NYC/PHL Dec 26-27 Boxing Day Blizzard Part 8

[bmc10]

The SPC just put out a mesoscale discussion for our region.

http://www.spc.noaa..../md/md2136.html

Seems very reasonable. If you look at current pressure falls it appears the LP is following the track of models which bring it further west, I think that would be the SREF camp for example.

[bluewave]

Lol did you notice BW, that we're right inside the eastern edge of that blue ellipse

Yeah,it's really going to get going around here.

[WebBreaker63]

I was roaming around the NWS point and click stuff and they had some really high wind speeds forecasted-- like eastern LI 50 mph sustained gusts to 65 mph! Think that can happen?

They had Western LI and the Jersey Shore for 40 mph sustained gusts to 55 mph

They also had a second precip max for snowfall on the Jersey Shore around Toms River - Barnegat (Ocean County) where the range was 12-20 inches. For this area they had me under 10-16.

Ocean County NJ is now under a Blizzard Warning and NWS Mt Holly is calling from 11 to 19" of snow here at the Jersey Shore (Toms River). I am wondering if the snow totals may be on the lesser side of the range. Ocean temp off of Sandy Hook is 36F - cold for this time of year - still above freezing and if this thing gets wrapped up to tight it may cause some mixing issues with temp just at freezing at height of the storm (rain/snow line looks like it gets pretty close at around 1300)- we'll see - either way things will be a mess later this morning. Note: People last night at Christmas party where like snow? What snow? They didn't believe me and I had to show them the weather channel local forecast. They left early to get home to Baltimore last night.

From Mt Holly Forecast Discussion:

WORKING AGAINST VERY ROBUST SNOW TO LIQUID RATIOS ARE STRONG WINDS BELOW

THE SNOW GROWTH REGION AND SOME TEMPERATURES IN THE WARM LAYER

CAPABLE OF GENERATING P-TYPE ISSUES THAT WILL WRAP AROUND THE

DEVELOPING STORM AND TRY TO MOVE OVER LAND. NO MODEL IS

FORECASTING ANY KIND OF A CHANGEOVER ON LAND, AND THE FORECAST

WON`T GO THERE AT THIS POINT. DYNAMIC COOLING OVER LAND LIKELY

WILL BE SUFFICIENT TO STAVE OFF ANY MIXING.

[NJHurricane]

The RUC shows the dryslot reaching SE PA late tonight.

Wonder if we can achieve the dream scenario....massive mesoscale band thump as band rotates across all of NJ into Pa...then second thump as storm rotates back out

[joey]

i dont buy the western track at all. Look at 6z GFS at 6 hours- specifically the SURFACE maps. Low is in same exact position now. The question is- does the low move ENE and then curl or simply NNE.

[A-L-E-X]

Ocean County NJ is now under a Blizzard Warning and NWS Mt Holly is calling from 11 to 19" of snow here at the Jersey Shore (Toms River). I am wondering if the snow totals may be on the lesser side of the range. Ocean temp off of Sandy Hook is 36F - cold for this time of year - still above freezing and if this thing gets wrapped up to tight it may cause some mixing issues with temp just at freezing at height of the storm (rain/snow line looks like it gets pretty close at around 1300)- we'll see - either way things will be a mess later this morning. Note: People last night at Christmas party where like snow? What snow? They didn't believe me and I had to show them the weather channel local forecast. They left early to get home to Baltimore last night.

From Mt Holly Forecast Discussion:

WORKING AGAINST VERY ROBUST SNOW TO LIQUID RATIOS ARE STRONG WINDS BELOW

THE SNOW GROWTH REGION AND SOME TEMPERATURES IN THE WARM LAYER

CAPABLE OF GENERATING P-TYPE ISSUES THAT WILL WRAP AROUND THE

DEVELOPING STORM AND TRY TO MOVE OVER LAND. NO MODEL IS

FORECASTING ANY KIND OF A CHANGEOVER ON LAND, AND THE FORECAST

WON`T GO THERE AT THIS POINT. DYNAMIC COOLING OVER LAND LIKELY

WILL BE SUFFICIENT TO STAVE OFF ANY MIXING.

Lol you shouldnt have showed them the weather channel when they didnt believe you. It would serve them right

How well did you do there in the Millenium Storm? This seems to have some similar components to that event. I believe the SST was about the same back then. The track is further east this time around so you'd probably have to adjust everything in order to be able to compare the two.

[Voyager]

Wonder if we can achieve the dream scenario....massive mesoscale band thump as band rotates across all of NJ into Pa...then second thump as storm rotates back out

As long as that band makes it to the PA coal regions before retreating, I'm all for it!

[bmc10]

i dont buy the western track at all. Look at 6z GFS at 6 hours- specifically the SURFACE maps. Low is in same exact position now. The question is- does the low move ENE and then curl or simply NNE.

Greatest pressure falls are right along the north carolina coast north of cape hatteras. That would place it on the western edge of guidance and more in line with guidance that brings this thing further west. I think this argues in favor of models that tucked the storm closer to the coast such as the euro and sref for example.

[A-L-E-X]

i dont buy the western track at all. Look at 6z GFS at 6 hours- specifically the SURFACE maps. Low is in same exact position now. The question is- does the low move ENE and then curl or simply NNE.

And if this thing actually decides to stall out for awhile.

[joey]

And if this thing actually decides to stall out for awhile.

yep, people rely too much on those damn pressure change maps.

The GFS at 6z has it passing right by HAT.

[SnowGoose69]

That pressure map was posted about 100 times during the 2002 Christmas storm, I was sick of it.

[jdt]

The RUC shows the dryslot reaching SE PA late tonight.

Just woke up and looking a few things over and getting caught up on the events since 12AM. Seems The RUC and the SREF from 3Z remain on the western edge while the NAM GFS are a little more so east. Take the middle road I say. Watch the pressure falls as SPC nicely noted. Also watch bouy obs along the mid atlantic coast for pressure tendencys and wind shifts. The RUC dryslot issue all the way thru much of NJ is an interesting idea but I doubt that would happen to such an extreme manner. I also doubt that at least the eastern most parts of PA do note reach at least minimum warning level snows (6"). It has been pretty well advertised since 12z Christmas eve that the main banding would likley be over or near the NYC metro area up into SE NE. Seems that will probably end up being correct or very close to it. I tend to trust the experts on this one regardless of what I wish to happen or think I might see lol so I will take SPC at there word at this point.

[AnthonyS]

i dont buy the western track at all. Look at 6z GFS at 6 hours- specifically the SURFACE maps. Low is in same exact position now. The question is- does the low move ENE and then curl or simply NNE.

Current pressure fall trends suggest low further west than 06Z GFS progs:

http://weather.unisys.com/surface/sfc_con.php?image=3p&inv=0&t=cur

http://www.twisterdata.com/index.php?prog=forecast&model=GFS&grid=3&model_yyyy=2010&model_mm=12&model_dd=26&model_init_hh=06&fhour=09&parameter=TMPF&level=2&unit=M_ABOVE_GROUND&maximize=n&mode=singlemap&sounding=n&output=image&view=large&archive=false

This is what SPC was referring to.

[bmc10]

yep, people rely too much on those damn pressure change maps.

The GFS at 6z has it passing right by HAT.

The GFS was further NE and progressive with the low, even if only by 50 miles, that can have impacts. Even looking at radar and the orientation of the storm, argues in favor of the heaviest stuff impacting an area 35 miles east and west of NYC in my opinion. That is the the area most likely to receive 12-18 in my opinion. These areas also benefit from increasing forcing, better omega values, alll which could contribute to banding and higher per hour rates.

[joey]

Current pressure fall trends suggest low further west than 06Z GFS progs:

http://weather.unisy...=3p&inv=0&t=cur

http://www.twisterda...e&archive=false

This is what SPC was referring to.

again, that does not mean the low is going to head due North. It simply means that at HAT it is 10-20 miles west.

[joey]

Current pressure fall trends suggest low further west than 06Z GFS progs:

http://weather.unisy...=3p&inv=0&t=cur

http://www.twisterda...e&archive=false

This is what SPC was referring to.

Plus the center of the pressure drops does not represent the future center of the storm.

[Edge Weather]

Yes, but have you seen the latest RUC and SREF? They have the low now hugging the coast with the heaviest axis of snow and wrap around through Eastern PA. Is there any chance that the RUC and SREF have picked up on a track that hugs the coast? Is this possible?

That pressure map was posted about 100 times during the 2002 Christmas storm, I was sick of it.

[Atlas]

Yes, but have you seen the latest RUC. It has the low now hugging the coast with the heaviest axis of snow and wrap around through Eastern PA. Is there any chance that the RUC has picked up on a track that hugs the coast? Is this possible?

I only use the RUC up to 6 hours, beyond that it stinks

[AnthonyS]

Plus the center of the pressure drops does not represent the future center of the storm.

Low pressure tends to follow the area of best pressure falls.

[bmc10]

again, that does not mean the low is going to head due North. It simply means that at HAT it is 10-20 miles west.

Do you live on Long Island or something, I am having trouble determining your motive. Just because the storm is a bit further west, doesn't mean you have to worry. And you are correct no one is indicating it would head due north just that the LP seems to be following the lead of further west guidance and more tucked to the coast. If anything I think this would be more beneficial for the area, except for maybe extreme eastern Long Island. The low deepening more rapidly further south would indicate the phase and a pull back more to the west. Like I said in a zone in either direction 35 miles E or W of NYC 12-18 looks like a good bet with current guidance, radar, and surface obs.

[joey]

Yes, but have you seen the latest RUC. It has the low now hugging the coast with the heaviest axis of snow and wrap around through Eastern PA. Is there any chance that the RUC has picked up on a track that hugs the coast? Is this possible?

IM sorry, the RUC sucks. I would consider the MM5 as a better model, and that's saying somethin.

[joey]

Do you live on Long Island or something, I am having trouble determining your motive. Just because the storm is a bit further west, doesn't mean you have to worry. And you are correct no one is indicating it would head due north just that the LP seems to be following the lead of further west guidance and more tucked to the coast. If anything I think this would be more beneficial for the area, except for maybe extreme eastern Long Island. The low deepening more rapidly further south would indicate the phase and a pull back more to the west. Like I said in a zone in either direction 35 miles E or W of NYC 12-18 looks like a good bet with current guidance, radar, and surface obs.

Not one model outside the RUC supports such a track. That's what I'm saying. I don't buy it.

[bates]

Do you live on Long Island or something, I am having trouble determining your motive. Just because the storm is a bit further west, doesn't mean you have to worry. And you are correct no one is indicating it would head due north just that the LP seems to be following the lead of further west guidance and more tucked to the coast. If anything I think this would be more beneficial for the area, except for maybe extreme eastern Long Island. The low deepening more rapidly further south would indicate the phase and a pull back more to the west. Like I said in a zone in either direction 35 miles E or W of NYC 12-18 looks like a good bet with current guidance, radar, and surface obs.

Excellent post.

[ace0927]

Nothing unusual, the QPF amounts ALWAYS drop as the event is nearing or occurring, they will likely drop a tad more on the 12Z runs...hence why I was saying an average of 13 for the 5 boroughs and not 15-18 as the QPF may have indicated last night or even 20.

seems like the RGEM actually got more robust... significantly so.

[joey]

Low pressure tends to follow the area of best pressure falls.

This is true. However, how many times have those pressure change maps fueled outright weeneism and wishcasting? Too many to count.

[Kaner587]

RUC is not a great model and is always on the northwest fringe/warmer side of things...ALWAYS. It is good for short term precip rates though. Everyone needs to relax, the storm is likely to be somewhere between where the euro progged it (tip of LI) and where the GFS/NAM have it.

[NJHurricane]

I think you should all stop obsessing over the RUC..and take more note of the SREF...as SPC has done with their meso disco. The deeper, tucked in closer scenario is not completely out to lunch imo.

[bmc10]

Not one model outside the RUC supports such a track. That's what I'm saying. I don't buy it.

That is not true, maybe the RUC is to the greatest extent west, but some guidance is further west than the GFS/NAM, such as euro, SREF, high res models. Stop looking at guidance anyways, look at what is currently unfolding, it is pretty obvious. Just even compare the current impacts of the snow in the mid atlantic to what some models were projecting, I am sure the obvious differences will be apparent.

[Kaner587]

I think you should all stop obsessing over the RUC..and take more note of the SREF...as SPC has done with their meso disco

exactly, although being on the western side of the guidance I have no problem following the SREF in the short term being that that is what it was made for.

[AnthonyS]

This is true. However, how many times have those pressure change maps fueled outright weeneism and wishcasting? Too many to count.

While that may be true, pressure tendency is an important diagnostic/prognostic tool, and can't be disregarded because weenies wishcast. Believe me, if those pressure falls were further east, I'd be plenty inclined to think the low was also going to follow suit,