#PD3Attempt#13since2003 -Tracking the threat of the Presidents day storm Feb 15-16 2016

[Heisy]

UKIE is much improved still tracks inland, but I 'imagine' with this SLP location we'd get some frozen precip to start

 

[Ian]

GEFS members all have a pretty good track too it seems. Maybe 2-4 over land, rest offshore.

[Ji]

Let's see if euro goes east tonight. All east models went west and west models went east

[Ian]

Let's see if euro goes east tonight. All east models went west and west models went east

Euro is on the western envelope so it definitely could. Though it seems like the best solution given the setup.. so.. got me.

[Ji]

GEFS members all have a pretty good track too it seems. Maybe 2-4 over land, rest offshore.

this is your time period. Don't betray yourself

[dan123]

GEFS members all have a pretty good track too it seems. Maybe 2-4 over land, rest offshore.

Odd.

[Ian]

this is your time period. Don't betray yourself

lol I know what's wrong with me.

 

[Ian]

We do get that Davis Strait block for a few days out ahead of it. Maybe that's enough. The heights over Hudson to Greenland and then in the 50/50 region are kinda whacked though during the event. There aren't many big events that look like that. But I suppose it wouldn't be a top event so perhaps that's why. Just seems the look would favor west vs east.

[Deck Pic]

We do get that Davis Strait block for a few days out ahead of it. Maybe that's enough. The heights over Hudson to Greenland and then in the 50/50 region are kinda whacked though during the event. There aren't many big events that look like that. But I suppose it wouldn't be a top event so perhaps that's why. Just seems the look would favor west vs east.

 

The models like to run storms into the gut of cold air masses.  Even the HECS when the pattern was sick we had some runs with the R/S line moving west of town.  We've definitely seen teens and then rain and 47 degrees 24 hours later, but usually in Ninas with lows well west.  My guess is we'll see something half decent on the front end at the very least....

[Deck Pic]

Euro is about 5-6" on the front end for DC...more the further NW you go...surface stays cold...

[MillvilleWx]

Euro is about 5-6" on the front end for DC...more the further NW you go...surface stays cold...

 

Definitely a more pronounced CAD wedge on the Euro. The positioning of the high is offshore, but you could see in the panels leading up to the precip edging in a better signature for surface cold. 

[HighStakes]

I'm behind on maps but it looks like a very nice step in the right direction.

Much nicer solution. More in line of what you would expect with something coming fast on the heels of an extreme cold blast. Snow overspreads the area by early monday morning.

[Deck Pic]

Definitely a more pronounced CAD wedge on the Euro. The positioning of the high is offshore, but you could see in the panels leading up to the precip edging in a better signature for surface cold. 

 

It makes sense that we'd do ok up front given the air mass, strong retreating high, and model biases...hopefully it keeps trending...nice run

 

ETA - this is probably frozen for a lot of people even after mid level temps go up.....surface is pretty cold...

 

[HighStakes]

Definitely a more pronounced CAD wedge on the Euro. The positioning of the high is offshore, but you could see in the panels leading up to the precip edging in a better signature for surface cold. 

Relatively quick mover on the Euro. Gets in here before we lose the cold. Never makes it above freezing N and W. 

[MillvilleWx]

It makes sense that we'd do ok up front given the air mass, strong retreating high, and model biases...hopefully it keeps trending...nice run

 

ETA - this is probably frozen for a lot of people even after mid level temps go up.....surface is pretty cold...

 

Screen Shot 2016-02-11 at 1.27.14 AM.png

 

Yup!! Just took a closer look at the panels and places west of the fall line are really close to or just below zero at 850 with surface actually below freezing the entire event for areas starting NW MoCo riding up Parrs Ridge to NMD and west. The4 temps even in the cities aren't all that bad either. It's close, and def. an improvement for the front end thump idea.

 

Yep. I noticed that. It looks like the system comes in faster too?

We live to fight another day.

 

A little faster yes, which is what we want for the best chance at front end stuff. Try to beat the retreating high as much as possible. The one thing that was interesting with this run was the orientation of the precip shield up the east coast. A little more expansion westward would probably result in the current LP track. It was an absolute paste bomb for Blue Ridge west with 8-12" in the current setup. DC and Baltimore walk on the 3-6" line with gradient NW to SE as usual. Elevation guys of course do well here.

[MillvilleWx]

Relatively quick mover on the Euro. Gets in here before we lose the cold. Never makes it above freezing N and W. 

 

Yeah. That was the one thing I wanted to see on this run is if the signature for CAD was a little more robust. When I saw at 6z Monday the wedge in GA, I had a feeling this run could end up colder with a slightly further east track. 

[Deck Pic]

Yeah. That was the one thing I wanted to see on this run is if the signature for CAD was a little more robust. When I saw at 6z Monday the wedge in GA, I had a feeling this run could end up colder with a slightly further east track. 

 

Here is the surface at onset of snow for DC metro

 

[MillvilleWx]

Here is the surface at onset of snow for DC metro

 

Screen Shot 2016-02-11 at 1.39.01 AM.png

 

Here's the 850 at onset as well. Still pretty cold.

 

[Deck Pic]

Here's the 850 at onset as well. Still pretty cold.

 

850 euro.PNG

 

yeah...we're in really nice shape at the beginning....Will be fun to watch it snow on a holiday....immediate stickage

[MillvilleWx]

6z GFS is a paste bomb for the Blue Ridge on west. Temps struggle to pop above freezing for western Frederick Co. out toward the Allegheny Front. 850's actually stay below freezing for the entire event west of the fall line, but the surface temps become the issue for areas east of that including the cities. The total precip was over an inch for HGR on east, with the 0.5" inch contour west of the mountains. Verbatim, the model still shows a 2-4" storm starting at I95 and with a tight gradient increases to over 10" out in the counties west of the cities. Run was a little closer to the coast looking at surface maps which allowed for a bit more warm air intrusion, but the run wasn't completely horrid and basically stayed the course outside of a wobble to the west. 

[showmethesnow]

00Z Euro ensemble snowfall means is very similar to the last couple of runs with the 2" line running roughly through Balt and DC. The individual members don't look as promising though for the corridor with 30 showing less then 2 inches. There are also roughly 20 members that show that any meaningful snow will be confined to the mountains.

 

The means shows the low running directly over top the cities but the clustering of lows suggest that we could possibly see an adjustment south and east on future runs.  The means at 500 also now has a neutral trough aligned with the Mississippi where as with previous runs we had seen a slightly negative one. If this just isn't noise this would also suggest a possible adjustment south and east on the low.

[Snowman.]

Tight gradient on the 06z GFS

[MacintoshPro]

Just looked at the Euro... It's actually not snow to rain for DC. It would be a little rain but our temperatures don't go above freezing at the surface until the precipitation a pretty much done. It would probably be snow to sleet or ice for us.

[SomeguyfromTakomaPark]

Just looked at the Euro... It's actually not snow to rain for DC. It would be a little rain but our temperatures don't go above freezing at the surface until the precipitation a pretty much done. It would probably be snow to sleet or ice for us.

 

Euro is pretty much the best case scenario for us.  We'd get to watch snow accumulate all day on Monday. According to the Euro we'd have 6 inches but everyone else on the East Coast except Upstate NY and extreme NNE would torch. When's the last time that happened?  Feb 2010?

[mappy]

GFS Cobb output for Westminster for 2/16

 

00z: 1.46 qpf (ends as RASN)

 

06z: 1.19 qpf (ends as RASN)

[BTRWx]

Unless the warming trend from both ensemble means comes to a halt I'm taking a more cautious route. The parallel overnight euro really winds this thing up to the point that most of it is liquid. Maybe we can squeeze something in, but I need to see more to get excited.

[MacintoshPro]

Parallel euro supports the op for the most part. Only difference is it is a little slower, so the snow thump is more on the order of 2-4" and we get more plain rain after the flip. Will be interesting to watch today where this thing trends.

[CAPE]

Mount Holly from the AFD this morning..I think this is what HM tweeted about last night...

 

TWO MAIN FEATURES ARE
PRESENT TO TRACK WITH REGARDS TO MODELS OR RESPECTIVE ENSEMBLES
CHANGING THE FORECAST TRACK OF THIS SYSTEM IN FUTURE RUNS. 

FIRST IS A LEADING SHORTWAVE WHICH MOVES INTO THE THE OHIO VALLEY
ON MONDAY AND THE SECOND IS THE DEGREE OF MID- LEVEL HEIGHT RISES
THAT OCCUR AHEAD OF THE STORM SYSTEM. A STRONGER SHORTWAVE WOULD
TEND TO PUSH THE OVERALL TROUGH WITH THIS STORM FURTHER EAST.
WHILE A WEAKER SHORTWAVE WOULD ALLOW FOR HIGHER MID- LEVEL HEIGHT
RISES LEADING TO A FURTHER WEST TRACK OF THE LOW.

[RichmondTarHeel]

For those that have access to the information, what points North and West stay all snow on both the GFS and the Euro?  I can really only see the GFS and it looks like Faifax is the cutoff point. 

[BTRWx]

Correct me if I'm wrong, but It's interesting to me that most commercial outlets that provide euro data seem to have their own algorithms for 2m temps. Does stormvista have a similar solution with the para snowfall? Anyone know how reasonable the surface temp algorithms are for the euro and does that specific data come directly from ecmwf? Key points imo if the latter question is a no.