Pittsburgh/ Western PA Part III

[blackngoldrules]

I just checked the text output from the 06z NAM, its at 19inches by 84 hours, and even had a period of sleet in between but its still snowing at 84. 6z GFS meanwhile had 13 inches on the text for KPIT. DST sucks for model watching, still another hour until the 12z NAM rolls out. At least right now the models are moving towards a solution that seems to give us some good snow vs the last storm we started seeing things fall apart around this time, so fingers crossed we don't see that again.

Yeah, the NAM is really amped up. We know that typically over the years, the NAM tends to overestimate the QPF, especially with storms still 2 or 3 days away.

Another thing that is concerning is the dreaded warm tongue if this thing gets too amped up. We also know that the models tend to underestimate that. Hopefully, the high to our north will be strong enough to keep that south this time. With the track of the low to our southwest, the warm tongue can be an issue.

The storm 2 weeks ago fell apart for us on the Friday right before the storm. The 12z GFS still had us near a foot, then it fell apart from there. At least with this one, we haven't held on for days to a solution. The trend is now and hopefully it'll be our friend for a change.

Sent from my XT897 using Tapatalk

[colonel717]

Yeah, the NAM is really amped up. We know that typically over the years, the NAM tends to overestimate the QPF, especially with storms still 2 or 3 days away.

Another thing that is concerning is the dreaded warm tongue if this thing gets too amped up. We also know that the models tend to underestimate that. Hopefully, the high to our north will be strong enough to keep that south this time. With the track of the low to our southwest, the warm tongue can be an issue.

The storm 2 weeks ago fell apart for us on the Friday right before the storm. The 12z GFS still had us near a foot, then it fell apart from there. At least with this one, we haven't held on for days to a solution. The trend is now and hopefully it'll be our friend for a change.

Sent from my XT897

I fully expect a Charlie Brown moment with this storm.  Not getting sucked in.  Still 60 hours away and way too much can go wrong between now and then.  It will be noon Sunday before I get excited about any solution that shows us with 6+ inches of snow.  Not sure when the storm will be fully sampled.  I know the sw energy has been sampled for a day or so.

[blackngoldrules]

I fully expect a Charlie Brown moment with this storm. Not getting sucked in. Still 60 hours away and way too much can go wrong between now and then. It will be noon Sunday before I get excited about any solution that shows us with 6+ inches of snow. Not sure when the storm will be fully sampled. I know the sw energy has been sampled for a day or so.

I'm the same way right now. I'll just keep checking out the models and discussing the possibilities knowing full well that this can be just another disappointment. We'll see if Lucy pulls the football away from us yet again. Lol

[Stinkbugspecialist]

Were no 60 hrs away we are 48-50 hrs noaa saying early Sunday afternoon start ???

[Stinkbugspecialist]

This storm is different than last time. This is actually going to phase and pv is not as strong and there suggesting this May stall out and dump snow where ever it ends up. So I'm thinking we have a good chance at some plow able snow

[colonel717]

Were no 60 hrs away we are 48-50 hrs noaa saying early Sunday afternoon start ???

Looking at Cobb data, starts around 7 pm

140316/1900Z  61  06010KT  32.3F  SNOW   13:1| 0.5|| 0.00|| 0.00|| 0.039   13:1|  0.5|| 0.00|| 0.00|| 0.04  100|  0|  0140316/2000Z  62  07011KT  31.5F  SNOW   13:1| 1.6|| 0.00|| 0.00|| 0.124   13:1|  2.1|| 0.00|| 0.00|| 0.16  100|  0|  0140316/2100Z  63  07014KT  31.0F  SNOW   13:1| 1.4|| 0.00|| 0.00|| 0.111   13:1|  3.5|| 0.00|| 0.00|| 0.27  100|  0|  0140316/2200Z  64  07015KT  29.9F  SNOW   15:1| 1.1|| 0.00|| 0.00|| 0.072   13:1|  4.6|| 0.00|| 0.00|| 0.35  100|  0|  0140316/2300Z  65  07016KT  28.7F  SNOW   13:1| 1.2|| 0.00|| 0.00|| 0.098   13:1|  5.8|| 0.00|| 0.00|| 0.44  100|  0|  0140317/0000Z  66  07016KT  27.4F  SNOW   12:1| 1.3|| 0.00|| 0.00|| 0.109   13:1|  7.1|| 0.00|| 0.00|| 0.55  100|  0|  0----------------------------------------------+----++-----+-------------++--------------++-------------++-----------+---+---140317/0100Z  67  07015KT  26.3F  SNOW   11:1| 1.2|| 0.00|| 0.00|| 0.115   13:1|  8.4|| 0.00|| 0.00|| 0.67  100|  0|  0140317/0200Z  68  07016KT  25.4F  SNOW   10:1| 1.1|| 0.00|| 0.00|| 0.113   12:1|  9.5|| 0.00|| 0.00|| 0.78  100|  0|  0140317/0300Z  69  07017KT  24.5F  SNOW    9:1| 0.6|| 0.00|| 0.00|| 0.073   12:1| 10.1|| 0.00|| 0.00|| 0.85  100|  0|  0140317/0400Z  70  07017KT  23.6F  SNOW    9:1| 0.5|| 0.00|| 0.00|| 0.059   12:1| 10.7|| 0.00|| 0.00|| 0.91  100|  0|  0140317/0500Z  71  07016KT  22.4F  SNPL    9:1| 0.7|| 0.04|| 0.00|| 0.080   11:1| 11.4|| 0.04|| 0.00|| 0.99   74| 26|  0140317/0600Z  72  07016KT  21.8F  SNPL    3:1| 0.5|| 0.16|| 0.00|| 0.134   11:1| 11.8|| 0.20|| 0.00|| 1.13   41| 59|  0----------------------------------------------+----++-----+-------------++--------------++-------------++-----------+---+---140317/0700Z  73  07014KT  21.1F  SNPL    6:1| 0.5|| 0.05|| 0.00|| 0.088   10:1| 12.4|| 0.24|| 0.00|| 1.21   74| 26|  0140317/0800Z  74  06015KT  20.7F  PL      0:1| 0.0|| 0.14|| 0.00|| 0.070   10:1| 12.4|| 0.38|| 0.00|| 1.28    0|100|  0140317/0900Z  75  07015KT  20.6F  PL      0:1| 0.0|| 0.02|| 0.00|| 0.012   10:1| 12.4|| 0.41|| 0.00|| 1.30    0|100|  0140317/1000Z  76  07016KT  20.4F  PL      0:1| 0.0|| 0.01|| 0.00|| 0.006   10:1| 12.4|| 0.42|| 0.00|| 1.30    0|100|  0140317/1100Z  77  07015KT  20.2F  PL      0:1| 0.0|| 0.01|| 0.00|| 0.005   10:1| 12.4|| 0.43|| 0.00|| 1.31    0|100|  0140317/1200Z  78  07014KT  19.7F  SNOW   13:1| 0.5|| 0.00|| 0.00|| 0.039   10:1| 12.9|| 0.43|| 0.00|| 1.35  100|  0|  0----------------------------------------------+----++-----+-------------++--------------++-------------++-----------+---+---140317/1300Z  79  06014KT  19.5F  SNOW   15:1| 0.9|| 0.00|| 0.00|| 0.063   10:1| 13.8|| 0.43|| 0.00|| 1.41  100|  0|  0140317/1400Z  80  06013KT  19.8F  SNOW   16:1| 0.9|| 0.00|| 0.00|| 0.054   11:1| 14.7|| 0.43|| 0.00|| 1.46  100|  0|  0140317/1500Z  81  06013KT  20.0F  SNOW   12:1| 0.8|| 0.00|| 0.00|| 0.067   11:1| 15.5|| 0.43|| 0.00|| 1.53  100|  0|  0140317/1600Z  82  05013KT  21.1F  SNOW   12:1| 0.4|| 0.00|| 0.00|| 0.037   11:1| 15.9|| 0.43|| 0.00|| 1.57  100|  0|  0140317/1700Z  83  05012KT  22.5F  SNOW    9:1| 0.2|| 0.00|| 0.00|| 0.026   11:1| 16.2|| 0.43|| 0.00|| 1.59  100|  0|  0140317/1800Z  84  05011KT  23.1F  SNOW   14:1| 0.5|| 0.00|| 0.00|| 0.037   11:1| 16.7|| 0.43|| 0.00|| 1.63  100|  0|  0============================================================================================================================

[colonel717]

WOW

 

 Reduced 38%

1024 x 768 (122.86K)

[north pgh]

I sense a Southern trend that puts us on the fringe again.

[colonel717]

 Reduced 38%

1024 x 768 (125.39K)

[colonel717]

 Reduced 38%

[Rdd9108]

Wait a minute I looked at the snowmap and I see a slight south shift that takes us out of the heaviest snow.

[north pgh]

We are looking good but a sharp cutoff near I-80.

If this thing starts moving south like the last one the heavy snows will be at the WV-PA border again and we will be on that dreaded northern edge. I hope I am wrong. Every other storm locks in at this time but when we are in the game it moves either North or South.

Still pessimistic.

[colonel717]

Wait a minute I looked at the snowmap and I see a slight south shift that takes us out of the heaviest snow.

 

 

Attached thumbnail(s)

 Reduced 38%

1024 x 768 (159.11K)

[Rdd9108]

[Rdd9108]

We are looking good but a sharp cutoff near I-80.

If this thing starts moving south like the last one the heavy snows will be at the WV-PA border again and we will be on that dreaded northern edge. I hope I am wrong. Every other storm locks in at this time but when we are in the game it moves either North or South.

Still pessimistic.

This is not like the last storm according the Bernie R. He said the PV should be lifting out and the worry is the strength of the SW.

[blackngoldrules]

Hopefully this doesn't end up being déjà vu. Seems like the low isn't as strong on this run which allows the cold air to push it a little more south. Still a nice hit but the trend moving it back south is concerning. Two weeks ago, it trended south for the 12z run, but still gave us a nice hit. The 18z did us in after that. This would truly be amazing if this ends up missing us or fringing us. The storm this past week never budged and stayed north of us. The one before that was a perfect hit for us and trended south the last 2 days. This area seems to repel snowstorms like no other. We'll see what the GFS shows.

Sent from my XT897 using Tapatalk

[Rdd9108]

Yeah exactly no one panic over one NAM run. Just yesterday some people were calling for a storm cancel but then the 00z shifted things North. With that notion I am still very pessimistic given the seasonal trend of bending us over a barrel and having its way with us.

[RitualOfTheTrout]

Wow that snow map looks familiar   I really hope we don't see this play out like the last storm.. NAM at 12z was a bit weaker and less organized, held more energy back so the PV was able to steer it east a bit sooner. Honestly, I'll take my chances with a fully phased beast. I'd rather go to rain than watch another M/D line and south bulls eye with cirrus clouds and a few flurries here.

 

This run is more in line with the other global models though, should be interesting to see what happens with the energy that gets left behind. I think it likely rolls OTS, so the more that ejects with the first wave the better.

[colonel717]

My wife is flying in at 10:30 pm Sun night from Minneapolis.  I need to know if she should try to get an earlier flight.  It is very expensive to switch flights thru Delta and as we know these systems change.  Hope we have some consistency from the models so I can get a good idea.

[colonel717]

Attached thumbnail(s)

 Reduced 20%

800 x 600 (35.86K)

[north pgh]

 

Attached thumbnail(s)

 Reduced 20%

800 x 600 (35.86K)

 

IT'S GROUNDHOG DAY!!!!

[RitualOfTheTrout]

GFS is lousy... pretty far south. Trough is positive and doesn't close off. You can see at 54 hours the NAM has the energy consolidating in Oklahoma while the GFS is in Mexico.

[blackngoldrules]

Yeah exactly no one panic over one NAM run. Just yesterday some people were calling for a storm cancel but then the 00z shifted things North. With that notion I am still very pessimistic given the seasonal trend of bending us over a barrel and having its way with us.

The 12z GFS puts us over that barrel once again. Yeah, it's dejavu.

[colonel717]

The 12z GFS puts over that barrel once again. Yeah, it's dejavu.

I was starting to get sucked back in.  Thank you GFS for getting me back to reality..

[RitualOfTheTrout]

The 12z GFS puts over that barrel once again. Yeah, it's dejavu.

Well if it plays out like that, at least we weren't strung along for 3-4 days before it fell apart.

[Rdd9108]

Well once again this thing falls apart with the 12z runs. Go ahead WV take our storm away from us for the 20th time this year. Well atleast I didn't get as invested in this one as the last one.

[colonel717]

From NWS Pittsburgh:

SHORT TERM /SATURDAY THROUGH MONDAY/...
SLIGHTLY COOLER AIR SLIDES INTO THE REGION BEHIND A COLD FRONT
THAT PASSES BY SATURDAY MORNING. ADVECTION DOES NOT LOOK
PARTICULARLY STRONG...HOWEVER LINGERING BOUNDARY LAYER MOISTURE
UNDER UNSTABLE NORTHWESTERLY FLOW MAY ALLOW FOR A FEW RAIN AND
SNOW SHOWERS TO LINGER OVER THE REGION INTO THE MORNING HOURS.

THE REAL WEATHER MAKER AND CLEAR SYSTEM TO WATCH WITH INTEREST FOR
OUR AREA IS JUST NOW COMING ONTO THE PACIFIC NORTHWEST AND WESTERN
CANADA COAST...REFLECTED BY FAIRLY STRONG DRYING ON WATER VAPOR
IMAGERY INDICATIVE OF DEEP PENETRATION OF PV INTO THE MIDDLE
TROPOSPHERE ALONG THE PACIFIC COAST. ENERGY ASSOCIATED WITH THIS
SYSTEM EMERGES EAST OF THE ROCKIES ON SATURDAY AND QUICKLY DIGS
INTO THE MID-MISSISSIPPI VALLEY...AS AN UPPER LOW OVER THE
SOUTHWESTERN UNITED STATES SLOWLY TRACKS EASTWARD INTO THE LOWER
MISSISSIPPI VALLEY BY SATURDAY. A FEW VERY INTERESTING UPPER LEVEL
INTERACTIONS SEEM TO BE TAKING PLACE ON THE PREPONDERANCE OF MODEL
SOLUTIONS THAT COULD...I STRESS COULD...END UP WITH A FAIRLY
SIGNIFICANT WINTER WEATHER MAKER TAKING SHAPE OVER THE MIDDLE
ATLANTIC STATES AND OHIO VALLEY BY SUNDAY NIGHT/MONDAY.

FIRST...THE HUDSON BAY LOW REMAINS THE MAIN CONTROLLER OF THE
WEATHER OVER THE NORTHEASTERN UNITED STATES. ITS POSITION SEEMS
LIKELY TO TREND TOWARD QUEBEC DURING THE SHORT TERM PORTION OF THE
FORECAST. THIS PLACES THE MEAN POLAR JET FLOW IN A NORTHWESTERLY
ORIENTATION GREAT LAKES THAT TRENDS FARTHER SOUTH WITH TIME DUE TO
THE SLOW MIGRATION OF THE UPPER LOW.

SECOND...ENERGY CURRENTLY COMING ON SHORE IN THE PACIFIC NORTHWEST
THAT EMERGES IN THE FRONT RANGE WILL LIKELY ACCELERATE THE
EASTWARD EJECTION OF THE LOW OUT OF THE SOUTHWEST. THIS WILL DRAW
THE SUBTROPICAL JET FARTHER NORTHWARD RAPIDLY AS THE UPPER LOW
ASSOCIATED WITH THE MOVES NORTHEASTWARD TOWARD THE OHIO VALLEY.
ADDITIONALLY...WARM ADVECTION IN THE MID LEVELS AHEAD OF THIS
SYSTEM SEEMS LIKELY TO PACK THE MID AND UPPER LEVEL HEIGHT FIELD
ACROSS THE MIDDLE ATLANTIC. THIS SHOULD WORK TO STRENGTHEN THE
POLAR JET AND REORIENT IT IN A MORE WEST TO EAST FASHION ACROSS
THE MIDDLE ATLANTIC. THIS SEEMS INCREASINGLY LIKELY TO LEAVE US
WITH A SCENARIO WHERE THE LEFT EXIT OF THE SUBTROPICAL JET AND
RIGHT ENTRANCE OF THE POLAR JET ARE LIKELY TO COUPLE...RESULTING
IN CYCLOGENESIS IN ASSOCIATION WITH THE NORTHEASTWARD EJECTION OF
THE SYSTEM OUT OF THE SOUTHWEST SOMEWHERE IN THE OHIO VALLEY OR
MIDDLE ATLANTIC.

THE MODEL CONSENSUS CURRENTLY FAVORS CYCLOGENESIS IN THE MID
MISSISSIPPI VALLEY ON SUNDAY...WITH THE SURFACE SYSTEM LIKELY TO
SLIDE INTO THE CENTRAL APPALACHIANS BY SUNDAY NIGHT. THE PRESSURE
GRADIENT AROUND THIS DEEPENING SYSTEM WILL FAVORING RAPIDLY
INCREASING NORTHEASTERLY FLOW OVER OUR REGION...WHICH SEEMS LIKELY
TO MANIFEST ITSELF IN RAPIDLY DECREASING SURFACE TEMPERATURES
GOING INTO SUNDAY NIGHT. AS LIFT ARRIVES IN THE REGION...THIS
SHOULD ALLOW FOR PRECIPITATION TO TREND QUICKLY TOWARD THE WINTRY
VARIETY AS A RESULT AFTER ONSET OF PRECIPITATION.

WHILE THE SURFACE LOW TRACK WILL BE WELL TO OUR SOUTH...STRONG
TILT WITH HEIGHT DUE TO THE STRONGLY BAROCLINIC NATURE OF THIS
SYSTEM MEANS THE 850 MB LOW WILL BE FAVORED TO MOVE OVER OR NEAR
OUR SOUTHEASTERN FORECAST AREA. AS A RESULT...WARM ADVECTION MAY
RESULT JUST ABOVE THE BOUNDARY LAYER THAT MAY AT LEAST PARTIALLY
MELT HYDROMETEORS...AND DUE TO STRONG COLD ADVECTION BELOW THE
MELTING LAYER...IT DOES SEEM A PREFERENCE FOR SLEET WOULD BE
EVIDENT OVER FREEZING RAIN AT THIS TIME. HOW FAR NORTHWARD THIS
POTENTIAL WARM TONGUE MAY EDGE UP IS HIGHLY UNCERTAIN AT THIS
TIME...HOWEVER IT SEEMS MOST PROBABLY TO AT LEAST GET INTO THE
MORGANTOWN AREA OVERNIGHT SUNDAY NIGHT AT THE MOMENT...IF NOT
FARTHER NORTHWARD.

ANOTHER RAMIFICATION OF THE TRACK OF THE 850 MB LOW OVER THE
SOUTHEASTERN CWA WILL LIKELY BE ITS EFFECTS UPON THE LOW AND MID
LEVEL FRONTOGENESIS AND DEFORMATION FIELDS. FAIRLY GOOD AGREEMENT
EXISTS BETWEEN THE NAM AND GFS WITH THESE FIELDS IN FAVORING DEEP
LIFT THROUGH THE DENDRITIC LAYER THROUGH THE NIGHT SUNDAY ALONG
AND NORTHWEST OF THE TRACK OF THE 850 MB LOW DUE TO IMPRESSIVELY
DEEP DEFORMATION ON BOTH MODELS. THESE TWO SOLUTIONS WOULD FAVOR
RAPIDLY DETERIORATING CONDITIONS AND HEAVY SNOWFALL FROM EASTERN
OHIO THROUGH THE PITTSBURGH AREA OVERNIGHT. HOWEVER...THE CANADIAN
AND ECMWF FAVOR THIS BAND BEING A BIT FARTHER TO THE SOUTHEAST
OWING TO A BIT MORE SUBDUED TRACK OF THE 850 MB LOW. AT THE
MOMENT...THE COMBINATION OF UNCERTAINTY IN WARM AIR ALOFT...WARM
GROUND AT ONSET...AND PROBLEMS WITH THE PARTICULAR TRACK HAVE
NECESSITATED A RATHER CONSERVATIVE APPROACH TO THE
FORECAST...HOWEVER THERE IS POTENTIAL FOR WINTER HEADLINES WITH
THIS SYSTEM FROM LATE SUNDAY THROUGH EARLY MONDAY...SO A MENTION
OF THE SYSTEM IN THE HAZARDOUS WEATHER OUTLOOK HAS BEEN MADE.
FRIES

[Rdd9108]

My final call map. I will check the 00z runs but if theres no help I am done. I will be too drunk tomorrow to care.

[north pgh]

From NWS Pittsburgh:

SHORT TERM /SATURDAY THROUGH MONDAY/...

SLIGHTLY COOLER AIR SLIDES INTO THE REGION BEHIND A COLD FRONT

THAT PASSES BY SATURDAY MORNING. ADVECTION DOES NOT LOOK

PARTICULARLY STRONG...HOWEVER LINGERING BOUNDARY LAYER MOISTURE

UNDER UNSTABLE NORTHWESTERLY FLOW MAY ALLOW FOR A FEW RAIN AND

SNOW SHOWERS TO LINGER OVER THE REGION INTO THE MORNING HOURS.

THE REAL WEATHER MAKER AND CLEAR SYSTEM TO WATCH WITH INTEREST FOR

OUR AREA IS JUST NOW COMING ONTO THE PACIFIC NORTHWEST AND WESTERN

CANADA COAST...REFLECTED BY FAIRLY STRONG DRYING ON WATER VAPOR

IMAGERY INDICATIVE OF DEEP PENETRATION OF PV INTO THE MIDDLE

TROPOSPHERE ALONG THE PACIFIC COAST. ENERGY ASSOCIATED WITH THIS

SYSTEM EMERGES EAST OF THE ROCKIES ON SATURDAY AND QUICKLY DIGS

INTO THE MID-MISSISSIPPI VALLEY...AS AN UPPER LOW OVER THE

SOUTHWESTERN UNITED STATES SLOWLY TRACKS EASTWARD INTO THE LOWER

MISSISSIPPI VALLEY BY SATURDAY. A FEW VERY INTERESTING UPPER LEVEL

INTERACTIONS SEEM TO BE TAKING PLACE ON THE PREPONDERANCE OF MODEL

SOLUTIONS THAT COULD...I STRESS COULD...END UP WITH A FAIRLY

SIGNIFICANT WINTER WEATHER MAKER TAKING SHAPE OVER THE MIDDLE

ATLANTIC STATES AND OHIO VALLEY BY SUNDAY NIGHT/MONDAY.

FIRST...THE HUDSON BAY LOW REMAINS THE MAIN CONTROLLER OF THE

WEATHER OVER THE NORTHEASTERN UNITED STATES. ITS POSITION SEEMS

LIKELY TO TREND TOWARD QUEBEC DURING THE SHORT TERM PORTION OF THE

FORECAST. THIS PLACES THE MEAN POLAR JET FLOW IN A NORTHWESTERLY

ORIENTATION GREAT LAKES THAT TRENDS FARTHER SOUTH WITH TIME DUE TO

THE SLOW MIGRATION OF THE UPPER LOW.

SECOND...ENERGY CURRENTLY COMING ON SHORE IN THE PACIFIC NORTHWEST

THAT EMERGES IN THE FRONT RANGE WILL LIKELY ACCELERATE THE

EASTWARD EJECTION OF THE LOW OUT OF THE SOUTHWEST. THIS WILL DRAW

THE SUBTROPICAL JET FARTHER NORTHWARD RAPIDLY AS THE UPPER LOW

ASSOCIATED WITH THE MOVES NORTHEASTWARD TOWARD THE OHIO VALLEY.

ADDITIONALLY...WARM ADVECTION IN THE MID LEVELS AHEAD OF THIS

SYSTEM SEEMS LIKELY TO PACK THE MID AND UPPER LEVEL HEIGHT FIELD

ACROSS THE MIDDLE ATLANTIC. THIS SHOULD WORK TO STRENGTHEN THE

POLAR JET AND REORIENT IT IN A MORE WEST TO EAST FASHION ACROSS

THE MIDDLE ATLANTIC. THIS SEEMS INCREASINGLY LIKELY TO LEAVE US

WITH A SCENARIO WHERE THE LEFT EXIT OF THE SUBTROPICAL JET AND

RIGHT ENTRANCE OF THE POLAR JET ARE LIKELY TO COUPLE...RESULTING

IN CYCLOGENESIS IN ASSOCIATION WITH THE NORTHEASTWARD EJECTION OF

THE SYSTEM OUT OF THE SOUTHWEST SOMEWHERE IN THE OHIO VALLEY OR

MIDDLE ATLANTIC.

THE MODEL CONSENSUS CURRENTLY FAVORS CYCLOGENESIS IN THE MID

MISSISSIPPI VALLEY ON SUNDAY...WITH THE SURFACE SYSTEM LIKELY TO

SLIDE INTO THE CENTRAL APPALACHIANS BY SUNDAY NIGHT. THE PRESSURE

GRADIENT AROUND THIS DEEPENING SYSTEM WILL FAVORING RAPIDLY

INCREASING NORTHEASTERLY FLOW OVER OUR REGION...WHICH SEEMS LIKELY

TO MANIFEST ITSELF IN RAPIDLY DECREASING SURFACE TEMPERATURES

GOING INTO SUNDAY NIGHT. AS LIFT ARRIVES IN THE REGION...THIS

SHOULD ALLOW FOR PRECIPITATION TO TREND QUICKLY TOWARD THE WINTRY

VARIETY AS A RESULT AFTER ONSET OF PRECIPITATION.

WHILE THE SURFACE LOW TRACK WILL BE WELL TO OUR SOUTH...STRONG

TILT WITH HEIGHT DUE TO THE STRONGLY BAROCLINIC NATURE OF THIS

SYSTEM MEANS THE 850 MB LOW WILL BE FAVORED TO MOVE OVER OR NEAR

OUR SOUTHEASTERN FORECAST AREA. AS A RESULT...WARM ADVECTION MAY

RESULT JUST ABOVE THE BOUNDARY LAYER THAT MAY AT LEAST PARTIALLY

MELT HYDROMETEORS...AND DUE TO STRONG COLD ADVECTION BELOW THE

MELTING LAYER...IT DOES SEEM A PREFERENCE FOR SLEET WOULD BE

EVIDENT OVER FREEZING RAIN AT THIS TIME. HOW FAR NORTHWARD THIS

POTENTIAL WARM TONGUE MAY EDGE UP IS HIGHLY UNCERTAIN AT THIS

TIME...HOWEVER IT SEEMS MOST PROBABLY TO AT LEAST GET INTO THE

MORGANTOWN AREA OVERNIGHT SUNDAY NIGHT AT THE MOMENT...IF NOT

FARTHER NORTHWARD.

ANOTHER RAMIFICATION OF THE TRACK OF THE 850 MB LOW OVER THE

SOUTHEASTERN CWA WILL LIKELY BE ITS EFFECTS UPON THE LOW AND MID

LEVEL FRONTOGENESIS AND DEFORMATION FIELDS. FAIRLY GOOD AGREEMENT

EXISTS BETWEEN THE NAM AND GFS WITH THESE FIELDS IN FAVORING DEEP

LIFT THROUGH THE DENDRITIC LAYER THROUGH THE NIGHT SUNDAY ALONG

AND NORTHWEST OF THE TRACK OF THE 850 MB LOW DUE TO IMPRESSIVELY

DEEP DEFORMATION ON BOTH MODELS. THESE TWO SOLUTIONS WOULD FAVOR

RAPIDLY DETERIORATING CONDITIONS AND HEAVY SNOWFALL FROM EASTERN

OHIO THROUGH THE PITTSBURGH AREA OVERNIGHT. HOWEVER...THE CANADIAN

AND ECMWF FAVOR THIS BAND BEING A BIT FARTHER TO THE SOUTHEAST

OWING TO A BIT MORE SUBDUED TRACK OF THE 850 MB LOW. AT THE

MOMENT...THE COMBINATION OF UNCERTAINTY IN WARM AIR ALOFT...WARM

GROUND AT ONSET...AND PROBLEMS WITH THE PARTICULAR TRACK HAVE

NECESSITATED A RATHER CONSERVATIVE APPROACH TO THE

FORECAST...HOWEVER THERE IS POTENTIAL FOR WINTER HEADLINES WITH

THIS SYSTEM FROM LATE SUNDAY THROUGH EARLY MONDAY...SO A MENTION

OF THE SYSTEM IN THE HAZARDOUS WEATHER OUTLOOK HAS BEEN MADE.

FRIES

FWIW- This discussion was before the 12z models.

[RitualOfTheTrout]

From NWS Pittsburgh:

 

That discussion is old, probably written before 12z runs started rolling in. Not that the NWS swings from run to run but I wouldn't be surprised to see that toned down given latest trends.