OT: Winter storm for 2/12 - Big Mess of Snow/Sleet/Rain (after minor snowfall on 2/11)

[RU848789]

After a very cold, but not-so-snowy 2nd half of January (for the Philly-NYC area; tons of snow everywhere else in the eastern 1/3 of the USA) and the big warm-up this week, it definitely looks like we're entering a fairly stormy pattern (but fairly normal in temps) starting early next week. First up is a system, which is now near the Aleutians and will come down the west coast, bringing an unusual heavy snowfall to Seattle (6" or more) tomorrow and then to the Sierra-Nevadas (who have feet upon feet of snow from the past few weeks), before traveling eastward across the center of the US, bring substantial snow to the midwest.

The big question for us then becomes whether the storm becomes a full-on cutter to the eastern Great Lakes, which would likely bring a few inches of front end snow on 2/12 with cold air initially in place, followed by warm air flooding in and mostly rain after that, or whether a secondary low forms off the coast and becomes a significant low, bringing more to much more snow to our area, depending on its strength.

Right now, the NWS (Philly and NYC offices) is leaning towards the first solution (maybe a few inches of snow, then mostly rain), as shown by last night's 0Z Euro, which showed a few inches of front-end snow for the area then mostly rain. Understandable, since the last several storms have trended further inland and warmer as the event approached. The NYC discussion is below, as are links to the 33andrain and AmericanWx discussion threads, if you want to read along and see the weenies in action (and some very good pro commentary, too).

However, last night's 0Z UK showed 6" or so of snow for our area, then a mix to rain, as the coastal low became a player. Same thing for this morning's 6Z GFS, which shows significant snow/sleet just inland of 95 and a few inches for 95 (similar to last night's CMC), while the 6Z GFS-FV3 shows a major snow/sleet storm (12" or more) for our whole area (Philly to NYC). Certainly enough potential there to monitor this system.

There also looks to be another potential signficant winter storm for the 2/16 timeframe. Way too far out to predict anything, but it also has the look of a probable mixed bag of precip. Also, there could be a minor snowfall late Sunday/very early Monday (an inch or so) with temps below freezing. Difficult to predict low precip events 3 days out, so also worth watching this one, as the timing would suck for an inch or more of snow, if that occurred.

National Weather Service New York NY
938 AM EST Thu Feb 7 2019

LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...

The high pressure will settle to our south Saturday night into
Sunday as the flow aloft flattens. Shortwave energy embedded in the
flat flow may generate a weak wave of low pressure Sunday night into
early Monday. This system is lift and moisture starved so have
capped PoPs off at slight chance. Any precipitation would be in the
form of snow if it were to occur. Middle and upper level heights are
progged to rise quickly behind this shortwave energy, with another
area of high pressure building to our north and west Monday into
Monday night. Temperatures Saturday night should fall into the teens
and lower 20s with highs in the 30s on Sunday. Slightly warmer
temperatures are forecast Sunday night into Monday.

Forecast certainty is greatly reduced for Tuesday into Wednesday.
The next trough should be moving out of the western states Tuesday
which aids in the development of low pressure across the Central
states. Significant height rises ahead of this system support a
parent low track well to our west, but there are some hints at weak
secondary low development along the Middle Atlantic coast late
Tuesday or Wednesday. The antecedent air mass ahead of this system
late Tuesday/Tuesday night may allow for any precip at the onset to
be snow, but should see a change to liquid Wednesday once the main
system tracks to our west. However, the timing of these occurrences
and changes in PTYPE is still in question. Systems in the extended
have trended warmer for much of this winter and it is quite possible
we are already seeing signs of this occurring in the latest model
runs.

https://forecast.weather.gov/produc...&format=CI&version=1&glossary=1&highlight=off

https://www.33andrain.com/topic/156...forecast-discussion-and-observations/?page=48

https://www.americanwx.com/bb/topic...al-discussion-and-observation-thread/?page=27

2/10 Edit: changed from original title of "Potential winter storm for 2/12-13 - lots of potential outcomes..." to "winter storm for-2-12 - big mess of snow sleet rain after minor snowfall on 2-11"

 

[DJ Spanky]

Calling the Bicker Brothers.....

 

[JERZEE73]

Calling the Bicker Brothers.....

True!

 

[mildone]

No worries. I got the snowblower serviced earlier last fall, which prevented any serious snowfall in our area. Protection should hold up.

Except... I found gas leaking from my generator when I moved it. So perhaps it will be snowmageddon with major power outages.

I should probably go buy a new generator this weekend, just to prevent any power outages.

 

[RU1993]

We are five days out from this storm. Does Murphy start salting now?

 

[bac2therac]

nah i will pass on 6 day analysis of models which have been terrible all year long in that timeframe. Potential is there for our first decent winter weather week but that is all that should be said right now. Individual model runs spitting out amounts mean zero right now.

 

[Knight Shift]

We are five days out from this storm. Does Murphy start salting now?

Now? It started!

 

[RU848789]

nah i will pass on 6 day analysis of models which have been terrible all year long in that timeframe. Potential is there for our first decent winter weather week but that is all that should be said right now. Individual model runs spitting out amounts mean zero right now.

It's 5 days out (mostly a 2/12 event), not 6. Otherwise we agree. You do realize I'm not "analyzing" the models, don't you? I'm sharing the outcomes, briefly, in order to illustrate the large variability in the models, so that hopefully it's clear that trying to forecast amounts, right now, is pointless. The other reason is to simply show that there is potential there for significant snow, but it could also be mostly rain.

 

[Scarlet dollar]

It's 5 days out (mostly a 2/12 event), not 6. Otherwise we agree. You do realize I'm not "analyzing" the models, don't you? I'm sharing the outcomes, briefly, in order to illustrate the large variability in the models, so that hopefully it's clear that trying to forecast amounts, right now, is pointless. The other reason is to simply show that there is potential there for significant snow, but it could also be mostly rain.

Appreciate it. Thank you.

 

[WhiteBus]

Desperate times calls for desperate threads. This thread is like a Seinfeld episode. All about nothing.
The winter is slipping away and every storm has slipped away or underperformed. Pressure is on #s.

 

[FELONIOUSMONK]

I live in Monroe. We have missed everything except for the mid November event. Pitchers and catchers report next week. If it snows I don't care. We are creeping up on spring and baseball.

 

[WhiteBus]

I live in Monroe. We have missed everything except for the mid November event. Pitchers and catchers report next week. If it snows I don't care. We are creeping up on spring and baseball.

And if it snows heavily here the last week in February I don't care as I will be in Florida fir spring training and fishing. Hopefully the same thing occurs as the last time I was in the Tampa area. My flight home from the Bowl game Rutgers played was cancelled an I got a free extra day in Florida.

 

[RU848789]

Desperate times calls for desperate threads. This thread is like a Seinfeld episode. All about nothing.
The winter is slipping away and every storm has slipped away or underperformed. Pressure is on #s.

11/15 overperformed, while several since then underperformed. Why would you think this is "desparate?" I just like winter weather and sharing that interest, which is what 95% of this board does with every post - sharing their interests and opinions. Snarky posts like yours and a few others are why I occasionally debate not making weather posts on this board. Every time I think about doing that, though, many people make supportive posts and PMs (and don't need to repeat that now, lol - let's just focus on the weather from here on).

 

[SirScarlet]

11/15 overperformed, while several since then underperformed. Why would you think this is "desparate?" I just like winter weather and sharing that interest, which is what 95% of this board does with every post - sharing their interests and opinions. Snarky posts like yours and a few others are why I occasionally debate not making weather posts on this board. Every time I think about doing that, though, many people make supportive posts and PMs (and don't need to repeat that now, lol - let's just focus on the weather from here on).

keep posting #s...many of us appreciate these threads!

I will never understand why people jump into a thread that is clearly marked, to complain about it.

weird.

 

[WhiteBus]

11/15 overperformed, while several since then underperformed. Why would you think this is "desparate?" I just like winter weather and sharing that interest, which is what 95% of this board does with every post - sharing their interests and opinions. Snarky posts like yours and a few others are why I occasionally debate not making weather posts on this board. Every time I think about doing that, though, many people make supportive posts and PMs (and don't need to repeat that now, lol - let's just focus on the weather from here on).

To be fair this thread is a day or 2 too early as there really is no consensus for anything, good or bad, right now. 6ABC stating a chance of a mix but rain would prevail. Compared to last year this entire winter has been a complete bust.
If you want to work on a long range forecast work on Tampa the 25th-27th. My first spring trip in over 20 years.

 

[greenknight]

We are five days out from this storm. Does Murphy start salting now?

No he will Declare State of Emergency 1st

 

[cardinal2383]

Agreed. Keep posting. Its enjoyable

 

[RU848789]

After a very cold, but not-so-snowy 2nd half of January (for the Philly-NYC area; tons of snow everywhere else in the eastern 1/3 of the USA) and the big warm-up this week, it definitely looks like we're entering a fairly stormy pattern (but fairly normal in temps) starting early next week. First up is a system, which is now near the Aleutians and will come down the west coast, bringing an unusual heavy snowfall to Seattle (6" or more) tomorrow and then to the Sierra-Nevadas (who have feet upon feet of snow from the past few weeks), before traveling eastward across the center of the US, bring substantial snow to the midwest.

The big question for us then becomes whether the storm becomes a full-on cutter to the eastern Great Lakes, which would likely bring a few inches of front end snow on 2/12 with cold air initially in place, followed by warm air flooding in and mostly rain after that, or whether a secondary low forms off the coast and becomes a significant low, bringing more to much more snow to our area, depending on its strength.

Right now, the NWS (Philly and NYC offices) is leaning towards the first solution (maybe a few inches of snow, then mostly rain), as shown by last night's 0Z Euro, which showed a few inches of front-end snow for the area then mostly rain. Understandable, since the last several storms have trended further inland and warmer as the event approached. The NYC discussion is below, as are links to the 33andrain and AmericanWx discussion threads, if you want to read along and see the weenies in action (and some very good pro commentary, too).

However, last night's 0Z UK showed 6" or so of snow for our area, then a mix to rain, as the coastal low became a player. Same thing for this morning's 6Z GFS, which shows significant snow/sleet just inland of 95 and a few inches for 95 (similar to last night's CMC), while the 6Z GFS-FV3 shows a major snow/sleet storm (12" or more) for our whole area (Philly to NYC). Certainly enough potential there to monitor this system.

There also looks to be another potential signficant winter storm for the 2/16 timeframe. Way too far out to predict anything, but it also has the look of a probable mixed bag of precip. Also, there could be a minor snowfall late Sunday/very early Monday (an inch or so) with temps below freezing. Difficult to predict low precip events 3 days out, so also worth watching this one, as the timing would suck for an inch or more of snow, if that occurred.

National Weather Service New York NY
938 AM EST Thu Feb 7 2019

LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...

The high pressure will settle to our south Saturday night into
Sunday as the flow aloft flattens. Shortwave energy embedded in the
flat flow may generate a weak wave of low pressure Sunday night into
early Monday. This system is lift and moisture starved so have
capped PoPs off at slight chance. Any precipitation would be in the
form of snow if it were to occur. Middle and upper level heights are
progged to rise quickly behind this shortwave energy, with another
area of high pressure building to our north and west Monday into
Monday night. Temperatures Saturday night should fall into the teens
and lower 20s with highs in the 30s on Sunday. Slightly warmer
temperatures are forecast Sunday night into Monday.

Forecast certainty is greatly reduced for Tuesday into Wednesday.
The next trough should be moving out of the western states Tuesday
which aids in the development of low pressure across the Central
states. Significant height rises ahead of this system support a
parent low track well to our west, but there are some hints at weak
secondary low development along the Middle Atlantic coast late
Tuesday or Wednesday. The antecedent air mass ahead of this system
late Tuesday/Tuesday night may allow for any precip at the onset to
be snow, but should see a change to liquid Wednesday once the main
system tracks to our west. However, the timing of these occurrences
and changes in PTYPE is still in question. Systems in the extended
have trended warmer for much of this winter and it is quite possible
we are already seeing signs of this occurring in the latest model
runs.

https://forecast.weather.gov/produc...&format=CI&version=1&glossary=1&highlight=off

https://www.33andrain.com/topic/156...forecast-discussion-and-observations/?page=48

https://www.americanwx.com/bb/topic...al-discussion-and-observation-thread/?page=27

In an unusual occurrence, we actually have at least temporary near consensus on a storm 5 days out. I'm guessing that's just a very unlikely coincidence and we'll see more divergence later. Anyway, every global model is now showing a weaker initial low, cutting towards the eastern Great Lakes and most show a weak secondary low forming near the coast.

This means less precip, but also less warm air intrusion, meaning more snow than rain, but not a huge wintry event (but potentially significant; some sleet/freezing rain are possible also) - more in the range of a 2-4/4-8" kind of event, with a ceiling of 10" and a floor of 1-2". This is looking like a Tuesday morning (starting around rush hour) through early Weds am (wee hours) storm, right now.

Note that, the numbers and maps are per current models and are not a forecast; also, note that all rain is extremely unlikely as currently modeled, but that could change, still, as it's still possible, the system could evolve to be stronger and much milder/wetter with a small amount of snow on the front end. Model snowfall outputs are below, just to show what I'm looking at and, for the record, as I kind of like looking at model evolution over time for a storm; will try to do these twice a day when all the globals run.

12Z GFS

12Z GFS-FV3 (new GFS)

12Z CMC (Canadian)

12Z UK

12Z Euro

 

[RU848789]

To be fair this thread is a day or 2 too early as there really is no consensus for anything, good or bad, right now. 6ABC stating a chance of a mix but rain would prevail. Compared to last year this entire winter has been a complete bust.
If you want to work on a long range forecast work on Tampa the 25th-27th. My first spring trip in over 20 years.

I actually agree it's early, but every time I try to wait until 3-4 days before an event, someone else starts a thread. And as per my last post, oddly we have an unusual consensus right now, which I think is really just a coincidence and that we'll see bigger divergence ahead.

Yes, this winter has been a major bust, so far, especially in comparison to the recent past, wherein the 2010s are on track to be the snowiest decade in NYC's recorded history (since 1869) and 9 of the last 10 and 13 of the last 16 winters there have averaged at or above normal - and NYC is a decent surrogate for at least CNJ/NNJ. Only the 11/15 snowfall has kept this from being a record low snow season, like it has been in Boston with only about 3" so far, while NYC has about 8-9" from what I recall.

Enjoy spring training. Long range models show a cold/snowy pattern for the 2nd half of February, but not ready to pull the trigger on that yet, lol. Wouldn't likely affect Tampa much, as most arctic fronts don't make that far south.

https://www.weather.gov/media/okx/Climate/CentralPark/monthlyseasonalsnowfall.pdf

 

[greenknight]

Ahhhhhhhhh the million$$$ phrase everytime you try to wait SOMEONE ELSE starts a thread

 

[RU848789]

NWS-Philly responded to the model movement towards a weaker primary low to our west and a weak coastal low eventually popping to our SE, meaning less precip and a colder, whiter system in its discussion this afternoon. Will be interesting to see where we go from here, as we're still 4.5 days out. And there's still a chance of an inch or so late Sunday/early Monday.

National Weather Service Mount Holly NJ
332 PM EST Thu Feb 7 2019

LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...

In the big picture, the pattern doesn`t look to change too much
as upper level troughing will tend to dominate over the central
and western CONUS with ridging in the western Atlantic. This
will result in a tendency for the dominant storm track to remain
right along the coast or inland generally favoring rain or
mixed precip events over all snow events. Also, after a reprieve
over the weekend the pattern does look to become more active
through the first half of next week.

In terms of the details, an initial weak disturbance looks to
move through Sunday night into early Monday bringing a bit of
light precipitation...most likely in the form of snow but a
little rain could mix in over the Delmarva and southern NJ. This
shouldn`t amount to too much. This system should scoot off to
our east by late Monday with high pressure moving back in to our
north. Conditions should stay mainly cloudy though with
temperatures near average...highs Monday generally in the 30s to
around 40 south. The bigger concern in the longer range looks
to be a stronger, more moisture laden low progged to move
northward from Texas towards the Great Lakes by later Monday
night into Tuesday. Considering this is still several days out
forecast models actually in relatively good agreement on this so
we`ve raised POPs to likely. Precipitation type will be tricky
though especially since a secondary low may develop right along
or just off the coast which could keep cold air in place longer.
The upshot though is that this could be another mixed precip
event for next Tuesday with snow changing to rain across a good
portion of the area and a period of a wintry mix or icing
possible during the transition. Not confident in the details at
this time though. The good news is the pattern looks to remain
progressive so the system should be moving out by early
Wednesday with fair and seasonable conditions to follow by late
Wednesday into next Thursday.

https://forecast.weather.gov/produc...&format=CI&version=1&glossary=1&highlight=off

 

[RU848789]

Ahhhhhhhhh the million$$$ phrase everytime you try to wait SOMEONE ELSE starts a thread

Yes, because I like to be able to edit the titles to make them more helpful, as a system evolves, while most others who start threads don't do that. And they're easier to find later if I started them. If not for those two items, I wouldn't give a crap about who started the threads. But people like you just like to assume.

 

[mildone]

In an unusual occurrence, we actually have at least temporary near consensus on a storm 5 days out. I'm guessing that's just a very unlikely coincidence and we'll see more divergence later. Anyway, every global model is now showing a weaker initial low, cutting towards the eastern Great Lakes and most show a weak secondary low forming near the coast.

This means less precip, but also less warm air intrusion, meaning more snow than rain, but not a huge wintry event (but potentially significant; some sleet/freezing rain are possible also) - more in the range of a 2-4/4-8" kind of event, with a ceiling of 10" and a floor of 1-2". This is looking like a Tuesday morning (starting around rush hour) through early Weds am (wee hours) storm, right now.

See, just my threat to go out and buy a new generator has shifted the trend away from snowmaggedon. But since I want to get a natural gas whole-house one that's directly wired to the house's electrical system, I probably cannot get it done this quick. Thus we're still looking at a couple inches.

 

[T2Kplus10]

Desperate times calls for desperate threads. This thread is like a Seinfeld episode. All about nothing.
The winter is slipping away and every storm has slipped away or underperformed. Pressure is on #s.

Nice!

 

[T2Kplus10]

keep posting #s...many of us appreciate these threads!

I will never understand why people jump into a thread that is clearly marked, to complain about it.

weird.

I appreciate these threads as well, just for a different reason. :)

 

[knightfan7]

And if it snows heavily here the last week in February I don't care as I will be in Florida fir spring training and fishing. Hopefully the same thing occurs as the last time I was in the Tampa area. My flight home from the Bowl game Rutgers played was cancelled an I got a free extra day in Florida.

Right because it's all about you.:smiley:

 

[DJ Spanky]

I appreciate these threads as well, just for a different reason. :)

You must have an industrial size box of screen wipes by your computer.

 

[RU848789]

In an unusual occurrence, we actually have at least temporary near consensus on a storm 5 days out. I'm guessing that's just a very unlikely coincidence and we'll see more divergence later. Anyway, every global model is now showing a weaker initial low, cutting towards the eastern Great Lakes and most show a weak secondary low forming near the coast.

This means less precip, but also less warm air intrusion, meaning more snow than rain, but not a huge wintry event (but potentially significant; some sleet/freezing rain are possible also) - more in the range of a 2-4/4-8" kind of event, with a ceiling of 10" and a floor of 1-2". This is looking like a Tuesday morning (starting around rush hour) through early Weds am (wee hours) storm, right now.

Note that, the numbers and maps are per current models and are not a forecast; also, note that all rain is extremely unlikely as currently modeled, but that could change, still, as it's still possible, the system could evolve to be stronger and much milder/wetter with a small amount of snow on the front end. Model snowfall outputs are below, just to show what I'm looking at and, for the record, as I kind of like looking at model evolution over time for a storm; will try to do these twice a day when all the globals run.

12Z GFS

12Z GFS-FV3 (new GFS)

12Z CMC (Canadian)

12Z UK

12Z Euro

Looks like most of tonight's 0Z models (7 pm EST data inputs) moved back towards a warmer/wetter solution with less frozen precip for our area vs. today's 12Z models from the late morning/early afternoon, with the exception of the UK, which got snowier. Still seeing a front end thump of maybe 2-4" (which likely includes some sleet, so the depth may be <2-4" in that case, but the frozen mass would be the equivalent of 2-4" of "standard" 10:1 ratio snow) early Tuesday, changing to rain on most of the models by the afternoon as temps reach the upper 30s/low 40s.

Still 4.5 days out from the start of the event and much can change. Mostly rain to mostly snow/sleet are still possible (all rain or all snow are looking less likely and a miss is not going to happen). Models are below - have seen the GFS-FV3, which is showing about 2-4" of snow/sleet, before the rain, but having issues pasting it; the UK is the most bullish with 4-8" of snow for most. NWS discussion is below.

A couple of models are showing 1/2-1" of snow late Sunday/early Monday and the 2/16 event is looking mostly warm/wet on most models, but it's still 8 days away. And finally, the pattern starting around 2/19 has every long range forecaster I know excited (cold/snowy), but given that I've been burned twice this season on that (at least the snow part), I'll refrain from highlighting that any further until we're at least within 9-10 days of it.

National Weather Service Mount Holly NJ
354 AM EST Fri Feb 8 2019

LONG TERM /SATURDAY THROUGH THURSDAY/...

An initial weak disturbance moves through Sunday night into Monday
bringing light precipitation, mostly in the form of snow but a
rain/snow mix should occur over parts of Delmarva and southern New
Jersey. While amounts are anticipated to be on the light side, there
is some uncertainty on the northern extent of the precipitation
shield. This system will have to be watched especially given an
overrunning setup, which can over perform sometimes. This system
should quickly shift offshore by late Monday with high pressure
moving across to our north. Conditions should stay mainly cloudy
though with temperatures near average.

A much stronger and moisture laden system then looks to move
northward from Texas towards the Great Lakes by later Monday night
into Tuesday. Considering this is still several days out, the
guidance is in relatively good agreement on this so the PoPs are on
the higher side (likely). The precipitation types are a challenge,
especially since a secondary low may develop right along or just off
the coast which could keep cold air (at least in the low levels) in
place longer. This could be another mixed precipitation event for
Tuesday with snow changing to rain across a good portion of the area
and even a period of a wintry mix or icing during the transition.
The details are rather uncertain given the setup and evolving
thermal profiles at this time range, therefore the forecast includes
most types of precipitation as derived by a model blend mostly from
a partial thicknesses approach. The pattern though looks to remain
progressive so the system should be moving out by early Wednesday
with drier conditions to follow by late Wednesday into Thursday.

https://forecast.weather.gov/produc...&format=CI&version=1&glossary=1&highlight=off

 

[RUonBrain]

As they say on the CE board, so many “snowflakes” are “triggered” by #s.

Too funny.

 

[scarletrider]

#'s which model has been more accurate this winter?

 

[RUScrew85]

See, just my threat to go out and buy a new generator has shifted the trend away from snowmaggedon. But since I want to get a natural gas whole-house one that's directly wired to the house's electrical system, I probably cannot get it done this quick. Thus we're still looking at a couple inches.

Natural gas whore-house?

 

[mildone]

Natural gas whore-house?

That's why I need the generator. High priced escorts don't work when it gets below 69.

 

[greenknight]

These threads remind me of dickiewavers from volunteer firefighters. They would go out and start fires so they could wave their dickies on the firetrucks with lights on.

Knew a few in the day that started brush fires and dumpster fires just for that reason

 

[RU848789]

Looks like most of tonight's 0Z models (7 pm EST data inputs) moved back towards a warmer/wetter solution with less frozen precip for our area vs. today's 12Z models from the late morning/early afternoon, with the exception of the UK, which got snowier. Still seeing a front end thump of maybe 2-4" (which likely includes some sleet, so the depth may be <2-4" in that case, but the frozen mass would be the equivalent of 2-4" of "standard" 10:1 ratio snow) early Tuesday, changing to rain on most of the models by the afternoon as temps reach the upper 30s/low 40s.

Still 4.5 days out from the start of the event and much can change. Mostly rain to mostly snow/sleet are still possible (all rain or all snow are looking less likely and a miss is not going to happen). Models are below - have seen the GFS-FV3, which is showing about 2-4" of snow/sleet, before the rain, but having issues pasting it; the UK is the most bullish with 4-8" of snow for most. NWS discussion is below.

A couple of models are showing 1/2-1" of snow late Sunday/early Monday and the 2/16 event is looking mostly warm/wet on most models, but it's still 8 days away. And finally, the pattern starting around 2/19 has every long range forecaster I know excited (cold/snowy), but given that I've been burned twice this season on that (at least the snow part), I'll refrain from highlighting that any further until we're at least within 9-10 days of it.

National Weather Service Mount Holly NJ
354 AM EST Fri Feb 8 2019

LONG TERM /SATURDAY THROUGH THURSDAY/...

An initial weak disturbance moves through Sunday night into Monday
bringing light precipitation, mostly in the form of snow but a
rain/snow mix should occur over parts of Delmarva and southern New
Jersey. While amounts are anticipated to be on the light side, there
is some uncertainty on the northern extent of the precipitation
shield. This system will have to be watched especially given an
overrunning setup, which can over perform sometimes. This system
should quickly shift offshore by late Monday with high pressure
moving across to our north. Conditions should stay mainly cloudy
though with temperatures near average.

A much stronger and moisture laden system then looks to move
northward from Texas towards the Great Lakes by later Monday night
into Tuesday. Considering this is still several days out, the
guidance is in relatively good agreement on this so the PoPs are on
the higher side (likely). The precipitation types are a challenge,
especially since a secondary low may develop right along or just off
the coast which could keep cold air (at least in the low levels) in
place longer. This could be another mixed precipitation event for
Tuesday with snow changing to rain across a good portion of the area
and even a period of a wintry mix or icing during the transition.
The details are rather uncertain given the setup and evolving
thermal profiles at this time range, therefore the forecast includes
most types of precipitation as derived by a model blend mostly from
a partial thicknesses approach. The pattern though looks to remain
progressive so the system should be moving out by early Wednesday
with drier conditions to follow by late Wednesday into Thursday.

https://forecast.weather.gov/produc...&format=CI&version=1&glossary=1&highlight=off

So much for the model consensus we had yesterday afternoon, lol - never thought it would last, but we have serious model mayhem right now. Models showing everything from 1-2" of snow/sleet, then mostly rain (GFS), to 6"+ of mostly snow (UK still) and a few in-between at 2-4/3-6" (Euro/CMC) or so. As usual my comments are generally for Philly to NYC near 95; in a setup like this, more snow/sleet is likely NW of 95 and less towards the coast.

I will say this: many pros are pessimistic on this storm bringing more than a few inches of snow, since the primary low is going to our west and the coastal looks weak - normally that means some snow then mostly rain. But given model variability and generally poor forecasting from the NWS and many pros this winter, I'll reserve judgment for a couple more days, i.e., I have no frickin' clue what's going to happen on this one yet.

Will update with the model outputs later. Way too busy at work. Bottom line is we're probably going to need another day or two to know what's likely to happen here. Many solutions still on the table. One comment: starting to see more model support for ~1" of snow Sunday night/Monday morning (and maybe 2" or so south of 276/195), which could be slightly to moderately impactful with temps <32F through the morning rush hour on Monday.

12ZGFS

12Z CMC

12Z UK

12Z Euro

And below is a really interesting comparison between how model output services can differ widely when sharing what should be identical information. In the parent post is the 12Z GFS-FV3 from Tropical Tidbits, which reports about 8-10" of snow for the Philly-NYC corridor, but it includes sleet and counts it the same way it reports snow, i.e., as 10" of either per 1" of liquid, which is flawed, as sleet is usually about 3" of sleet per 1" of liquid (but has the same frozen mass as the snow, just not the same depth). The map shows 8-10" of snow, which is really about ~2" of snow + 2" of sleet (equiv to about 7" of snow).

Second is the 12Z GFS-FV3 from Pivotal Weather, which only shows pure snow at 10" snow per 1" of liquid, but excludes sleet entirely. This is also highly flawed, as the map makes it look like a minor ~2" snowfall, when in reality, we're really talking about ~2" of snow + about 2" of sleet (equivalent to ~7" of regular snow), as per above. I think the TT maps are better, as they at least are truly showing the total mass of frozen precip, which is about 8-10" worth of snow (or 0.8-1.0" of liquid equivalent). At least for shoveling, plowing and driving (apart from visibility), mass is the far more important number, not depth. As if predicting "snowfall" isn't hard enough, lol.

12Z GFS-FV3

 

[bac2therac]

Posting clownmaps from models is worthless at this point

we shall see if this threat follows the same pattern as previous storms which showed decent snowfall in midrange but as we got closer seemed to turn more toward rain

 

[RUPete]

These threads remind me of dickiewavers from volunteer firefighters. They would go out and start fires so they could wave their dickies on the firetrucks with lights on.

Knew a few in the day that started brush fires and dumpster fires just for that reason

There was a bad case of that in the Millington/Long Hill area many years ago with guys throwing objects off the 78 overpass down onto traffic so they could be first on the scene. They were caught, obviously.

 

[goru1869]

We are five days out from this storm. Does Murphy start salting now?

Yes, if the moron has his way. The more the moron salts the more the moron can raise our new rain tax.

 

[RU848789]

Posting clownmaps from models is worthless at this point

we shall see if this threat follows the same pattern as previous storms which showed decent snowfall in midrange but as we got closer seemed to turn more toward rain

Agree and I think I've said that. I'm doing it for the ability to look at them over time to judge performance. I find that fascinating, actually, but people should not be thinking one map or another is going to verify at this point. The one thing I do think they're useful for is seeing if there's a consensus or major trend and we see neither right now.

I also don't believe in seasonal model "trends", i.e., just because the last few have trended warmer/wetter in the last day or two before the event (vs. 11/15, which trended colder/snowier). Each event should be independent and not influenced by a previous event, especially since the setups for each event are very unique.

 

[RU848789]

#'s which model has been more accurate this winter?

None, lol. The Euro has the best verification scores, overall, globally, but they don't have model scores on winter weather events in this area or for any specific type of weather in a specific area that I know of. So, it becomes more anecdotal; I don't know anyone who has a good scoring system that has been shared, to date, but it would be nice to see.

 

[RU4Real]

I could do without all of it. The wings on the RJ were icing up last night on final into EWR. Hard pass.