NorEastermass128 Posted December 31, 2013 Share Posted December 31, 2013 Sometimes a side topic comes up and people want to finish a debate/point on something. As long as it doesn't go on past a page I don't see the big deal. Do we really want model threads again? It may work if we keep it to just 0z, 6z, 12z, and 18z all inclusive model threads, but we don't need 18z DGEX and 6z NMM WRF threads clogging the forum. Yes! I'd like to see that. It would be more organized and users could get information more quickly and efficiently. We should try it with 12z today? Link to comment Share on other sites More sharing options...
N. OF PIKE Posted December 31, 2013 Share Posted December 31, 2013 Widespread 12"+??? Ummmmmm This n of pike overrunning snows better pan out and not fizzle in next 24 hrs of modeling or this threat goes from good to long shot . Link to comment Share on other sites More sharing options...
OceanStWx Posted December 31, 2013 Share Posted December 31, 2013 Love those maps, Chris. It's my forecast today, so we'll see what damage I can do. Link to comment Share on other sites More sharing options...
CoastalWx Posted December 31, 2013 Share Posted December 31, 2013 What is the sig of the 280 K surface? Well to put it very simply, 280K is 280 Kelvin first of all. And to make it very simply, that is showing a forecasted projection of how this parcel would travel starting at the location of where the 280K isentrope would be found. Basically it's showing you how this would traverse upwards . Notice how if you follow the product..you see it moving from 850-800-750mb..etc as it moves north and then northeast. It's a complicated product, but that is a very simplistic view for those that might not understand. Link to comment Share on other sites More sharing options...
dendrite Posted December 31, 2013 Share Posted December 31, 2013 Yes! I'd like to see that. It would be more organized and users could get information more quickly and efficiently. We should try it with 12z today?Model thread killed the disco thread star. Link to comment Share on other sites More sharing options...
HoarfrostHubb Posted December 31, 2013 Share Posted December 31, 2013 Thanks, Chris. Link to comment Share on other sites More sharing options...
ORH_wxman Posted December 31, 2013 Share Posted December 31, 2013 This n of pike overrunning snows better pan out and not fizzle in next 24 hrs of modeling or this threat goes from good to long shot . I certainly wouldn't be banking on overrunning being the primary reason to get widespread 12"+ on that map. I'd be going something like low end warning if I had to guess right now. Link to comment Share on other sites More sharing options...
Clinch Leatherwood Posted December 31, 2013 Share Posted December 31, 2013 Man what a slow, ugly evolution on the GFS. That's an epic dryslot developing between the offshore surface low and the WAA stuff. Link to comment Share on other sites More sharing options...
HoarfrostHubb Posted December 31, 2013 Share Posted December 31, 2013 Well to put it very simply, 280K is 280 Kelvin first of all. And to make it very simply, that is showing a forecasted projection of how this parcel would travel starting at the location of where the 280K isentrope would be found. Basically it's showing you how this would traverse upwards . Notice how if you follow the product..you see it moving from 850-800-750mb..etc as it moves north and then northeast. It's a complicated product, but that is a very simplistic view for those that might not understand.It is fascinating to me that a met can pull a map like that up when needed. Is it an in house NWS product that can deliver that?Sorry for the OT Link to comment Share on other sites More sharing options...
Boston-winter08 Posted December 31, 2013 Share Posted December 31, 2013 Model thread killed the disco thread star. Just my input, but it'd be a pain to have to toggle back and forth for discussion around the same storm Link to comment Share on other sites More sharing options...
HoarfrostHubb Posted December 31, 2013 Share Posted December 31, 2013 I certainly wouldn't be banking on overrunning being the primary reason to get widespread 12"+ on that map. I'd be going something like low end warning if I had to guess right now. I could see someone right on the coast (Cape Ann? NH seacoast) getting 10-12" with fronto, but nothing like that depiction Link to comment Share on other sites More sharing options...
Clinch Leatherwood Posted December 31, 2013 Share Posted December 31, 2013 GFS would bring the WAA snows up...first surface low develops off the Carolinas but largely misses...then we wait for whatever else the atmosphere can stir up. I know that absolutely this isn't the same exact situation again, but it seems like we've had this happen a couple of times with these first systems robbing the best upper support that comes later. Link to comment Share on other sites More sharing options...
CoastalWx Posted December 31, 2013 Share Posted December 31, 2013 It is fascinating to me that a met can pull a map like that up when needed. Is it an in house NWS product that can deliver that? Sorry for the OT That is an AWIPS product for NWS. Link to comment Share on other sites More sharing options...
OceanStWx Posted December 31, 2013 Share Posted December 31, 2013 Thanks, Chris. No problem. The isentropic charts are just a good way of viewing WAA processes. Isentropes (which the 280 K surface is) slope up towards the cold side. So a parcel being forced towards the cold air will glide up the surface (because lift is usually an adiabatic process it won't leave the 280 K surface). The faster it moves through pressure levels the stronger the lift, more potential precip, etc. The GFS for example brings parcels from around 900 mb on the south coast to near 750 mb by the time they reach PWM. That's pretty strong WAA lift. Of course this blows up a little when there are diabatic processes like latent heat release going on (then parcels will leave their isentropes). But it's a good way of looking at the atmosphere in 3D rather than being tied to looking at only lift at one level. Link to comment Share on other sites More sharing options...
CT Rain Posted December 31, 2013 Share Posted December 31, 2013 Inverted trough kinda look on the GFS? Link to comment Share on other sites More sharing options...
Tropopause_Fold Posted December 31, 2013 Share Posted December 31, 2013 No problem. The isentropic charts are just a good way of viewing WAA processes. Isentropes (which the 280 K surface is) slope up towards the cold side. So a parcel being forced towards the cold air will glide up the surface (because lift is usually an adiabatic process it won't leave the 280 K surface). The faster it moves through pressure levels the stronger the lift, more potential precip, etc. The GFS for example brings parcels from around 900 mb on the south coast to near 750 mb by the time they reach PWM. That's pretty strong WAA lift. Of course this blows up a little when there are diabatic processes like latent heat release going on (then parcels will leave their isentropes). But it's a good way of looking at the atmosphere in 3D rather than being tied to looking at only lift at one level. will be nice when AWIPS II is released from unidata and the poor non-nws folks can get a hold it Link to comment Share on other sites More sharing options...
OceanStWx Posted December 31, 2013 Share Posted December 31, 2013 It is fascinating to me that a met can pull a map like that up when needed. Is it an in house NWS product that can deliver that? Sorry for the OT We have the option to do isentropic analysis with most of the models (Euro included). These maps I have are special procedures I have built so I can use one click to pull it up. But I think Ryan has posted similar NCEP produced maps for the GFS before. Link to comment Share on other sites More sharing options...
HoarfrostHubb Posted December 31, 2013 Share Posted December 31, 2013 And then the secondary low pops... Link to comment Share on other sites More sharing options...
Zeus Posted December 31, 2013 Share Posted December 31, 2013 Inverted trough kinda look on the GFS? MEGANORLUN Link to comment Share on other sites More sharing options...
ORH_wxman Posted December 31, 2013 Share Posted December 31, 2013 I really like the PVA on the GFS for predawn Friday morning...that would get things going from a CCB standpoint somewhat. Link to comment Share on other sites More sharing options...
Bostonseminole Posted December 31, 2013 Share Posted December 31, 2013 secondary low on the GFS.. interesting.. Link to comment Share on other sites More sharing options...
Damage In Tolland Posted December 31, 2013 Share Posted December 31, 2013 Not bad at all..gonna makes a lot of folks happy and a lot of worriers worry less Link to comment Share on other sites More sharing options...
CoastalWx Posted December 31, 2013 Share Posted December 31, 2013 It's actually a little sharper and negative with the S/W, but still progressive. Link to comment Share on other sites More sharing options...
CoastalWx Posted December 31, 2013 Share Posted December 31, 2013 I really like the PVA on the GFS for predawn Friday morning...that would get things going from a CCB standpoint somewhat. Yeah it really tries after 06z. Link to comment Share on other sites More sharing options...
40/70 Benchmark Posted December 31, 2013 Share Posted December 31, 2013 Inverted trough kinda look on the GFS? :axe: I referenced an event from Feb 2009 that ended up like this...even explicity mentioning the inverted trough garbage, but doubted that it would actually deteriorate to those levels. Link to comment Share on other sites More sharing options...
Clinch Leatherwood Posted December 31, 2013 Share Posted December 31, 2013 Wow, nice look at 500mb at 60+ hours on the GFS. Nice potential there. Good looking system, hopefully this is the beginning of the handoff to the "2nd" part of the system on the models. (<-- think this is where this is going) Link to comment Share on other sites More sharing options...
HoarfrostHubb Posted December 31, 2013 Share Posted December 31, 2013 :axe: I referenced an event from Feb 2009 that ended up like this...even explicity mentioning the inverted trough garbage, but doubted that it would actually deteriorate to those levels. Your favorite winter type of setup... Link to comment Share on other sites More sharing options...
ORH_wxman Posted December 31, 2013 Share Posted December 31, 2013 Well I'm glad it didn't reverse from the 06z run of more amped up on the trough. Hopefully that can trend just a tad sharper. Link to comment Share on other sites More sharing options...
Damage In Tolland Posted December 31, 2013 Share Posted December 31, 2013 You wonder if most places see like a 2-4 type deal during the day Thursday and then it's just light snows until the main deal starts Thursday night into Friday Link to comment Share on other sites More sharing options...
CoastalWx Posted December 31, 2013 Share Posted December 31, 2013 No problem. The isentropic charts are just a good way of viewing WAA processes. Isentropes (which the 280 K surface is) slope up towards the cold side. So a parcel being forced towards the cold air will glide up the surface (because lift is usually an adiabatic process it won't leave the 280 K surface). The faster it moves through pressure levels the stronger the lift, more potential precip, etc. The GFS for example brings parcels from around 900 mb on the south coast to near 750 mb by the time they reach PWM. That's pretty strong WAA lift. Of course this blows up a little when there are diabatic processes like latent heat release going on (then parcels will leave their isentropes). But it's a good way of looking at the atmosphere in 3D rather than being tied to looking at only lift at one level. It's not an easy process to explain to someone for sure. I try to tell people to treat it as an equal density surface where it would travel following this line of equal density. That obviously governed by adiabatic processes. Unsaturated or saturated. Link to comment Share on other sites More sharing options...
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