Yes_Probably_Maybe_No Posted February 3, 2011 Share Posted February 3, 2011 18z GFS Saturday.......valid 7pm Saturday. Not as organized. Differences between the NAM and GFS wrt tracks/temps/precip amounts is almost laughable. Link to comment Share on other sites More sharing options...
Voyager Posted February 3, 2011 Share Posted February 3, 2011 18z GFS Saturday.......valid 7pm Saturday. Not as organized. It really doesn't give anybody much precipitation, except maybe far southeast PA and southern New Jersey. Link to comment Share on other sites More sharing options...
_AR_ Posted February 3, 2011 Share Posted February 3, 2011 lol. This has bust written all over it. Still hoping for a few inches though. Need some snow on the ground for traction on top of this ice. Link to comment Share on other sites More sharing options...
Parsley Posted February 3, 2011 Author Share Posted February 3, 2011 It really doesn't give anybody much precipitation, except maybe far southeast PA and southern New Jersey. I wouldn't put much weight on it, lets see what 00z has to show. Link to comment Share on other sites More sharing options...
Voyager Posted February 3, 2011 Share Posted February 3, 2011 I wouldn't put much weight on it, lets see what 00z has to show. Agreed. The NAM and the GFS are worlds apart at 18z. Can't come to any kind of consensus with that. Link to comment Share on other sites More sharing options...
pasnowmobile Posted February 3, 2011 Share Posted February 3, 2011 NAM/UKIE/ECM/GGEM all have similar solutions closer to the coast... GFS at 18z had the same track as the 18z NOGAPS basically so we know that is not happening. Link to comment Share on other sites More sharing options...
IsentropicLift Posted February 3, 2011 Share Posted February 3, 2011 I think Mt. Holly will likely issue watches for the next tier down late tonight depending on how the 00z models look. It's funny, the GFS has been more organized with this system and the NAM has been the sloppy outlier. At 18z they seem to have switched sides. It all has to do with that northern stream energy coming through the lakes and how quickly it interacts with the coastal. Link to comment Share on other sites More sharing options...
dssbss Posted February 3, 2011 Share Posted February 3, 2011 I think Mt. Holly will likely issue watches for the next tier down late tonight depending on how the 00z models look. It's funny, the GFS has been more organized with this system and the NAM has been the sloppy outlier. At 18z they seem to have switched sides. It all has to do with that northern stream energy coming through the lakes and how quickly it interacts with the coastal. So you think Lehigh and Berks will go into a watch? I'd be surprised especially with a lot of it coming during the day...it will all melt. I'd think advisory at best, but time will tell. Link to comment Share on other sites More sharing options...
IsentropicLift Posted February 3, 2011 Share Posted February 3, 2011 So you think Lehigh and Berks will go into a watch? I'd be surprised especially with a lot of it coming during the day...it will all melt. I'd think advisory at best, but time will tell. well HPC has between 40 & 70% confidence of at least 4" or more in that region. HPC also has a low confidence 10-30% of seeing at least 8". I take that to mean that confidence of seeing at least 6" is probably around 50-60% and meets the criteria for a watch. As it is now, Mt. Holly has NW NJ in the 5-6" range and falling less than 1" short of warning criteria. That northern stream feature moving through is quite impressive and exactly how its being handeled from run to run is keeping the model spread fairly wide. Let's take a look at the 18z NAM at hr 42 - see how sharp/amplified that s/w is? Now let's compare it to the 18z GFS at hr 42 - big difference. The S/W is not as strong/amplified on the new GFS and therefore doesn't lead to the same solution Link to comment Share on other sites More sharing options...
Grothar Posted February 3, 2011 Share Posted February 3, 2011 well HPC has between 40 & 70% confidence of at least 4" or more in that region. HPC also has a low confidence 10-30% of seeing at least 8". I take that to mean that confidence of seeing at least 6" is probably around 50-60% and meets the criteria for a watch. As it is now, Mt. Holly has NW NJ in the 5-6" range and falling less than 1" short of warning criteria. That northern stream feature moving through is quite impressive and exactly how its being handeled from run to run is keeping the model spread fairly wide. Let's take a look at the 18z NAM at hr 42 - see how sharp/amplified that s/w is? Now let's compare it to the 18z GFS at hr 42 - big difference. The S/W is not as strong/amplified on the new GFS and therefore doesn't lead to the same solution Thanks for your fine forensic analysis which leads to this question. Mt. Holly- Mike Gorse- anyway that you can convince HPC that their probability models match the NWS winters storm advisory, winter storm warnings, and winter storm watch criteria? Ice accretion as well for ice storm warning? This would make absolute sense and would give us a heads up on where watches and warnings should be issued. Many posters get confused on this issue as well as the public. Link to comment Share on other sites More sharing options...
winterwarlock Posted February 4, 2011 Share Posted February 4, 2011 wow gotta call Mt Holly out here....4.9 on the snowfall map for Somerville but only .7 for Middlesex County...sorry but there is never a gradient like that. Plus Uptons adjacent snow map shows totals far far less in nearby counties. What is their justification...is it about hugging each model run? Link to comment Share on other sites More sharing options...
tombo82685 Posted February 4, 2011 Share Posted February 4, 2011 I seriously wish we had more cold air for this weekend's storm and not this stale cold. The 18z gfs is very far east and its still mainly rain for phl and immediate area. Link to comment Share on other sites More sharing options...
Parsley Posted February 4, 2011 Author Share Posted February 4, 2011 I seriously wish we had more cold air for this weekend's storm and not this stale cold. The 18z gfs is very far east and its still mainly rain for phl and immediate area. I here ya......even the 18z NAM with the robust storm barely has it cold enough for snow to stick where it is actually snowing. The lack of cold air and time of day could hinder this storm from living up to its potential. We'll find out soon enough. Link to comment Share on other sites More sharing options...
MGorse Posted February 4, 2011 Share Posted February 4, 2011 Thanks for your fine forensic analysis which leads to this question. Mt. Holly- Mike Gorse- anyway that you can convince HPC that their probability models match the NWS winters storm advisory, winter storm warnings, and winter storm watch criteria? Ice accretion as well for ice storm warning? This would make absolute sense and would give us a heads up on where watches and warnings should be issued. Many posters get confused on this issue as well as the public. Probably not because the criteria for warnings and advisories varies across the country. Link to comment Share on other sites More sharing options...
MGorse Posted February 4, 2011 Share Posted February 4, 2011 wow gotta call Mt Holly out here....4.9 on the snowfall map for Somerville but only .7 for Middlesex County...sorry but there is never a gradient like that. Plus Uptons adjacent snow map shows totals far far less in nearby counties. What is their justification...is it about hugging each model run? Keep in mind that posted storm total snow graphic is there with a winter storm watch for a portion of the forecast area. That snow map is not set in stone. It was the dayshifts first take at what they think may happen with the next event. Fine tuning will be likely. Link to comment Share on other sites More sharing options...
dssbss Posted February 4, 2011 Share Posted February 4, 2011 Keep in mind that posted storm total snow graphic is there with a winter storm watch for a portion of the forecast area. That snow map is not set in stone. It was the dayshifts first take at what they think may happen with the next event. Fine tuning will be likely. I definately like those snow maps...I also like the breifing powerpoints that are put out. Link to comment Share on other sites More sharing options...
phlwx Posted February 4, 2011 Share Posted February 4, 2011 Keep in mind that posted storm total snow graphic is there with a winter storm watch for a portion of the forecast area. That snow map is not set in stone. It was the dayshifts first take at what they think may happen with the next event. Fine tuning will be likely. I buy the sharp gradient though...the $64,000 question is who gets shafted and who wins? Link to comment Share on other sites More sharing options...
_AR_ Posted February 4, 2011 Share Posted February 4, 2011 I buy the sharp gradient though...the $64,000 question is who gets shafted and who wins? It is nice to be on the high side of the sharp gradient finally. Although the amounts are not nearly as high as the earlier storms. Link to comment Share on other sites More sharing options...
tombo82685 Posted February 4, 2011 Share Posted February 4, 2011 I buy the sharp gradient though...the $64,000 question is who gets shafted and who wins? IMHO, i would take the line to the rdg to abe line, then after that start cutting off quickly. In these situations where you have a southerly wind push the mid levels warm faster and usually have a more northern extent than the models show. Im also not a fan of atleast for the phl and immediate suburbs of relying on the coastal to get going to drag down the colder air before the precip exits. Link to comment Share on other sites More sharing options...
mattinpa Posted February 4, 2011 Share Posted February 4, 2011 The 18z GFS had a weaker low with less precip, which favors more of a sloppy mix. The NAM solution would likely give most some snow, but I'm not sure how much it would stick. Remember we relied on the coastal to give us our foot of snow for the day, and that worked. It's happened quite a few times in our area. Link to comment Share on other sites More sharing options...
Bilas Posted February 4, 2011 Share Posted February 4, 2011 It is nice to be on the high side of the sharp gradient finally. Although the amounts are not nearly as high as the earlier storms. I seem to be on the low side lately! Wish there were some cold air around. Probably just a cold rain here. Link to comment Share on other sites More sharing options...
am19psu Posted February 4, 2011 Share Posted February 4, 2011 I seriously wish we had more cold air for this weekend's storm and not this stale cold. The 18z gfs is very far east and its still mainly rain for phl and immediate area. High pressure to the east will only help amplify the warm advection, too. Link to comment Share on other sites More sharing options...
Rib Posted February 4, 2011 Share Posted February 4, 2011 I seriously wish we had more cold air for this weekend's storm and not this stale cold. The 18z gfs is very far east and its still mainly rain for phl and immediate area. The next supply of cold air is waiting behind that next clipper which looks to miss us well to the northwest. Too weak to wrap in any. Wouldn't be shocked to have some flakes at the end with some of the stale cold working in behind the low. Link to comment Share on other sites More sharing options...
Quakertown needs snow Posted February 4, 2011 Share Posted February 4, 2011 Link to comment Share on other sites More sharing options...
tombo82685 Posted February 4, 2011 Share Posted February 4, 2011 High pressure to the east will only help amplify the warm advection, too. Yes exactly, which was one of my main arguments at noontime about the 12z gfs being to cold for that system at hr 160 and it would be a lot warmer for that storm to then showed. High pressure sliding off the mid atl coast bringing in southerly flow into the coastal plain before a storm is never good. Link to comment Share on other sites More sharing options...
tombo82685 Posted February 4, 2011 Share Posted February 4, 2011 The next supply of cold air is waiting behind that next clipper which looks to miss us well to the northwest. Too weak to wrap in any. Wouldn't be shocked to have some flakes at the end with some of the stale cold working in behind the low. what you could see happen, that the 18z gfs tries to do. Brings a s/w at the base of the trof and tries to fire a low along the front. If that happens things could get interesting, but your playing devils advocate with that because you want the cold fron to be past you when that storm gets going, which increases the chances of a miss. Also, if the storm form to early it will slow the progression of the front, leading to rain over to snow maybe. Link to comment Share on other sites More sharing options...
Rib Posted February 4, 2011 Share Posted February 4, 2011 what you could see happen, that the 18z gfs tries to do. Brings a s/w at the base of the trof and tries to fire a low along the front. If that happens things could get interesting, but your playing devils advocate with that because you want the cold fron to be past you when that storm gets going, which increases the chances of a miss. Also, if the storm form to early it will slow the progression of the front, leading to rain over to snow maybe. That clipper does look interesting. Wouldn't be the first time we got a suprise event from a coastal popping. Link to comment Share on other sites More sharing options...
Grothar Posted February 4, 2011 Share Posted February 4, 2011 Probably not because the criteria for warnings and advisories varies across the country. Yes I figured that but you would think that when the line was drawn, the computer could add the warning criteria delineation in their database and update the lines according to warning levels. Seems simple enough. You would also think they used county based maps when drawing out their maps. Thanks Mike Link to comment Share on other sites More sharing options...
mattinpa Posted February 4, 2011 Share Posted February 4, 2011 NAM still gives us wrap-around snow. I'll take that and wait for the better chance next week. Link to comment Share on other sites More sharing options...
tombo82685 Posted February 4, 2011 Share Posted February 4, 2011 NAM still gives us wrap-around snow, I'll take that and wait for the better chance next week. for your location it may be an inch if that, that may be generous. The bl is still torched. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.