jm1220 Posted March 24, 2014 Share Posted March 24, 2014 It sucks that the low kicks out as it goes up the coast. If not, this would have been a good run. The baroclinic zone is in a horrible spot. The low is forced to go out to sea because the southern stream wave is so progressive and the low forms so far east initially. The upper air flow is too westerly. The phase happens way too late and the storm is already gone by the time the phase happens. I think there's probably a small 6-12" spot on Cape Cod and that's it until Nova Scotia. Link to comment Share on other sites More sharing options...
jm1220 Posted March 24, 2014 Share Posted March 24, 2014 also a pretty good heads up that this might be a miss have been the 5 days in a row of every model having the storm miss east. Models can shift west or east dramatically if the underlying reasons for the miss or the hit aren't there, but this time it was all well forecasted. Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 You know, it develops two lows, and then kills off the one closer to the coast and makes the eastern low the primary one. Why is that? Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 At hour 48 the precip is still brushing the NJ coast while at 06z it was out near the Twin Forks. Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 Somewhat going un noticed, at least by me, is that despite the trough axis being sharper, the flow was more progressive out west than prior runs. We just can't seem to get all the pieces to align with this one. Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 Um, this was a pretty huge shift west with the NAM. If the GFS/other models follows suit with anything close we are back in the game. It seems a low pressure does want to be present closer to the coast where the warm SST anomoly is located. Someone with more knowledge than me can hopefully explain why it kills off the western low in favor of the one further east. Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 It closes off 3 hours faster and as a result roughly 50 miles further SW. Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 The 4k NAM at hour 39 shows a huge blob of precip brushing the NJ coast, NYC and Long Island. So Close. Link to comment Share on other sites More sharing options...
shadowsintherain Posted March 24, 2014 Share Posted March 24, 2014 If everyone has given up on this storm, can someone tell me why the HPC graphic above has us in the "Heavy Snow Possible" area? Link to comment Share on other sites More sharing options...
PB GFI Posted March 24, 2014 Share Posted March 24, 2014 If everyone has given up on this storm, can someone tell me why the HPC graphic above has us in the "Heavy Snow Possible" area? Link to comment Share on other sites More sharing options...
jm1220 Posted March 24, 2014 Share Posted March 24, 2014 Someone with more knowledge than me can hopefully explain why it kills off the western low in favor of the one further east. More of the lift seems to be over the far out to sea low on the 500mb chart. What becomes the main vort seems to be moving out towards that area and is driving more of the lift. Therefore, it kills off the closer low reflection. Link to comment Share on other sites More sharing options...
Capt. Adam Posted March 24, 2014 Share Posted March 24, 2014 This is 24 hour surface snowall ending at 8 am Wednesday but what you see in NJ falls mostly in the 8 pm - 2 am time frame. Mostly .25" - .5" qpf. In NJ, Atlantic County is the new Monmouth County. Link to comment Share on other sites More sharing options...
WintersGrasp Posted March 24, 2014 Share Posted March 24, 2014 Look at the sim radar band of HEAVY SNOW from extreme eastern Maine through Nova Scotia Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 More of the lift seems to be over the far out to sea low on the 500mb chart. What becomes the main vort seems to be moving out towards that area and is driving more of the lift. Therefore, it kills off the closer low reflection. Wouldn't all of the pieces phase together though? This is a result of a sloppy phase initially? Link to comment Share on other sites More sharing options...
Juliancolton Posted March 24, 2014 Share Posted March 24, 2014 More of the lift seems to be over the far out to sea low on the 500mb chart. What becomes the main vort seems to be moving out towards that area and is driving more of the lift. Therefore, it kills off the closer low reflection. The easterly low seems better positioned under the coupled divergent jet streak regions as well... just a combination of things. Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 Look at the sim radar band of HEAVY SNOW from extreme eastern Maine through Nova Scotia Sent from my iPhone Yeah I've seen crappier looking category 3 hurricanes than what the 4k NAM simulated radar is projecting. Link to comment Share on other sites More sharing options...
jm1220 Posted March 24, 2014 Share Posted March 24, 2014 Wouldn't all of the pieces phase together though? This is a result of a sloppy phase initially? Eventually they do as the whole system slides NE. But yeah, it seems to be the result of a too late phase, bad baroclinic zone, and progressive flow. Link to comment Share on other sites More sharing options...
Capt. Adam Posted March 24, 2014 Share Posted March 24, 2014 Look at the sim radar band of HEAVY SNOW from extreme eastern Maine through Nova Scotia Sent from my iPhone Washington County, Maine FTW in the US on this run of the NAM, but even that is less than a foot. ACK < 6". Outside of that, S NJ and Delmarva would have the highest accumulations. All as per 12Z NAM clown maps. Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 What a tough call for Cape Cod and eastern New England. The 4k NAM gives Nantucket Island 0.75"+. Link to comment Share on other sites More sharing options...
donsutherland1 Posted March 24, 2014 Share Posted March 24, 2014 If everyone has given up on this storm, can someone tell me why the HPC graphic above has us in the "Heavy Snow Possible" area? WPC may be relying on assumptions about model biases. From WPC: PROBABILISTIC HEAVY SNOW AND ICING DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 457 AM EDT MON MAR 24 2014 VALID 12Z MON MAR 24 2014 - 12Z THU MAR 27 2014 DAYS 2 AND 3... THE 00Z MODELS CLUSTER BETTER ON THE LOW TRACK...WITH THE 00Z UKMET/ECMWF ADJUSTING TO BETTER AGREE WITH ONE ANOTHER. THE PRIMARY REMAINING DIFFERENCES IS IN TIMING...AS THE GFS/GEFS MEAN AREA FEW HOURS FASTER THAN THE NAM/ECMWF/UKMET. GIVEN THE HISTORICAL FAST BIAS OF THE GFS...MORE WEIGHTING WAS GIVEN TO THE SLOWER CLUSTER OF SOLUTIONS. THIS LEADS TO A THREAT OF MORE QPF AND RESULTANT SNOW ACROSS LONG ISLAND AND SRN/EASTERN NEW ENGLAND. THE SHARP QPF GRADIENTS RESULTS IN A SHARP SNOWFALL GRADIENT...SO UNCERTAINTY REMAINS CONSIDERABLE...WITH ANY TRACK ADJUSTMENTS LEADING TO SIGNIFICANT ADJUSTMENTS IN EXPECTED SNOWFALL. Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 Really good agreement Link to comment Share on other sites More sharing options...
Ed Lizard Posted March 24, 2014 Share Posted March 24, 2014 All the models shifted west. GFS looks good but the precip shield doesn't. Euro is still the wettest model. Euro control run has 3 inches for the area. Except as a check of whether the other ensembles might have been significantly affected by the resolution change and not just by perturbed initial conditions, is there any real value to the Euro run with the op's initial conditions but at reduced T number? Link to comment Share on other sites More sharing options...
jbenedet Posted March 24, 2014 Share Posted March 24, 2014 What is absolutely critical is what is happening between hrs 33 and 39. There are two jet streaks. The first of which is more vigorous and allows for the development of the first surface cyclone that heads further east. The second low forms as a result of a second jet streak, coming behind, over the Carolinas - this is the one we want to predominate. The first low, in my opinion is in a less favorable baroclinic zone (the gulf stream in mind), but gets going earlier, and the cold/warm air advections shift the baroclinic zone such that the second low is in a relatively less favorable pressure fall (surface convergence) zone. To be honest, I think the second low overall is the more favorable one, in terms of dynamics, despite the evolution of this setup. It is very close in my opinion, and it's something to watch very carefully. Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 What is absolutely critical is what is happening between hrs 33 and 39. There are two jet streaks. The first of which is more vigorous and allows for the development of the first surface cyclone that heads further east. The second low forms as a result of a second jet streak, coming behind, over the Carolinas - this is the one we want to predominate. The first low, in my opinion is in a less favorable baroclinic zone (the gulf stream in mind), but gets going earlier, and the cold/warm air advections shift the baroclinic zone such that the second low is in a relatively less favorable pressure fall (surface convergence) zone. To be honest, I think the second low overall is the more favorable one, in terms of dynamics, despite the evolution of this setup. It is very close in my opinion, and it's something to watch very carefully. Agreed, any chance that this first low is just a bogus area of strong convection that the models are not interpreting correctly? Link to comment Share on other sites More sharing options...
Ed Lizard Posted March 24, 2014 Share Posted March 24, 2014 how is this frustrating? the models have been showing a miss for days Just because most of the models most of the runs have been on the right track of the field goal being wide right does't mean a 100 or 200 mile miss by a 950 mb Winter storm isn't frustrating. Back in the my home subforum (everywhere not in Scud missile range of I-95 somewhere), a drought last Summer, and few models ever showed rain, but that didn't make the drought much easier to deal with, Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 The 00z Euro ensemble mean was still 2-6" across the area. When you look at the individual members, a few of them do have the more western low staying as the primary one. Link to comment Share on other sites More sharing options...
MJO812 Posted March 24, 2014 Share Posted March 24, 2014 The 00z Euro ensemble mean was still 2-6" across the area. When you look at the individual members, a few of them do have the more western low staying as the primary one. Out of 51 members, how many of them show at least some accumulations for NYC? Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 Look at how many 00z ECMWF ensemble members were tucked in. That's a huge spread at 48 hours out. Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 Out of 51 members, how many of them show at least some accumulations for NYC? Almost half, and that's for the entire area, not just your house. Link to comment Share on other sites More sharing options...
IsentropicLift Posted March 24, 2014 Share Posted March 24, 2014 Ensemble member #46 has 10"+ from DC to Boston. Ensemble member #48 has 10"+ from BWI to Cape Cod Plenty of members have 6"+ over a large area. Link to comment Share on other sites More sharing options...
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