The PHL/NYC Medium Range Thread - Part 2

[jrodd321]

hr 156 has a central Va accumlating snowfall...other then some snow showers and flurries....this is the threat i think holds some intrest

http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/gfs/12/images/gfs_ten_156m.gif

Looks like one of those events where the precip just doesn't want to go past the cold lol.

[earthlight]

hr 156 has a central Va accumlating snowfall...other then some snow showers and flurries....this is the threat i think holds some intrest

http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/gfs/12/images/gfs_ten_156m.gif

Any storm system that cuts across the country with that -NAO block in place has the potential to produce snowfall on the East coast, so long as the 50/50 block is well in place..as it is on most models thus far. The ECMWF is pretty much the worst case scenario but it seems to be on it's own. Here's the 12z CMC

[tombo82685]

this is from the 0z gem, from last night. Just illustrates how strong this block seems to be. Look at all the retrograding lows into maine then circling around the northeast. Thats just fascinating. For people in maine they probably can't wait to get rid of 2010 with all the retrograding systems

http://www.stanford....0zPrecipGLB.htm

[A-L-E-X]

 Ya know we havent had one of those bowling ball systems that cross the country and exit off the mid atlantic in a few years dumping a stripe of moderate snow across the country-- we used to get at least one of those every winter.  Maybe we will this season. 

[A-L-E-X]

this is from the 0z gem, from last night. Just illustrates how strong this block seems to be. Look at all the retrograding lows into maine then circling around the northeast. Thats just fascinating. For people in maine they probably can't wait to get rid of 2010 with all the retrograding systems

http://www.stanford....0zPrecipGLB.htm

Well if its like the last system-- they probably want it because it brought them heavy snow.  The rest of us just got flurries.

[earthlight]

Between 144-150 hours the 12z Euro retrogrades a surface low into the Gulf of Maine..some light snow into the NYC area. What's more important is that afterwards, it has the surface wave going through the Mid-Atlantic like the GFS. It's strung out and weak, but we get a light snow event at 180 hours.

[tombo82685]

hr 174-186 on the 12z euro brings in some lgt snow to the area. Around the m/d border prob some ice in there also with the 850s going right across the border. This may be the first "legit" threat. The nao is still epically west based, 572-576 thickness over baffin island.

[WeatherX]

Looks interesting later next week on the Euro.....how much precip falls?

[tombo82685]

Looks interesting later next week on the Euro.....how much precip falls?

for this region .1, its lgt...but the threat is there for more.

[earthlight]

The low amplifies off the coast at hr 198. It's a decent depiction aloft with a tremendous block and a weak shortwave tracking west to east across the US and then amplifying.

[Allsnow]

Between 144-150 hours the 12z Euro retrogrades a surface low into the Gulf of Maine..some light snow into the NYC area. What's more important is that afterwards, it has the surface wave going through the Mid-Atlantic like the GFS. It's strung out and weak, but we get a light snow event at 180 hours.

Nice thats what we are looking for at this period just some consistency showing a storm threat...i believe 12/10/09 last year we where all in the dumps and there was a storm threat model to be south of us...we all know how thast turn out.

[WeatherX]

for this region .1, its lgt...but the threat is there for more.

Hey, I'll take .1" at this point

Yeah the threat is there for sure and looks like it could do better....

[tombo82685]

The low amplifies off the coast at hr 198. It's a decent depiction aloft with a tremendous block and a weak shortwave tracking west to east across the US and then amplifying.

john, its going to be interesting with that retrograding low offshore. i think that will also play a role in how strong and far north this comes in future runs.

[earthlight]

Something like this, as far as the depiction at H5, is virtually inevitable with the extremely active Pac Jet and forecasted west based -NAO block.

[Allsnow]

john, its going to be interesting with that retrograding low offshore. i think that will also play a role in how strong and far north this comes in future runs.

Other then the euro, does anyother model have this retrograding enough to give sne and nyc snow?

[earthlight]

Here's something to chew on...currently over Northern Canada the heights are below 492dm. By 140 hours the Euro has 576 heights over Western Greenland and extending west of there.

[earthlight]

Other then the euro, does anyother model have this retrograding enough to give sne and nyc snow?

Not really...I think the CMC has it to a certain extent. The shortwave that enters the flow after is the one to watch I think. It's on the CMC as well.

http://www.meteo.psu.edu/~gadomski/CMC_12z/f162.gif

[tombo82685]

Other then the euro, does anyother model have this retrograding enough to give sne and nyc snow?

the gem has it. I posted a link to it on the other page. The 12z euro yest was even more bullish on the retrograde, but backed off on 0z and brought it back some on 12z.

[Allsnow]

Not really...the shortwave that enters the flow after is the one to watch I think. It's on the CMC as well.

http://www.meteo.psu...MC_12z/f162.gif

Agree.......even with that retrograding low on the euro, it still has us getting preciep from the shortwave so thats good to see. Like you said this is prob our first legit threat with this type of pac......

[tombo82685]

that storm really blows up offshore hr 222 has sub 988 low about 300 miles east of the bm

[daxx]

that storm really blows up offshore hr 222 has sub 988 low about 300 miles east of the bm

Tom, does Pacific look any better ?

[tombo82685]

Tom, does Pacific look any better ?

not really, the block is still there and that storm that blew up would likely become a 50/50. But there is still a trof over alaska with a resemblence of a goa low. Trof is crashing on the west coast with a storm sending a ridge just over the rockies coming into the plains.

[tombo82685]

heres a better illustration at hr 240, h5 map

[Chris L]

DT was saying the 0z ECMWF Esenmbles look better than the operational.... Actually supports a potential storm.

[Isotherm]

DT was saying the 0z ECMWF Esenmbles look better than the operational.... Actually supports a potential storm.

That's all we need at this point, a week away. The facts are: 1) NAO retrogrades into a west based orientation next week, 2) 13th-14th bombing low sets up a 50-50 vortex in SE Canada creating plenty of confluence to our north, 3) AO falls through the floor over the next week as massive height rises occur across the nern latitudes, 4) Short waves will be ejecting ewd from the north pacific trough starting mid next week.

So the players will be on the field, and the pattern conducive for snow, it's just a matter timing the features well. We need enough confluence to keep pcpn as frozen, but not too much so that its forced to the south.

[tombo82685]

12z euro ens are still like the blocking to hold through to day 10

[Rainshadow]

Here is the link, Tom.

As per December 17th deadline looking like the nao>epo. Congrats on becoming a mod, I was having a hard time finding this thread, was looking for a red am.

[am19psu]

As per December 17th deadline looking like the nao>epo. Congrats on becoming a mod, I was having a hard time finding this thread, was looking for a red am.

Thanks, Tony.

Yeah, it looks like the AO/NAO is going to be the big winner. Even with the MJO in Phase 5 now and heading to Phase 6, there just doesn't seem to be an end to the blocking. I'm not particularly bullish on the weekend storm (possible? sure. likely? no.), but if it occurs, we could get an Archembault response out of it. Otherwise, I think we are blocked up through Christmas.

[am19psu]

Also, the GWO has come out of the circle for the first time in a while. It'll be interesting to see if it will go through a full 8-1-2-3-4 progression, or just dive back into the middle. The 8-1-2-3-4 is also a warm signal in the East, but I'm not holding my breath for anything to break the block down.

This is me just wondering aloud, but if the solar factor is driving the high latitude blocking, I wonder if the MJO and GWO data are contaminated by the 80s-00s and the Nina signals aren't well represented in winter? I have zero evidence to back this up, so feel free to tell me I'm an idiot if I am.

[CoastalWx]

Also, the GWO has come out of the circle for the first time in a while. It'll be interesting to see if it will go through a full 8-1-2-3-4 progression, or just dive back into the middle. The 8-1-2-3-4 is also a warm signal in the East, but I'm not holding my breath for anything to break the block down.

This is me just wondering aloud, but if the solar factor is driving the high latitude blocking, I wonder if the MJO and GWO data are contaminated by the 80s-00s and the Nina signals aren't well represented in winter? I have zero evidence to back this up, so feel free to tell me I'm an idiot if I am.

I actually discussed that in the sne thread. I wonder what the phase composites would look like if we included the 50's and 60's during the -nao decadal cycle. Again, maybe it doesn't make much difference, but you have to wonder.