dendrite Posted December 21, 2017 Share Posted December 21, 2017 I'll add that I find it hard to believe PVD/BOS will be colder than 1P1/LCI on Saturday. Link to comment Share on other sites More sharing options...
Whineminster Posted December 21, 2017 Share Posted December 21, 2017 Boston area TV Mets not hitting this event very hard....just saying like 2" of snow than a light glaze with some travel problems Link to comment Share on other sites More sharing options...
dryslot Posted December 21, 2017 Share Posted December 21, 2017 Yikes, Low 20's. Link to comment Share on other sites More sharing options...
dendrite Posted December 21, 2017 Share Posted December 21, 2017 Just now, Ginx snewx said: Is the server in DITs basement? Yeah, but the scripts were written in Harwich. Link to comment Share on other sites More sharing options...
powderfreak Posted December 22, 2017 Share Posted December 22, 2017 16 minutes ago, dendrite said: My alma mater has been working on a hires WRF for our area along with cold air damming graphics. They've been working on a CAD index as well. The CAD graphics aren't available yet, but we do have some WRF images up. The model runs once a day at 00z. So these graphics I'm posting are all the way from 00z last night, but look at how damn cold they are for us. These are 2m temps valid 12z Sat, 18z Sat, and 00z Sun. Damn (dam?) cold. That's awesome! Great to see local interest in a very vulnerable spot for forecasters there... like studying upslope snow in the northern and western areas. The CAD is a huge factor that should have its own forecast parameters to meet criteria. You want to be able to check the boxes for a high end event or know what each criteria might mean for an outcome. Link to comment Share on other sites More sharing options...
wxeyeNH Posted December 22, 2017 Share Posted December 22, 2017 3 minutes ago, Ginx snewx said: Geezus Brian I hope those maps are wrong Love living up here just north of Brian. I can just read all the love you give him and know what's good for him is better for me. Meanwhile wow are we are going to start cold with this storm up here. I'm 16/6F right now. With the snow coming in during the early AM no chance for warming. So its going to be a long struggle up to 32F, that is for sure! Link to comment Share on other sites More sharing options...
Ginx snewx Posted December 22, 2017 Share Posted December 22, 2017 Just now, wxeyeNH said: Love living up here just north of Brian. I can just read all the love you give him and know what's good for him is better for me. Meanwhile wow are we are going to start cold with this storm up here. I'm 16/6F right now. With the snow coming in during the early AM no chance for warming. So its going to be a long struggle up to 32F, that is for sure! if you don't know by now I started Congrats Dendrite back in 07, it has become synonymous with congrats CNE snow belt, these are the situations where you guys just do very well. Link to comment Share on other sites More sharing options...
OceanStWx Posted December 22, 2017 Share Posted December 22, 2017 7 minutes ago, STILL N OF PIKE said: Scott What is worst case you could see having say at least a 25% chance of verifying (Not forecasting) for ASH to NE mass away from shoreline ( regarding ice accretion) Im trying to understand damage potential and how much Qpf could fall as ice. Seems nobody is mentioning the chances of >.25 Seems like its a low confidence forecast, and that eastern areas should prepare for "issues" Based on our forecast compared to model forecasts, the 75% percentile (1 in 4 chance of seeing higher than that amount) is just shy of .4" ice. 0.25" percentage is 62% according to the WPC spread, we're saying 0.3", 0.5" percentage is 2%, so I would say there is a sweet spot between 0.1 and .3" ice that models are keying on. Link to comment Share on other sites More sharing options...
Damage In Tolland Posted December 22, 2017 Share Posted December 22, 2017 18 minutes ago, dendrite said: My alma mater has been working on a hires WRF for our area along with cold air damming graphics. They've been working on a CAD index as well. The CAD graphics aren't available yet, but we do have some WRF images up. The model runs once a day at 00z. So these graphics I'm posting are all the way from 00z last night, but look at how damn cold they are for us. These are 2m temps valid 12z Sat, 18z Sat, and 00z Sun. Damn (dam?) cold. Not in the least bit surprising to this met Link to comment Share on other sites More sharing options...
moneypitmike Posted December 22, 2017 Share Posted December 22, 2017 8 minutes ago, wxeyeNH said: Love living up here just north of Brian. I can just read all the love you give him and know what's good for him is better for me. Meanwhile wow are we are going to start cold with this storm up here. I'm 16/6F right now. With the snow coming in during the early AM no chance for warming. So its going to be a long struggle up to 32F, that is for sure! We had dipped to 16* here as well but it looks like we bumped back up to 17*. Either way, it will be a cool start to whatever comes down. Link to comment Share on other sites More sharing options...
RUNNAWAYICEBERG Posted December 22, 2017 Share Posted December 22, 2017 3 minutes ago, Damage In Tolland said: Not in the least bit surprising to this met It’s going to be a very long, a very dark, and a very cold weekend for you and your fam. Link to comment Share on other sites More sharing options...
weathafella Posted December 22, 2017 Share Posted December 22, 2017 28 minutes ago, RUNNAWAYICEBERG said: It’s going to be a very long, a very dark, and a very cold weekend for you and your fam. You should have been around for October 2011. Kevin’s kids were crying, wife calling lawyers, Kevin shouting weeeee!!!!!! Link to comment Share on other sites More sharing options...
STILL N OF PIKE Posted December 22, 2017 Share Posted December 22, 2017 39 minutes ago, OceanStWx said: Based on our forecast compared to model forecasts, the 75% percentile (1 in 4 chance of seeing higher than that amount) is just shy of .4" ice. 0.25" percentage is 62% according to the WPC spread, we're saying 0.3", 0.5" percentage is 2%, so I would say there is a sweet spot between 0.1 and .3" ice that models are keying on. Are these models the same ones that under do CAD , and usually need to "take em down " with regard to temps I see their value/Validity w snowfall But in this set up i question that. I dont see A Historic ice storm but I wonder if there is Really only 2% chance of .60 or so QPF falling as Freezing rain For the concord,Nh To say NE mass area. Link to comment Share on other sites More sharing options...
OceanStWx Posted December 22, 2017 Share Posted December 22, 2017 1 minute ago, STILL N OF PIKE said: Are these models the same ones that under do CAD , and usually need to "take em down " with regard to temps I see their value/Validity w snowfall But in this set up i question that. I dont see A Historic ice storm but I wonder if there is Really only 2% chance of .60 or so QPF falling as rain For the concord,Nh To say NE mass area. It's complicated because there is input from WPC, it's not like rip and read model ice accumulations, and it is the spread of ice that matters. They ship us the spread, and that spread is applied to our forecast to make the snow and ice probabilities. So that "take 'em down" is baked into it. Link to comment Share on other sites More sharing options...
Damage In Tolland Posted December 22, 2017 Share Posted December 22, 2017 5 minutes ago, OceanStWx said: It's complicated because there is input from WPC, it's not like rip and read model ice accumulations, and it is the spread of ice that matters. They ship us the spread, and that spread is applied to our forecast to make the snow and ice probabilities. So that "take 'em down" is baked into it. Why do they have any weight or bearing on a NWS office forecast? Why can’t they be tossed? I would venture a strong conjecture that they have no clue about topography, microclimates and nuances of “said” areas of the country Link to comment Share on other sites More sharing options...
CoastalWx Posted December 22, 2017 Share Posted December 22, 2017 Hey pickles, as far as damage goes, I think that is more of a function of how much QPF falls. It’s possible that the highest QPF falls in The warmer air near the low level jet. There is no question the temperatures will be cold enough for ice accretion in Nashua. You also have to figure out when the snow will change to freezing rain. Therefore the best chance of borderline damage may be actually just south of Nashua. Link to comment Share on other sites More sharing options...
OceanStWx Posted December 22, 2017 Share Posted December 22, 2017 7 minutes ago, Damage In Tolland said: Why do they have any weight or bearing on a NWS office forecast? Why can’t they be tossed? I would venture a strong conjecture that they have no clue about topography, microclimates and nuances of “said” areas of the country Huh? They don't have any weight in our forecasts. They forecast nationally, we forecast locally, but they provide us with the modeled spread of winter precip. And that's how we do our probabilities (which I know you love). Link to comment Share on other sites More sharing options...
Damage In Tolland Posted December 22, 2017 Share Posted December 22, 2017 2 minutes ago, OceanStWx said: Huh? They don't have any weight in our forecasts. They forecast nationally, we forecast locally, but they provide us with the modeled spread of winter precip. And that's how we do our probabilities (which I know you love). Oh I thought you were saying they gave you your base to build from. And that you had to weight their bad forecasts into yours Link to comment Share on other sites More sharing options...
OceanStWx Posted December 22, 2017 Share Posted December 22, 2017 Just now, Damage In Tolland said: Oh I thought you were saying they gave you your base to build from. And that you had to weight their bad forecasts into yours God no. We toss. Link to comment Share on other sites More sharing options...
RUNNAWAYICEBERG Posted December 22, 2017 Share Posted December 22, 2017 Been over this every winter but I wish we went to an all probability forecast. It would increase awareness that this is not a perfect science while also still providing the public the ‘chances’ a range of amounts would happen. It would actually simplify forecasting imo and prevent the public from throwing tomatoes at weathermen or disregarding what is being said completely. Causing more problems with future events. As dumb as some people are, knowing there is an 80% chance of 12-18” and a 20% chance of 8-12” or however you range it, they can figure it out and still prepare how they see fit. Link to comment Share on other sites More sharing options...
STILL N OF PIKE Posted December 22, 2017 Share Posted December 22, 2017 29 minutes ago, CoastalWx said: Hey pickles, as far as damage goes, I think that is more of a function of how much QPF falls. It’s possible that the highest QPF falls in The warmer air near the low level jet. There is no question the temperatures will be cold enough for ice accretion in Nashua. You also have to figure out when the snow will change to freezing rain. Therefore the best chance of borderline damage may be actually just south of Nashua. Thank you Im also interested in N Andover and West lynnfield Link to comment Share on other sites More sharing options...
CoastalWx Posted December 22, 2017 Share Posted December 22, 2017 Just now, STILL N OF PIKE said: Thank you Im also interested in N Andover and West lynnfield I could see nasty NE MA ice. Link to comment Share on other sites More sharing options...
weathafella Posted December 22, 2017 Share Posted December 22, 2017 19 minutes ago, CoastalWx said: I could see nasty NE MA ice. We’re supposed to go over to friends in Medford tomorrow evening-could be dicey. Link to comment Share on other sites More sharing options...
OceanStWx Posted December 22, 2017 Share Posted December 22, 2017 32 minutes ago, CoastalWx said: I could see nasty NE MA ice. Lunch at my mom's childhood home in Peabody up a 100 foot hill could be interesting Saturday. On a good day that goat path of a road is a tight squeeze, a little ice should do wonders. Link to comment Share on other sites More sharing options...
powderfreak Posted December 22, 2017 Share Posted December 22, 2017 Not bad for snow from the 18z RGEM... almost time for 00z. Link to comment Share on other sites More sharing options...
OceanStWx Posted December 22, 2017 Share Posted December 22, 2017 1 minute ago, powderfreak said: Not bad for snow from the 18z RGEM... almost time for 00z. I do like that stripe of 15-20 mm for warning snows in NH. Forcing really supports that as the zone. Link to comment Share on other sites More sharing options...
BuildingScienceWx Posted December 22, 2017 Share Posted December 22, 2017 NAM definitely a bit more flat at 500, translates to another SE shift with the primary. Close to pushing this South and East of us here in CT. Link to comment Share on other sites More sharing options...
OceanStWx Posted December 22, 2017 Share Posted December 22, 2017 I was just creating some time/height plots for the snow tomorrow across NH, for starters it looks like really favorable snow growth right around midday tomorrow. But we can create these plots anywhere, by moving a set of points around (A through J). Well I discovered that point D was parked over Dendrite. I must've done that on purpose with some previous event. Link to comment Share on other sites More sharing options...
STILL N OF PIKE Posted December 22, 2017 Share Posted December 22, 2017 Would not be surprised if the gradient between ASH and Dentrite is like 7" to 3" Link to comment Share on other sites More sharing options...
dendrite Posted December 22, 2017 Share Posted December 22, 2017 3 minutes ago, OceanStWx said: I was just creating some time/height plots for the snow tomorrow across NH, for starters it looks like really favorable snow growth right around midday tomorrow. But we can create these plots anywhere, by moving a set of points around (A through J). Well I discovered that point D was parked over Dendrite. I must've done that on purpose with some previous event. Nice. Now all I need is my own MOS. I'm waiting to get referenced in the AFDs like PF..."6-8" at the coop." Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.