18z 12/24 model disco

[unknown]

MM5 joins the party:

[Scarlet Pimpernel]

OK... Thanks..... its good

merry xmas

god I hope this trend is real and on the 0z gfs

Amen to that...especially your last line! I wasn't planning on spending late Christmas Eve checking the models, but I guess I'll let myself get sucked in!

[Sickman]

Just want to remind everyone to keep the discussion in this thread related to the model runs. All OT/banter will be deleted. Storm Mode is still in effect. Thanks.

[ORH_wxman]

Did the same bad DATA effect the 18 Z NOGAPS which shifted 200 miles west?

https://www.fnmoc.na...p.054.namer.gif

This should be a flag to the ECM

The nogaps had nowhere to move but west.

[SnowGoose69]

Alot of those lesser known mesoscale models being west is something to note, last event many of them hit New England and were correct.

[cp63]

YEAH but down here in eastern and central VA we are running out of time

NWS and TV are going 1" in RIC and 2-3 in se va

if the 18z GFS is right its going to be 4-8 in central va and 8-12 is se va

and on saturday night and sunday.....

one more jog to the west and we'll be back to your first map....you'd be getting revenge on the pooch....lol....

[A-L-E-X]

The nogaps had nowhere to move but west.

Will, what are your thoughts on this? Still a high amount of uncertainty? I like that the 12z euro ensembles were well west-- that might be telling. Should know more by 0z.

[A-L-E-X]

Alot of those lesser known mesoscale models being west is something to note, last event many of them hit New England and were correct.

Do you think that convection blowing up like that over Texas might be what's causing some of the models to go west?

[ORH_wxman]

Will, what are your thoughts on this? Still a high amount of uncertainty? I like that the 12z euro ensembles were well west-- that might be telling. Should know more by 0z.

Well west of what? I don't think the Euro ensembles have shifted more than 50 miles in the past 48-60 hours. They've been hanging out over (or just east) the benchmark the whole time despite what the OP run has shown.

I'd like to wait until 00z NCEP models before really believing them at face value. I said earlier I thought a trend west was real, but that it just wasn't that big.I could be wrong though.

[donsutherland1]

Glenn is one of the best in the business. At a recent conference in Philly, I had the chance to catch him on TV. He's a real asset to the Philly area.

[thunderman]

You'd think right? I don't get it.

I don't quite get how it's this bad when at face value it appears to match up very well with obs since then, water vapor, and RUC sampling. It may be a case where this is a joke run or two, but it would be really great to see that error appear plainly in terms of water vapor imagery etc.

What I don't get is how the initial diagnostic said nothing was wrong with the NAM, it was only after the GFS came out that problems seemed to appear.

I agree with this fully. Like many others here I have been looking at raw data and sat data all afternoon and have failed to see this supposed "error". It all looks like its matching up to me. IDK, maybe im missing something.....

[A-L-E-X]

Well west of what? I don't think the Euro ensembles have shifted more than 50 miles in the past 48-60 hours. They've been hanging out over (or just east) the benchmark the whole time despite what the OP run has shown.

I'd like to wait until 00z NCEP models before really believing them at face value. I said earlier I thought a trend west was real, but that it just wasn't that big.I could be wrong though.

I havent seen them but someone said "many members were coastal huggers like the GFS". It's in this thread a few pages earlier and in the subforum thread also.

[yoda]

[A-L-E-X]

Well west of what? I don't think the Euro ensembles have shifted more than 50 miles in the past 48-60 hours. They've been hanging out over (or just east) the benchmark the whole time despite what the OP run has shown.

I'd like to wait until 00z NCEP models before really believing them at face value. I said earlier I thought a trend west was real, but that it just wasn't that big.I could be wrong though.

Looks like Harvey is going with 10-15" for your area lol.

[eduggs]

Alot of those lesser known mesoscale models being west is something to note, last event many of them hit New England and were correct.

But many appear to use GFS initialization. Questionable implications? JMA and Nogaps actually provide some utility here I think, crazy as it sounds. But why Euro, UK, GGEM so far offshore? Crazy situation.

Noticed HPC appeared to say the ensembles, including GEFS were useful and not to be thrown out. 12z and 18z GEFS obviously huge hits, and highly dubious.

[Riptide]

The latest RUC is matching up perfectly with the 18z GFS and the shortwave has already passed through the questionable area in Iowa.

[ORH_wxman]

I havent seen them but someone said "many members were coastal huggers like the GFS". It's in this thread a few pages earlier and in the subforum thread also.

Well that would probably mean the spread has increased a lot because the ensemble mean hasn't moved much.

[yoda]

Well that would probably mean the spread has increased a lot because the ensemble mean hasn't moved much.

It had to do with the spaghetti plots I believe

[Eskimo Joe]

I agree with this fully. Like many others here I have been looking at raw data and sat data all afternoon and have failed to see this supposed "error". It all looks like its matching up to me. IDK, maybe im missing something.....

I was thinking the same thing. I'd love to know some specifics. At any rate, check out this satellite.

http://rap.ucar.edu/weather/satellite/displaySat.php?region=US&itype=wv&size=large&endDate=20101224&endTime=-1&duration=6

[A-L-E-X]

It had to do with the spaghetti plots I believe

Ah ok-- that would mean that there would have to be quite a few that were east (or maybe just one or two that were well east?) to balance out the western fringe.

[NortheastPAWx]

ens precip through 18z monday

That's the OP. Here's your ENS:

[nwp]

I am not sure I understand what HPC is looking at here either. Some additional details would be very helpful. I just used an internal tool (adjoint-DAS) to provide a little more information about some of the targeted observations in the region of interest associated with the upper-level s/w across the upper-plains. What is interesting is that one of the in-house analysis and forecast models I run is very similar to the latest global GSI analysis across the region...and shows a similar outcome along the east coast. Oh well, what do I know...I haven't been an operational forecaster in years.

Me, dtk, and you vs HPC now lol.

[WinterWxLuvr]

I saw it mentioned in one of these threads the other day that one of the mets, when they were in college, had to make forecasts strictly from observations, satellite, etc. No models allowed. Question for any mets here who see this. If you had to make a forecast off of the observations and satellite currently, what would you forecast?

[allman15]

WHAT AN AMAZING DAY AND WEEK!

I've never seen anything like this before...such a difference in models so close to a storm, AFTER a flip-flop of both EURO and GFS! Try attempting to make a forecast on TV on such an important weekend.

As for meteorological stuff, we get a special product at NBC10 in Philadelphia called eCast. This is a product from AER in Mass. that creates a MOS based on the EURO ensembles. For example, it gives the POP for every 12 hour period of 01, .10. and .50. A POP of 30 means that 30% of the 51 ensemble members had more than that amount of precip during the period in question. It has had a great track record over the past several years for us.

Curiously, it has had surprisingly low POPs for PHL this week. Even when the operational EURO was hammering us 3 days in a row, the POPs for .50"+ never got over 16%. Today's POPs are 57% for .01", 22% for .10", and 2% for .50"+. That was based on the 00z run.

The eCast maps from the 12z run show the storm track very close to the operational, and precip farther west (but still less than .25" at ACY, and less than .10 at PHL.

If we have the same issues with the 00z runs, I will not be able to sleep tonight (working the 10 and 11pm tomorrow).

My mind goes back to Jan, 2000, when everyone was so sure the storm would stay way offshore. But the radar echoes were way farther west than even the 12 hour forecasts were, so I was able to predict snow up here when other forecasts were still for "partly sunny" (still had no idea we'd get so much). This has taught me to never brag about a forecast before the event, and never say never until the event is over.

Glenn

a very confuning day with the models...lets hope tomorow will bring some resolution.....thanks for posting Glen

[Confuzzled]

Have to view the 12z gfs and therefore 18z nam as suspect since it relies on the gfs. Reliability of the 18z gfs is also suspect. We will know more by 00z but more importantly we are into that nowcasting time frame. Has anyone compared the 12z models and 18z to current radar, satellite and surface obs? In the face of shaky models real time observations are more important. I think most of the models are still out to sea though. Lay out the weenieism, imagined trends, wait to 00z and Nowcasting. Amatuers can hug consistent models. I hope the diversity stays because then tonight is when we get to see the Mets shine.

[Guest someguy]

cant find thw 18z mm5 link? anyone know it?

[Dr No]

10 out of 12 members are a big MA hit. 2 appear to still be light snow/fringes, but good hit further north.

http://www.meteo.psu.edu/~gadomski/ENSPRSNE_18z/f54.html

[AbsoluteVorticity]

I was thinking the same thing. I'd love to know some specifics. At any rate, check out this satellite.

http://rap.ucar.edu/...e=-1&duration=6

You can really see that the northern stream shortwave is really starting to dig, especially in the last several frames. Almost looks like its digging in a strict N-S fashion.

[Eskimo Joe]

You can really see that the northern stream shortwave is really starting to dig, especially in the last several frames. Almost looks like its digging in a strict N-S fashion.

Yes, I love that satellite image.

[Fozz]

18z GFS Ensemble Mean

lol........is that snow in central Florida?