WinterWxLuvr Posted January 28, 2015 Share Posted January 28, 2015 I kinda disagree with the models doing fine comment. A 50 to 100 mile whiff 48 hours out is not fine. To expect a computer simulation to be accurate to within 50 miles from 48 hours out is nonsense. Link to comment Share on other sites More sharing options...
BryanInMd Posted January 28, 2015 Share Posted January 28, 2015 I kinda disagree with the models doing fine comment. A 50 to 100 mile whiff 48 hours out is not fine. The earth is @24,900 miles in circumference and being modeled in multiple dimensions. On the basis of distance, 50 miles is a 0.2% error. Given the number of input variables and human knowledge required to be applied to an imperfectly measured state of the atmosphere, that is a pretty amazing feat. Given the sparseness of measurement data, I would bet the initial state of the atmosphere ingested into the models is not actually even known to within 0.2% error. Link to comment Share on other sites More sharing options...
WinterWxLuvr Posted January 28, 2015 Share Posted January 28, 2015 The earth is @24,900 miles in circumference and being modeled in multiple dimensions. On the basis of distance, 50 miles is a 0.2% error. Given the number of input variables and human knowledge required to be applied to an imperfectly measured state of the atmosphere, that is a pretty amazing feat. Given the sparseness of measurement data, I would bet the initial state of the atmosphere ingested into the models is not actually even known to within 0.2% error. Well said and measured differently, that kind of accuracy would be to 0.7 degrees 2 dimensionally..while trying to model the atmosphere 3 dimensionally as you said. Link to comment Share on other sites More sharing options...
Amped Posted January 28, 2015 Share Posted January 28, 2015 With all the big snowstorms NYC and NE has seen over the past decade I never thought this one was anything that special. It is like the December 2003 storm which is hardly ever mentioned on the board except it wasn't even as widespread, why was it the storm of the century? I don't care if it produces 30" in Boston, haven't there been like 4 storms in the past 15 years that have produced 30 somewhere near Boston? Link to comment Share on other sites More sharing options...
Ian Posted January 28, 2015 Share Posted January 28, 2015 I don't totally get why it is such a euro fail. It isn't like the model is designed to adjust to where population centers are. It just so happened that NYC was on the border...Even I could see they were in danger. The city got 6-12" and the 12z Euro printed out like 1-1.75" with a super sharp gradient, with the precip backing in. It was more than just standard model noise. It was a bust, but the main issue lies with the recklessly bullish forecast. Not quite.. especially after/during the few runs everyone went nuts over. Starting Jan 25 0z there were three runs with a 3" area over or near the city. Here's the first after clipper contamination was gone from the map.. there were two runs prior that had it to some degree. I think there were perhaps hints it was going to end up giving up the western portion in prior runs but it didn't really bail on NYC to a point of giant concern (other than the ridiculous forecasts) until 12z yesterday.. even there it was close enough not to give up. Plus the NAM runs of course (LOL). I mean yeah the western edge is tough and such but it's not like the Euro was advertising it being close in NYC initially. That said even with it supporting itself for a few runs there was not a whole lot of other support to run all the way to it.. so it's perplexing. If I was more tinfoily I'd say the governors or mayors leaned on NWS. Link to comment Share on other sites More sharing options...
Heisy Posted January 28, 2015 Share Posted January 28, 2015 The EURO was the first model to sniff out that the event could impact NE so at least it gets credit there...One event doesn't make the GFS king. I just wish people would give the RGEM a lot more weight. I think it is the best short range model we have. Link to comment Share on other sites More sharing options...
Bob Chill Posted January 28, 2015 Share Posted January 28, 2015 The EURO was the first model to sniff out that the event could impact NE so at least it gets credit there...One event doesn't make the GFS king. I just wish people would give the RGEM a lot more weight. I think it is the best short range model we have. Navgem had it first by a big margin. Then the CMC Link to comment Share on other sites More sharing options...
mitchnick Posted January 28, 2015 Share Posted January 28, 2015 Navgem had it first by a big margin. Then the CMC GFS had semblances of it on the 0Z 1/22 run this site only lets you go out 120 hours, but I believe it had it a week out almost in blizzard form, then lost it http://beta.wxcaster.com/cgi-bin/GFSCONUSModelArchive.cgi Link to comment Share on other sites More sharing options...
Deck Pic Posted January 28, 2015 Share Posted January 28, 2015 Not quite.. especially after/during the few runs everyone went nuts over. Starting Jan 25 0z there were three runs with a 3" area over or near the city. Here's the first after clipper contamination was gone from the map.. there were two runs prior that had it to some degree. I think there were perhaps hints it was going to end up giving up the western portion in prior runs but it didn't really bail on NYC to a point of giant concern (other than the ridiculous forecasts) until 12z yesterday.. even there it was close enough not to give up. Plus the NAM runs of course (LOL). I mean yeah the western edge is tough and such but it's not like the Euro was advertising it being close in NYC initially. That said even with it supporting itself for a few runs there was not a whole lot of other support to run all the way to it.. so it's perplexing. If I was more tinfoily I'd say the governors or mayors leaned on NWS. Yeah..the Euro had some sick runs until it scaled back right at the end....It was a pretty bad miss, but there have been so many worse misses and reverse busts. It ended up the 18"+ amounts started 30 miles east of Manhattan. They were 30-50 miles from an 18-24" event. And looking now they got 8-12" pretty much. And I am pretty sure the GFS never had 30"+ amounts in Mass...and 25"+ is pretty widespread. I am admittedly a Euro hugger, but 40N had no storm until Friday night. How could anyone take one model's output verbatim, that had almost no snow 24 hours before. Horrible forecast. It makes me wonder if some of the mets in these offices are brilliant scientists and academics, but can't forecast their way out of a paper bag. Maybe they need to take a look at some of the B and C students at mediocre colleges, who might be talented forecasters but suck at advanced calculus. Link to comment Share on other sites More sharing options...
dallen7908 Posted January 28, 2015 Share Posted January 28, 2015 The two to three foot forecasts reminded me of 1993 when our forecast called for 2-3 feet. Didn't verify in my backyard but being able to walk across drifts without sinking more than an inch more than made up for it. Link to comment Share on other sites More sharing options...
Violentweatherfan Posted January 28, 2015 Share Posted January 28, 2015 Hurricane Sandy is still fresh in the minds of many in NYC, and the Euro was all over it. Not sure if this played into any decision making, it might have though. Link to comment Share on other sites More sharing options...
Ger Posted January 28, 2015 Share Posted January 28, 2015 I'll reiterate or resay NE BALTI ZENs point. NYC averages about 8 inches more than BWI and about 18" less than BOS. Some slightly northern and western suburbs of BWI match Western Essex and Morris County NJ and certainly exceed NYC. NYCers think they're on par with BOS. But they don't stick out into the Atlantic enough. Had to be taken down a peg. If BWI were easterly in longitude as NYC the difference in average would be substantially less. Longitude MATTERS. Link to comment Share on other sites More sharing options...
Mercurial Posted January 28, 2015 Share Posted January 28, 2015 I'll reiterate or resay NE BALTI ZENs point. NYC averages about 8 inches more than BWI and about 18" less than BOS. Some slightly northern and western suburbs of BWI match Western Essex and Morris County NJ and certainly exceed NYC. NYCers think they're on par with BOS. But they don't stick out into the Atlantic enough. Had to be taken down a peg. If BWI were easterly in longitude as NYC the difference in average would be substantially less. Longitude MATTERS. If Baltimore were as easterly as NYC, it would have more p-type issues and hence receive less snow than it currently does. IIRC, Atlantic City averages less snow than Baltimore for this reason. That said I agree that the climates are similar. Link to comment Share on other sites More sharing options...
Ger Posted January 28, 2015 Share Posted January 28, 2015 If Baltimore were as easterly as NYC, it would have more p-type issues and hence receive less snow than it currently does. IIRC, Atlantic City averages less snow than Baltimore for this reason. That said I agree that the climates are similar. Atlantic City is practically under NYC as far as longitude is concerned. Maybe BWIs longitude is more Philly than AC. But I see your point Link to comment Share on other sites More sharing options...
Jebman Posted January 28, 2015 Share Posted January 28, 2015 Simple. Never base an all time snow forecast on one model's output. You need Consensus. Link to comment Share on other sites More sharing options...
ohleary Posted January 28, 2015 Share Posted January 28, 2015 Simple. Never base an all time snow forecast on one model's output. You need Consensus. Even better, as one of my professors said, "never forecast a record." Link to comment Share on other sites More sharing options...
PDIII Posted January 28, 2015 Share Posted January 28, 2015 To expect a computer simulation to be accurate to within 50 miles from 48 hours out is nonsense. No we should absolutely expect more. If you think about we have failed as a civilization. In the mid 80s the we all thought we would easily have the cure for cancer by now. Remember when doc in back to the future two... The scene with the rain? That's where I thought we be by now in terms of forecasting. We have no flying cars... No hoverboards... We have facebook and cell phones. Its a f-ing tragedy. If Robert zemekis actually knew how much of a failure the future would be he would have never made that movie. The only thing he did get right was when Marty mcfly gets fired via facetime. So sorry for the tangent but to come full circle... I expect more from the human race in terms of technological advancement. If we set our bar at 75 mile accuracy within 48 hours we are selling our selves short. Link to comment Share on other sites More sharing options...
real Posted January 28, 2015 Share Posted January 28, 2015 Hurricane Sandy is still fresh in the minds of many in NYC, and the Euro was all over it. Not sure if this played into any decision making, it might have though. Not just Sandy, but NYC has sort of been a storm parade over last decade. Something like 5 of the city's top 10 snowfalls have occurred since 2000. Think forecasters there just became over confident and too aggressive in amounts, forgetting what it was like to bust. As others said, going to 2 to 3 feet 24 hours before the first flake fell is insanity, especially for Miller B. And predicting a a "historic" storm is just asking to bust. Even the Blizzard of 93 fell short of "historic" in many cities that received heavy snow. Thinking back to Feb 6 2010 in DC, if I recall, LWX started at about 16 to 24 and didn't jump up to 20 to 30 until after it had already starting snowing that Friday afternoon. But even LWX fell into the "historic" trap, issuing a statement that afternoon stating DC's record of 28 could fall. In fact, where it mattered at DCA, the final tally was like 10 inches short of breaking that record. Link to comment Share on other sites More sharing options...
Heisy Posted January 28, 2015 Share Posted January 28, 2015 Bob, the EURO was the first to show this storm on Friday Night, yeah models showed the event, but the EURO was the first one to show the full phase closed off ULL impacting NE. Link to comment Share on other sites More sharing options...
SLPressure Posted January 28, 2015 Share Posted January 28, 2015 While I think this is a good thread, we have so many awful model busts down here, I don't totally get why we should give 2 sh-its about NYC and why it should be some springboard for model discussion. This **** happens all the time down here. Welcome to 40S, b-itches. I realize this thread is mainly discussing what happened after the coastal took over but what about before that? How about what happened to our classic looking clipper that was supposed to give us a more than average snowfall for these types of storms? Forgive my analysis if there are incongruities. I don't have access to all the model runs and rely a lot on what is said in these forums, but wasn't the Euro ahead of the American models in depicting the digging of the h5 and becoming a Miller B and not giving us much in the way of snow on the front end? Yeah, the American models had us getting the banding once the coastal took over and the Euro didn't, but that is where the GFS and NAM really started to do better for around here. I thought the Euro did a better job up to that point. Am I totally wrong? Given that this pattern is tough for the models (Thanks to all who have made that clear to me) it is nice to see that the new GFS is actually pretty good and that the Euro is "human". And speaking of human, it has been pointed out by almost everyone that it is the humans who may have been the worst (and best, depending on who you call out) predictors in this situation. I applaud the ones who first started the talk about the western edge cut-off and how it could affect so many people, including those in our area. Link to comment Share on other sites More sharing options...
PDIII Posted January 28, 2015 Share Posted January 28, 2015 I realize this thread is mainly discussing what happened after the coastal took over but what about before that? How about what happened to our classic looking clipper that was supposed to give us a more than average snowfall for these types of storms? Forgive my analysis if there are incongruities. I don't have access to all the model runs and rely a lot on what is said in these forums, but wasn't the Euro ahead of the American models in depicting the digging of the h5 and becoming a Miller B and not giving us much in the way of snow on the front end? Yeah, the American models had us getting the banding once the coastal took over and the Euro didn't, but that is where the GFS and NAM really started to do better for around here. I thought the Euro did a better job up to that point. Am I totally wrong? Given that this pattern is tough for the models (Thanks to all who have made that clear to me) it is nice to see that the new GFS is actually pretty good and that the Euro is "human". And speaking of human, it has been pointed out by almost everyone that it is the humans who may have been the worst (and best, depending on who you call out) predictors in this situation. I applaud the ones who first started the talk about the western edge cut-off and how it could affect so many people, including those in our area. Nope the models absolutely nailed our forecast. In the 72 hours leading up... The vast majority if the runs showed like .3 to .6 qpf over a 36 hour period with an inverted trough feature setting up shop over va. That's exactly what happened. Link to comment Share on other sites More sharing options...
CoastalWx Posted January 28, 2015 Share Posted January 28, 2015 I thought the GFS over performed better here. It nailed the area of subsidence that occurred in a part of SE ma, and also deformation band. Link to comment Share on other sites More sharing options...
PDIII Posted January 28, 2015 Share Posted January 28, 2015 I thought the GFS over performed better here. It nailed the area of subsidence that occurred in a part of SE ma, and also deformation band. Cross forum trolling is strictly prohibited. Link to comment Share on other sites More sharing options...
Bob Chill Posted January 28, 2015 Share Posted January 28, 2015 Bob, the EURO was the first to show this storm on Friday Night, yeah models showed the event, but the EURO was the first one to show the full phase closed off ULL impacting NE. I'm an idiot. I was thinking about the miller rAin before it. Navgem was the first to show the low come up out of the gulf. I didn't even look at the navgem for the miller Bail. Link to comment Share on other sites More sharing options...
gymengineer Posted January 29, 2015 Share Posted January 29, 2015 Uhm, this quote?! From famartin?-- So it seems like the models themselves were definitely not the problem in what happened: "This became a bust because on Sunday, a big conference call was held around the region and at the end it was decided that everyone would disregard all models except the 12Z European that day. That's why the NWS forecasts on Sunday afternoon were so high." Link to comment Share on other sites More sharing options...
Amped Posted January 29, 2015 Share Posted January 29, 2015 Uhm, this quote?! From famartin?-- So it seems like the models themselves were definitely not the problem in what happened: "This became a bust because on Sunday, a big conference call was held around the region and at the end it was decided that everyone would disregard all models except the 12Z European that day. That's why the NWS forecasts on Sunday afternoon were so high." We already knew the NWS did that. Link to comment Share on other sites More sharing options...
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