JAN 4th Coastal

[Bob Chill]

8 minutes ago, Cobalt said:

Well, not having a high to the North has been the kiss of death for many events, especially when it moves out just as the storm arrives (such as presidents day 2016 storm). Not sure how much of an impact it'll make here.

The kiss of death is usually temp problems and that's nonexistent no matter how you slice it. What a high to the north helps with (other than temps) is moisture transport. NE-E midlevel and surface flow bring in moisture off the Atlantic and transports it well inland (usually). When lift and dynamics approach there is much more moisture available to wring out and it doesn't take much to precipitate. That's one of the reasons we often have precip onset start well in advance of the approaching low center. Another import thing is a hp will slow a storm's forward progress. 

In this case we have none of that so what we are dealing with is a very fast moving storm with dynamics tight to the low pressure center. When the partial and full phase idea first showed up (and when I got a little excited), upper level help was going to make up for not having a good high to the north. Even just a partial phase could have helped moisture transport well west of us. All we have working for us is an unusually strong storm that passes close enough to *maybe* bully some precip into the dry air and drop a little snow on us. 

Cheat sheet:

Pros: no temp worries, strong storm, close enough 

Cons: no phase, limited upper level support from northern stream, no hp where we normally want it, close but still too far east, very fast moving 

[WxUSAF]

5 minutes ago, nj2va said:

Here’s the 18z GFS sounding when precip is overhead DC.  DP is 17 and temp is 22.  The column is saturated through 950.  Question for the experts here — with the DP at 17 but the column saturated down to 950, would this indicate snow reaching the ground?  I would think yes but wanted to throw it out here for discussion.  

 

Yeah, snow is easily reaching the ground.  More disappointing aspect is the sh-tty dendrite growth it looks like.  Kiss the 20:1 fantasies goodbye.  

[attml]

It never ceases to amaze me how often the models tell us we are going to get a certain amount which we believe and wish for right up until we don't get it yet when the models tells we won't get something we all freak out on how close of a miss we are going to have.  If there was one thing that I learned as a snow nut of a kid living in Maryland and into my adulthood it is that storms coming from the south are unpredictable no matter what the models say and when the models are wrong in these cases we often get hammered!  Just putting this up for posterity!

 

[yoda]

Per Boston AFD, looks like they are doing recon flights for the models tonight.

Not that it might matter here, but interesting nonetheless 

[BristowWx]

20 minutes ago, SnowGolfBro said:

I think we are close to winter weather advisory territory.  If we do get .1-.2 qpf and it comes during the Thursday morning rush hour it could create some havoc.  Especially if there is little warning.  I suppose 0z will be a deciding factor for any advisories to be issued.

I really don't think we are close to anything advisory wise D.C. West and NW.  Dry air we discussed.  Then there is the dominant low pressure issue which could steal it from everyone.  They could wait until the Wed afternoon package.  Or evening.  There is plenty of warning.  This is not an ULL that sneaks up on us. All eyes are on this. Just my 2 cents.

[WEATHER53]

First ob, whether it is of importance or not, is precipitation mass along Florida coast has been stationary last 3 hours 

[Cobalt]

2 minutes ago, BristowWx said:

I really don't think we are close to anything advisory wise D.C. West and NW.  Dry air we discussed.  Then there is the dominant low pressure issue which could steal it from everyone.  They could wait until the Wed afternoon package.  Or evening.  There is plenty of warning.  This is not an ULL that sneaks up on us. All eyes are on this. Just my 2 cents.

Yeah, dry air has cut snow totals in half many times. Not saying it will this time, but this isn't an overrunning event where precip has nowhere to go. 

[BristowWx]

4 minutes ago, yoda said:

Per Boston AFD, looks like they are doing recon flights for the models tonight.

Not that it might matter here, but interesting nonetheless 

When they do that, do they feed that data into the models?  Just curious.

[SnowGolfBro]

1 minute ago, BristowWx said:

I really don't think we are close to anything advisory wise D.C. West and NW.  Dry air we discussed.  Then there is the dominant low pressure issue which could steal it from everyone.  They could wait until the Wed afternoon package.  Or evening.  There is plenty of warning.  This is not an ULL that sneaks up on us. All eyes are on this. Just my 2 cents.

I guess I was just thinking if we see another jump west at 0z the forecasters might get a little antsy.  Of course if we see a shift east they can just put up cold and windy as hell for their forecast.

[nj2va]

5 minutes ago, WxUSAF said:

Yeah, snow is easily reaching the ground.  More disappointing aspect is the sh-tty dendrite growth it looks like.  Kiss the 20:1 fantasies goodbye.  

Thanks...and yeah pixie dust flakes with that sounding. Snow growth zone is non existent. 

[csnavywx]

8 minutes ago, WxUSAF said:

Yeah, snow is easily reaching the ground.  More disappointing aspect is the sh-tty dendrite growth it looks like.  Kiss the 20:1 fantasies goodbye.  

Far better than the crappy snow growth we had at the beginning of the Dec 8 storm though, which was dominated by stunted and heavily rimed needles and columns. At least there's a big chunk of the column at or in the -10 to -20C range, which is good enough for plates or stellar plates and less riming.

[BristowWx]

Just now, SnowGolfBro said:

I guess I was just thinking if we see another jump west at 0z the forecasters might get a little antsy.  Of course if we see a shift east they can just put up cold and windy as hell for their forecast.

Right. Obviously they, LWX are not sold on this yet.  But still a little time and it's weather so it can do what it wants. The wild card factor.  Always present and rarely predictable 

[SnowGolfBro]

1 minute ago, BristowWx said:

Right. Obviously they, LWX are not sold on this yet.  But still a little time and it's weather so it can do what it wants. The wild card factor.  Always present and rarely predictable 

This pretty much sums up why I'm here.  Weather is always present and rarely predictable.  And this one is even more fun to track because I'm assuming 0.0 inches of snow so anything more than that is gravy.

[Wonderdog]

1 hour ago, ryanconway63 said:

I thought DT said this storm couldnt happen.....

If you saw his podcast last night, he explained why we were not going to get a snowstorm because of the low pressure was forming in the Bahamas. he was adamant that we needed to low pressure to form near the coast but I don't remember him making an exact forecast on the podcast I think he was just giving us the possibilities.

[Bob Chill]

8 minutes ago, Cobalt said:

Yeah, dry air has cut snow totals in half many times. Not saying it will this time, but this isn't an overrunning event where precip has nowhere to go. 

At least models account for it so the qpf output is an accurate depiction of what happens on the ground with each run. I've seen it work both ways but agree that it's more common to see less than more QPF at verification. One thing that could potentially bump things on the edge is banding. Outer bands can often outproduce model qpf output. This storm has the potential to throw back a decent band somewhere in MD. Could be one of the times where the outer band outproduces with an under performing zone in between. Something like i95 or ROCKVILLE for instance get's 2-3" while Mitch only gets 1". Yea, something like that.  

[WEATHER53]

Model will over dry this Arctic air mass. We are in teens and low twenties right now and a 30.45 barometer. Most times the rh would be around 30% , instead it's ranging 45-55%

[CAPE]

2 hours ago, batmanbrad said:

if the models keep improving like the GFS just did, PhineasC might change his mind and go for Delaware again?

Looks like a pretty good bet lower DE will see 5-6". His criteria to head there was a foot. So since that does not look likely, it is still Oakland.

[Cobalt]

1 minute ago, Bob Chill said:

At least models account for it so the qpf output is an accurate depiction of what happens on the ground with each run. I've seen it work both ways but agree that it's more common to see less than more QPF at verification. One thing that could potentially bump things on the edge is banding. Outer bands can often outproduce model qpf output. This storm has the potential to throw back a decent band somewhere in MD. Could be one of the times where the outer band outproduces with an under performing zone in between. Something like i95 or ROCKVILLE for instance get's 2-3" while Mitch only gets 1". Yea, something like that.  

I was thinking that banding features could probably boom people somewhere in the Delmarva area depending on how far West the precip shield goes. Could happen like you described it.

[Jebman]

3 minutes ago, Bob Chill said:

At least models account for it so the qpf output is an accurate depiction of what happens on the ground with each run. I've seen it work both ways but agree that it's more common to see less than more QPF at verification. One thing that could potentially bump things on the edge is banding. Outer bands can often outproduce model qpf output. This storm has the potential to throw back a decent band somewhere in MD. Could be one of the times where the outer band outproduces with an under performing zone in between. Something like i95 or ROCKVILLE for instance get's 2-3" while Mitch only gets 1". Yea, something like that.  

There you go HoCo and the Chill Deathband. 

These nearly always verify.

[Deck Pic]

Nothing matters for another 6 hours. Enjoy your evenings. 

[Bob Chill]

4 minutes ago, Deck Pic said:

Nothing matters for another 6 hours. Enjoy your evenings. 

The thing that pisses me off about the euro is it walked away from a good event while the gfs is walking towards a good event. GFS never once teased us with a digital bomb and I'm thankful for it. Euro basically served up a steak and lobster and left us with a bowl of free peanuts. The gfs left us hungry the whole time and finally slid a bowl of mac and cheese down the bar. Hopefully @ 0z the gfs tosses in a can of PBR to wash it down. 

[THEREALTOR1]

8 minutes ago, Cobalt said:

I was thinking that banding features could probably boom people somewhere in the Delmarva area depending on how far West the precip shield goes. Could happen like you described it.

somewhere between salisbury and milford will pop with double digits no doubt, has been that way for just about every storm the past 2 years

[WVclimo]

6 minutes ago, losetoa6 said:

I'm pulling for the .1 to HGR

Me too, lol.  

It's early, but the 'easterners' have really taken a nice lead over the I-81 crew in snowfall so far.  I went back and compared MRB seasonal snowfall to BWI to see how common it is for the metro areas to exceed here for a season.  21 times in 92 years BWI has had more, so more common than I would have guessed.  Might be one of those years.

[SnowGoose69]

Just now, Bob Chill said:

The thing that pisses me off about the euro is it walked away from a good event while the gfs is walking towards a good event. GFS never once teased us with a digital bomb and I'm thankful for it. Euro basically served up a steak and lobster and left us with a bowl of free peanuts. The gfs left us hungry the whole time and finally slid a bowl of mac and cheese down the bar. Hopefully @ 0z the gfs tosses in a can of PBR to wash is down. 

The Euro since it’s upgrade 2 times ago ( not the most recent one) has been prone beyond 96 hours to have bombs that end up not verifying.  Inside 72 it’s main problem is it’s a very slow adjuster.  It’s still usually the closest of any other global at 80-90 most of the time so it scores best but I find it’s sometimes catching up to the RGEM and NAM on QPF and other meso features inside 48 

[CAPE]

51 minutes ago, Bob Chill said:

There's actually more spread in the members than I thought. A few whiffs along the corridor but most push at least a trace in. Half get .1 to i95. A couple outliers push .3 to dca. One gets .1 all the way to HGR. Lower resolution and shorter leads don't give much weight to the members but the outliers are notable for the short lead time. 

I mentioned this earlier with the EPS. The member spread, ranging from next to nothing to heavy snow, was notable even towards the coast, where the forecast (and highest probability) is for warning criteria snow. So, still some pretty high uncertainty, which one could interpret (spin) a few different ways- ranging from a decent potential for this to improve (more snow west side of the low), to a pretty high bust potential for the whole MA region, lol.

[Bob Chill]

1 minute ago, SnowGoose69 said:

The Euro since it’s upgrade 2 times ago ( not the most recent one) has been prone beyond 96 hours to have bombs that end up not verifying.  Inside 72 it’s main problem is it’s a very slow adjuster.  It’s still usually the closest of any other global at 80-90 most of the time so it scores best but I find it’s sometimes catching up to the RGEM and NAM on QPF and other meso features inside 48 

Agreed. No op is good with synoptic events beyond 96 hours and are very prone to large swings. Inside of 72 it's typically hard to beat the euro in general but I have seen exactly what you are talking about with slow adjustments. Personally, I think the GFS is much better than people give it credit for. It's a very good model. Prone to busts like any op but some people rag the hell out of it and all that tells me is their bias gets in the way of their ability to properly use the tools provided. We'll see how this storm goes down but it sure seems to me that the GFS has lead the way with consistency. It's been a rock in general while other globals have moved around quite a bit. 

What's up with the NAVGEM? Did they upgrade it or something? It's been a lot better this year than I remember in the past. Maybe it's because I haven't paid much attention but it's certainly not a joke model like it's made out to be. 

[Scarlet Pimpernel]

1 minute ago, Bob Chill said:

The thing that pisses me off about the euro is it walked away from a good event while the gfs is walking towards a good event. GFS never once teased us with a digital bomb and I'm thankful for it. Euro basically served up a steak and lobster and left us with a bowl of free peanuts. The gfs left us hungry the whole time and finally slid a bowl of mac and cheese down the bar. Hopefully @ 0z the gfs tosses in a can of PBR to wash it down. 

Yeah, that kooky run or two of the Euro was interesting while it was there!  And it wasn't for this upcoming event, but the GFS did give us that ridiculous 36-hour (or whatever it was) non-stop snow event for the period right after Christmas in one run!  That's a filet mignon with lobster, with a caviar appetizer and whatever fancy French dessert afterward (plus some Veuve Cliquot champagne to top it off)!

So we're down to mac and cheese now, or perhaps stale bread crumbs!  I'll pass on the PBR, thank you!

Anyhow, on topic, it is true that the GFS never really was overly enthusiastic in this area for the Thursday event.  Maybe a run or two looked kind of good several days back, I can't recall.  But it's been adamant that it won't be much here.  That said, Thursday sure looks like it could be bitter with brisk winds and cold temperatures, regardless of anything else!  More chapped skin, I guess...humidifiers continue to work overtime.

[THEREALTOR1]

7 minutes ago, SnowGoose69 said:

The Euro since it’s upgrade 2 times ago ( not the most recent one) has been prone beyond 96 hours to have bombs that end up not verifying.  Inside 72 it’s main problem is it’s a very slow adjuster.  It’s still usually the closest of any other global at 80-90 most of the time so it scores best but I find it’s sometimes catching up to the RGEM and NAM on QPF and other meso features inside 48 

Not sure when the upgrades took place, but when the euro nailed Sandy from about a week out (eventually the Nam was the next to come around to the final euro solution), I thought I recalled everyone saying the euro was the best at handling these super low pressured storms off coming up the east coast.... has that since changed??

[Cobalt]

2 minutes ago, Bob Chill said:

Agreed. No op is good with synoptic events beyond 96 hours and are very prone to large swings. Inside of 72 it's typically hard to beat the euro in general but I have seen exactly what you are talking about with slow adjustments. Personally, I think the GFS is much better than people give it credit for. It's a very good model. Prone to busts like any op but some people rag the hell out of it and all that tells me is their bias gets in the way of their ability to properly use the tools provided. We'll see how this storm goes down but it sure seems to me that the GFS has lead the way with consistency. It's been a rock in general while other globals have moved around quite a bit. 

What's up with the NAVGEM? Did they upgrade it or something? It's been a lot better this year than I remember in the past. Maybe it's because I haven't paid much attention but it's certainly not a joke model like it's made out to be. 

It's not running right now for 18z for whatever reason, but I agree with you. It's been very consistent, and showed it by leading the way during the Dec 8-9 snow event. 

[SnowGoose69]

11 minutes ago, THEREALTOR1 said:

Not sure when the upgrades took place, but when the euro nailed Sandy from about a week out (eventually the Nam was the next to come around to the final euro solution), I thought I recalled everyone saying the euro was the best at handling these super low pressured storms off coming up the east coast.... has that since changed??

The Euro was upgraded in 2012 I think and January 2016.  Prior to the 2012 upgrade I found it was much better in the 84-108 hour period.  Since that I don’t think it’s as good