Weekend Snowfest/Rainfest/Mixed Mess?

[showmethesnow]

Separate thread to discuss the potential weekend storm.

 

Please, Please, Please keep the discussion on target with a minimum of whining, IMBY and generally off topic and/or irrelevant comments. 

[showmethesnow]

For those curious here is the means from the EPS for the weekend storm.

 

[CAPE]

6z GFS a touch warmer, esp at 850 mb. Looks like the high is a bit further east. Timing is critical with this event as the flow is progressive, and the cold is exiting. Not really anything to lock it in.

[showmethesnow]

4 minutes ago, C.A.P.E. said:

6z GFS a touch warmer, esp at 850 mb. Looks like the high is a bit further east. Timing is critical with this event as the flow is progressive, and the cold it exiting. Not really anything to lock it in.

That was my biggest concern yesterday when the GFS/GEFS come in much more progressive with the high. I know it was still working out (snowfall) on the runs but it was very close to crapping the bed.

On a positive note though. The overnight EPS actually looks as if it improved somewhat in that regards. Kind of intrigued with some of the minor changes I am seeing with the EPS (positive changes). 

[CAPE]

2 minutes ago, showmethesnow said:

That was my biggest concern yesterday when the GFS/GEFS come in much more progressive with the high. I know it was still working out (snowfall) on the runs but it was very close to crapping the bed.

On a positive note though. The overnight EPS actually looks as if it improved somewhat in that regards. Kind of intrigued with some of the minor changes I am seeing with the EPS (positive changes). 

Agreed. I am hugging the Euro/EPS for now. The overall setup for this event is precarious, so this could easily trend the wrong way over the next day or so. Pretty much all we have for now, other than tracking how warm it will get the next couple days, and early next week, lol. Would be a huge win to squeeze in a decent snow event, especially given how things have gone so far this month.

[PDIII]

6z is close to a really good event. Looks like low pressure develops off the coast.  Hopefully that keeps the column cold enough for snow. As long as we can stay away from some amped western track solution, I think we have a good shot with this one. Euro and Canadian like high end advisory event.

[Scraff]

Good morning all! Just waking up to check out the overnight runs. I know it’s the 0z CMC, but this would sure be a nice win. I won’t hold my breath...yet.

[showmethesnow]

Saw some improvements in regards to this weekend from the EPS.

Below we have yesterdays 00Z EPS run at 500mb just before the storm impacts the area. 3 things to notice here. First off we have a shortwave rotating around the PV in central Canada. Notice the position (upstate NY) and the lack of reflection of this feature (very weak almost indiscernible). Next,ridging off the coast exists but it is very weak. These first two features are having an impact on the height lines running through our region (Circled). Now lets compare this map to the one below it.

 

This is the overnight run of the EPS. Notice we now see the shortwave farther to the west (midwest) and though weak it does show a much better reflection then the previous map. Next we look at the ridging running up the coast. Though I wouldn't call it strong by any means it is still much better then the previous example. Now look at the impact we see with the height lines through our region. Notice that they have taken on more of a more south/north orientation compared to yesterdays. Now why these height lines are important is because it helps set the track for the storm to follow. Another benefit is that the more south/north orientation allows the storm more room to intensify. 

 

This is yesterdays surface means. We have the low situated off of OBX and it tracks quickly OTS. High pressure is to our NE and we have a CAD signature running down east of the mountains.

 

 

Now look at the changes with see just with a minimal adjustment with those height lines. We see low pressure just off of OBX but now we see it tracking not OTS but more so up the coast to SE of Cape Cod and it has a slower progression (slower progression is also a function of the changes we have seen at 500 mb). The low is also showing a better increase in intensity as well. One other feature of note is that the High to our NE is coming in stronger which is driving the colder air a little farther south as well as helping to produce a stronger CAD signature. These are all good things for our chances of snow through our region.

 

Below we have yesterdays temp map leading into the storm.

 

Now compare the above to the most recent with a stronger High to our north. The zero line has shifted south somewhat (25-35 miles). This may not seem like a big deal but it is. Chances are pretty strong that this will be a marginal temp situation for the cities and S/E and every little bit could mean the difference between rain/snow.

 

 

Now going by the setup show on the EPS I would probably be rooting for 2 things to occur on future runs. A deeper digging, more pronounced shortwave to our west. And a slightly slower progression of the High to our north. We see these two things happen and I think our chances improve quite a bit for a warning criteria event.

[showmethesnow]

37 minutes ago, PDIII said:

6z is close to a really good event. Looks like low pressure develops off the coast.  Hopefully that keeps the column cold enough for snow. As long as we can stay away from some amped western track solution, I think we have a good shot with this one. Euro and Canadian like high end advisory event.

Actually didn't like what I saw with the 06Z GFS. Everything I listed above (about the EPS) about what I would like to see it did the complete opposite. Not as deep of a shortwave. Weaker ridging in front. High retreating a touch quicker. More progressive low. Don't get me wrong, what it does show would work but it would favor southern portions of the region and I think it would be a struggle to get within sniffing distance of a warning criteria snow. eta: (It is also probably a safer bet considering we could have temps issues)

We are getting into the range where the ops need to be taken more seriously but I have never been a big fan of the off runs of the GFS so I am taking what it shows with a grain of salt. I probably favor the Euro op over the GFS anyway until we get within 24-48 hours and then I will hug the one that shows the most snow for me. 

[CAPE]

@showmethesnow

Nice post on the EPS and agree. Overall a better H5 look on the 0z run up top-  the PV is in a better position, slightly stronger ridging over GL, and a better defined 50-50 low. Its really not a bad set up. Need this to not be a blip or noise though. If it holds that look or improves a bit, at least a portion of our region just might get a nice event.

[Thanatos_I_Am]

6z GEFS for those curious.

[pasnownut]

30 minutes ago, showmethesnow said:

Actually didn't like what I saw with the 06Z GFS. Everything I listed above (about the EPS) about what I would like to see it did the complete opposite. Not as deep of a shortwave. Weaker ridging in front. High retreating a touch quicker. More progressive low. Don't get me wrong, what it does show would work but it would favor southern portions of the region and I think it would be a struggle to get within sniffing distance of a warning criteria snow. eta: (It is also probably a safer bet considering we could have temps issues)

We are getting into the range where the ops need to be taken more seriously but I have never been a big fan of the off runs of the GFS so I am taking what it shows with a grain of salt. I probably favor the Euro op over the GFS anyway until we get within 24-48 hours and then I will hug the one that shows the most snow for me. 

Great post man, and I agree with you on the off hour runs.  I know I'll get roasted to some degree, but just so you know...you're not alone.  :).

Pretty cool to be "sneakin one in" in the middle of this mess were in.  Keep it up.  This one is your storm.

[showmethesnow]

7 minutes ago, C.A.P.E. said:

@showmethesnow

Nice post on the EPS and agree. Overall a better H5 look on the 0z run up top-  the PV is in a better position, slightly stronger ridging over GL, and a better defined 50-50 low. Its really not a bad set up. Need this to not be a blip or noise though. If it holds that look or improves a bit, at least a portion of our region might just get a nice event.

I like the look the EPS is moving towards (stronger low, running more so up the coast) but the only problem is that it is a higher risk setup especially for those south and east of the cities. There is some good upside potential here but also major Fail potential if it over amps and trashes the mid levels. So do you roll the dice and go for the jackpot (6-12 inch) or do you play it safe and stick with a much surer thing (1-3,2-4)

If I lived to the S/E of the cities I would probably be rooting for the weak progressive look because it is a much safer bet for them. But N/W of the cities I would be rolling the dice. 

[CAPE]

5 minutes ago, showmethesnow said:

I like the look the EPS is moving towards (stronger low, running more so up the coast) but the only problem is that it is a higher risk setup especially for those south and east of the cities. There is some good upside potential here but also major Fail potential if it over amps and trashes the mid levels. So do you roll the dice and go for the jackpot (6-12 inch) or do you play it safe and stick with a much surer thing (1-3,2-4)

If I lived to the S/E of the cities I would probably be rooting for the weak progressive look because it is a much safer bet for them. But N/W of the cities I would be rolling the dice. 

Well since I can/will travel, I want a bigger event... as long as we aren't talking NE PA or NE lol. Prefer to stay in this region.

[SnowGoose69]

The NAM still wants no part of this which is definitely interesting 

[MD Snow]

32 minutes ago, Thanatos_I_Am said:

6z GEFS for those curious.

Encouraging that there are 5 solutions with the higher axis of snow to our south. 

[showmethesnow]

8 minutes ago, C.A.P.E. said:

Well since I can/will travel, I want a bigger event... as long as we aren't talking NE PA or NE lol. Prefer to stay in this region.

If we continue to see the improvements like the EPS shows I might actually be close to ground zero for the general region (within an hour or two drive) while I am staying at Valley forge. Would expect/hope that the heaviest snows show up just N/W of Philly and progress NEastward as the low amps up. If the models continue to move in that direction you might want to consider a trip up to Valley Forge casino.  Gamble and play in the snow. What more could you ask for.  

[SnowGolfBro]

I’ll take a mini precip bomb over the progressive solution any day and deal with the mixing issues that might come with that. If we get .25 qpf it’s tough to get rates that accumulate.

[BristowWx]

1 minute ago, showmethesnow said:

If we continue to see the improvements like the EPS shows I might actually be close to ground zero for the general region (within an hour or two drive) while I am staying at Valley forge. Would expect/hope that the heaviest snows show up just N/W of Philly and progress NEastward as the low amps up. If the models continue to move in that direction you might want to consider a trip up to Valley Forge casino.  Gamble and play in the snow. What more could you ask for.  

Yes considering you are way north I would expect you to do better in this set up as you keep your 850s.  NW of Philly looks like a money location for this event.  Good birthday present for you but less than good for many others.  I am not of the mind to go against the GFS regardless of the CMC.    

[showmethesnow]

17 minutes ago, BristowWx said:

Yes considering you are way north I would expect you to do better in this set up as you keep your 850s.  NW of Philly looks like a money location for this event.  Good birthday present for you but less than good for many others.  I am not of the mind to go against the GFS regardless of the CMC.    

Actually I would think the chances were good for those west of Balt/DC (maybe the cities themselves) to see a substantial snowfall if the we saw the changes needed in regards to the EPS. Just think that SE PA and NEastward, where temps cooperate, would do better as they would have a longer feed from the CCB. 

As far as which op I would pick (GFS, CMC) at 3 1/2 day leads? I think I would go with the Euro. 

[MD Snow]

6z NAVGEM is way west...It doesn't have any support. I'm hoping its off it's rocker. Worth noting though.

 

6z NAM/ICON/GFS all seemed a bit flatter and less amped overall. 

[Chris78]

26 minutes ago, MD Snow said:

6z NAVGEM is way west...It doesn't have any support. I'm hoping its off it's rocker. Worth noting though.

 

6z NAM/ICON/GFS all seemed a bit flatter and less amped overall. 

That's surprising about the navgem. Its usually the most progressive 

[Ralph Wiggum]

That's surprising about the navgem. Its usually the most progressive 

It is has been progressive and leaning towards more of a fropa. What u r starting to see is more focus on the LP north of the GL with an attached cold front draped across the region.

 

Could we get overunning along the draped cold fropa? Sure. Could a wave develop in the Tenn Valley then off the coast? Sure. Could this turn into just another progressive fropa? Sure. Not exactly sure what to think at this point. There is still some varying clusters on guidance. 12z might help clear things up but probably not.

 

 

[BristowWx]

1 hour ago, showmethesnow said:

Actually I would think the chances were good for those west of Balt/DC (maybe the cities themselves) to see a substantial snowfall if the we saw the changes needed in regards to the EPS. Just think that SE PA and NEastward, where temps cooperate, would do better as they would have a longer feed from the CCB. 

As far as which op I would pick (GFS, CMC) at 3 1/2 day leads? I think I would go with the Euro. 

Agree I suppose.  Still lean on GFS.  Either way you won’t care about anything once the fever takes hold and you get a bonus except where is the waitress with your drink.  NAVGEM gives pause.  NAM does too.  Not sold on anything yet

[Interstate]

19 minutes ago, BristowWx said:

Agree I suppose.  Still lean on GFS.  Either way you won’t care about anything once the fever takes hold and you get a bonus except where is the waitress with your drink.  NAVGEM gives pause.  NAM does too.  Not sold on anything yet

Let's wait on the NAM... there already some changes on the 12z

 

Edit... so the NAM is back with a good thumping.

[NorthArlington101]

8 minutes ago, Interstate said:

Let's wait on the NAM... there already some changes on the 12z

 

Edit... so the NAM is back with a good thumping.

Yeah, NAM looks good. Looks like we start to lose the midlevels though.

[high risk]

NAM looks good, although the low level flow veers around to southeast way too quickly.     Huge differences between the accumulated snow and positive snow change maps, suggesting that the generous accum map is tainted by combining snow and sleet (or it could partially be that the model doesn't want to accumulate snow on somewhat warm ground).

[SnowGolfBro]

The ground shouldn't be too warm.  Friday night looks to dip into the mid 20 range.  Nice to have the NAM showing signs of life.

[yoda]

20 minutes ago, high risk said:

NAM looks good, although the low level flow veers around to southeast way too quickly.     Huge differences between the accumulated snow and positive snow change maps, suggesting that the generous accum map is tainted by combining snow and sleet (or it could partially be that the model doesn't want to accumulate snow on somewhat warm ground).

Could be one of those storms where its like 5 inches on grass... 1-2 inches on roads... IF that happens

[high risk]

2 minutes ago, yoda said:

Could be one of those storms where its like 5 inches on grass... 1-2 inches on roads... IF that happens

      That's certainly possible.   I suspect that sleet explains much of the difference between the NAM snow accum and positive snow depth;  I'm just too lazy to track it down...