmth decides to halt. 

Little to close to the gradient here for my liking.

[ORH_wxman]

5 minutes ago, dryslot said:

Little to close to the gradient here for my liking.

Still think we might see a southeast tick or at least a delay in how fast the low levels warm...we'll see how well the cold dome is modeled. Of course, there's some other factors too like the two shortwaves that are responsible. 

[dryslot]

4 minutes ago, ORH_wxman said:

Still think we might see a southeast tick or at least a delay in how fast the low levels warm...we'll see how well the cold dome is modeled. Of course, there's some other factors too like the two shortwaves that are responsible. 

Not a fan of the stronger primary tracking further north in this instance.

[powderfreak]

6 minutes ago, ORH_wxman said:

Still think we might see a southeast tick or at least a delay in how fast the low levels warm...we'll see how well the cold dome is modeled. Of course, there's some other factors too like the two shortwaves that are responsible. 

I feel like these always tick colder with a faster secondary development in the final 24 hours.  How many times have we seen that with CAD down to like the ORH Hills and northeast?

[Typhoon Tip]

This storm is like an NFL QB that doesn't know it's time to retire... He still thinks there's a comeback there, yet all his coaches know it's been time, probably for more than one year ... yet, they honor his legacy and no one has the heart to tell him or encourage him to step aside.. 

 

[ORH_wxman]

7 minutes ago, powderfreak said:

I feel like these always tick colder with a faster secondary development in the final 24 hours.  How many times have we seen that with CAD down to like the ORH Hills and northeast?

 Very frequently but it could def still trend worse if that primary gets stronger. Fine line. I could see advisory snows down to ORH region or all the way past CON getting porked if it trend worse. 

[moneypitmike]

I approve of the  Box map.....methinks that will change in the next version.

 https://www.weather.gov/box/winter

 

[powderfreak]

53 minutes ago, Typhoon Tip said:

This storm is like an NFL QB that doesn't know it's time to retire... He still thinks there's a comeback there, yet all his coaches know it's been time, probably for more than one year ... yet, they honor his legacy and no one has the heart to tell him or encourage him to step aside.. 

 

Then he ends up making a playoff run that likely ends in the first round but it's acceptable to the team's fans.  He gave it a good effort and connected on some decent snowfall, err long passes, and shoveled off the haters.

[ORH_wxman]

29 minutes ago, powderfreak said:

Then he ends up making a playoff run that likely ends in the first round but it's acceptable to the team's fans.  He gave it a good effort and connected on some decent snowfall, err long passes, and shoveled off the haters.

There will prob be like one euro run either tonight or tomorrow that looks a lot better and sucks a bunch back in and then it will go back to a meh solution for anyone south of PWM-MHT-PSF line. Then on actual verification day we will be surprised that ORH is still 32 at 18z when models said it would be 41. But the snow will still end up disappointing us in the southern half of this forum. 

[Damage In Tolland]

14 minutes ago, ORH_wxman said:

There will prob be like one euro run either tonight or tomorrow that looks a lot better and sucks a bunch back in and then it will go back to a meh solution for anyone south of PWM-MHT-PSF line. Then on actual verification day we will be surprised that ORH is still 32 at 18z when models said it would be 41. But the snow will still end up disappointing us in the southern half of this forum. 

Just leave us with total snow pack . And not melt it away like a few said today . Please that’s all we ask 

[ORH_wxman]

1 minute ago, Damage In Tolland said:

Just leave us with total snow pack . And not melt it away like a few said today . Please that’s all we ask 

I'd be pretty shocked if you didn't have full coverage after Tuesday. Southeast areas and maybe coastal MA will prob get hit hard enough to open up bare ground in spots. But interior is going to take their time warming the surface up. You really got to get wetbulb over 36-37 to accelerate the melt. 

[snowgeek]

Here’s some of ALB’s thinking for there high totals. GAZPACHO!!!!!

“Recent research here at the office has focused on using our GIS
tool GAZPACHO to offer guidance on QPF biased forecasting in
various flow regimes. For the upcoming storm, we are looking at
925mb winds southeast around 30 knots. Research shows that in
this regime we have typically underestimated snowfall in favored
upslope regions of the Adirondacks and Greens. Putting it all
together we are looking for 8 to 12 inches in the watch area
with amounts trending lower away from watch zones. This would
imply advisory criteria snowfall for much of the remainder of
the area. Across the mid Hudson valley temperatures may warm
enough to bring some rain into the picture holding down totals.
High temperatures will range from mid 20s north to upper 30s
south.”

What’s interesting is that the lower elevations in the HV usually don’t do great with a strong SE low level wind. We usually downslope and warm up. Maybe the 8-12” is in the MV and southern Daks is real, but maybe a steeper gradient to lower totals in the valley might make more sense?


Sent from my iPad using Tapatalk

[metagraphica]

9 minutes ago, ORH_wxman said:

I'd be pretty shocked if you didn't have full coverage after Tuesday. Southeast areas and maybe coastal MA will prob get hit hard enough to open up bare ground in spots. But interior is going to take their time warming the surface up. You really got to get wetbulb over 36-37 to accelerate the melt. 

Even today's full sunshine and 39 degrees did a number on the 2.5" that fell.  But that's par for the course down here.  I expect Tuesday to take away the rest of it.  At least Wed and Thurs will be cold enough to freeze the ground solid.  Mud in December would be even more depressing than frozen brown ground.

[powderfreak]

3 minutes ago, snowgeek said:

Here’s some of ALB’s thinking for there high totals. GAZPACHO!!!!!

“Recent research here at the office has focused on using our GIS
tool GAZPACHO to offer guidance on QPF biased forecasting in
various flow regimes. For the upcoming storm, we are looking at
925mb winds southeast around 30 knots. Research shows that in
this regime we have typically underestimated snowfall in favored
upslope regions of the Adirondacks and Greens. Putting it all
together we are looking for 8 to 12 inches in the watch area
with amounts trending lower away from watch zones. This would
imply advisory criteria snowfall for much of the remainder of
the area. Across the mid Hudson valley temperatures may warm
enough to bring some rain into the picture holding down totals.
High temperatures will range from mid 20s north to upper 30s
south.”

What’s interesting is that the lower elevations in the HV usually don’t do great with a strong SE low level wind. We usually downslope and warm up. Maybe the 8-12” is in the MV and southern Daks is real, but maybe a steeper gradient to lower totals in the valley might make more sense?

That's pretty cool.  I've never heard of that but its true, I think the one area of improvement for Northeast NWS offices would be increased sensitivity to terrain effects with regards to precipitation totals.  I'm not sure how you do that, and while it has come a long way in the past 5-10 years, there is still work to do with regards to precipitation forecasts and orographics. 

I bet they do under-estimate snowfall at times on E/SE flow when the conditions are favorable for a good low-level assist.  Same how up here we can under-estimate the orographics...but you can't just always assume the higher amounts.  That's why a good model or better understanding of the "why" comes into play.  We all know the possibilities with upsloping precipitation, from "go big" to "go home," but its awesome to see more effort put into studying/analyzing that aspect of forecasting.

[AfewUniversesBelowNormal]

RAP is pretty different from 18z models, holding back a lot of energy at 21hr. Looks more organized. 

[mreaves]

1 hour ago, powderfreak said:

Then he ends up making a playoff run that likely ends in the first round but it's acceptable to the team's fans.  He gave it a good effort and connected on some decent snowfall, err long passes, and shoveled off the haters.

Or he somehow gets to the Super Bowl and ruin the other team’s shot at an undefeated season?

[STILL N OF PIKE]

22 minutes ago, mreaves said:

Or he somehow gets to the Super Bowl and ruin the other team’s shot at an undefeated season?

And leads his team to a 2-11season?

[mreaves]

10 minutes ago, STILL N OF PIKE said:

And leads his team to a 2-11season?

It can go either way lol. 

[backedgeapproaching]

31 minutes ago, snowgeek said:

Here’s some of ALB’s thinking for there high totals. GAZPACHO!!!!!

“Recent research here at the office has focused on using our GIS
tool GAZPACHO to offer guidance on QPF biased forecasting in
various flow regimes. For the upcoming storm, we are looking at
925mb winds southeast around 30 knots. Research shows that in
this regime we have typically underestimated snowfall in favored
upslope regions of the Adirondacks and Greens. Putting it all
together we are looking for 8 to 12 inches in the watch area
with amounts trending lower away from watch zones. This would
imply advisory criteria snowfall for much of the remainder of
the area. Across the mid Hudson valley temperatures may warm
enough to bring some rain into the picture holding down totals.
High temperatures will range from mid 20s north to upper 30s
south.”

What’s interesting is that the lower elevations in the HV usually don’t do great with a strong SE low level wind. We usually downslope and warm up. Maybe the 8-12” is in the MV and southern Daks is real, but maybe a steeper gradient to lower totals in the valley might make more sense?


Sent from my iPad using Tapatalk

Yea, it makes sense what ALY is saying and also what you are saying. I kind of mentioned it in the NNE thread, I could see some of the favored east slopes locations doing well.  Following up to what PF said--it be nice to have some detailed orographic forecasts, I know its tough with NWS offices, they kind of have to paint a broad brush sometimes and cant pin point every orographic nuance through the whole service area--Im guessing that takes time and money.

You know your local climo saying you don't do well on SE winds, same here. So, when I see 8-12, I expect lower taking into account local climo biases.  But yea, maybe if there was a way to have a more detailed forecast or mapping tool.  I'm sure if OceanStWx was around he could comment on it.

[powderfreak]

1 hour ago, Damage In Tolland said:

Just leave us with total snow pack . And not melt it away like a few said today . Please that’s all we ask 

I agree with ORH...you'll be fine for snow cover.  Grab an inch or two on the front side and maybe no real loss at all?  

[Go Kart Mozart]

3 hours ago, Typhoon Tip said:

This storm is like an NFL QB that doesn't know it's time to retire... He still thinks there's a comeback there, yet all his coaches know it's been time, probably for more than one year ... yet, they honor his legacy and no one has the heart to tell him or encourage him to step aside.. 

 

Eli

[AfewUniversesBelowNormal]

NAM is still racing the first piece, which may not happen. 

[40/70 Benchmark]

I think my pack will be patchy after Tuesday.

[USCAPEWEATHERAF]

6 minutes ago, StormchaserChuck said:

NAM is still racing the first piece, which may not happen. 

That first piece of energy is almost to the US border with Saskatchewan, Canada

[USCAPEWEATHERAF]

Watch short range models, they are slowing down that lead piece of Pacific jet energy, but the NAM hasn't bitten on this yet.

[40/70 Benchmark]

I wish this event would evaporate....two days of holiday snowpack...then poof.

[AfewUniversesBelowNormal]

this is fun.. small shifts can make a huge difference. 02z RAP is pretty awesome at 21hr
theoretically run it forward and it may bottom at 960smb in Maine.