Dsnowx53 Posted November 5, 2012 Share Posted November 5, 2012 Here is the GFS forecast sounding at OKX at 8pm on Wednesday. Decently unstable in the very low levels, but once you get to 950mb, the lapse rate really decreases, so it seems to me that the maximum wind gusts from the GFS would be the 950mb winds. That being said, the 950mb winds are quite impressive, and they are even stronger than they were on the 18z GFS. Here was the observed sounding at OKX from 8pm during the height of Sandy, for comparison sake. Look at how much more unstable this sounding is. Much better for mixing. Link to comment Share on other sites More sharing options...
CooL Posted November 5, 2012 Share Posted November 5, 2012 Euro is tucked into the coast and moves very slowly just off the SE jersey coast. Also looks colder....hah Link to comment Share on other sites More sharing options...
earthlight Posted November 5, 2012 Share Posted November 5, 2012 Completely caught off guard by the earlier model times, but yes. The above post is correct. Link to comment Share on other sites More sharing options...
LovintheWhiteFluff Posted November 5, 2012 Share Posted November 5, 2012 strength? how far off the coast? Link to comment Share on other sites More sharing options...
atownwxwatcher Posted November 5, 2012 Share Posted November 5, 2012 Wow to the 00z ECM...Its definitely tucked close to the coast and it is also colder aloft...interesting! Link to comment Share on other sites More sharing options...
Weathergun Posted November 5, 2012 Share Posted November 5, 2012 0z GFS Bufkit from JFK, at 21z Wed, shows 69kt winds mixing from 900mb to 55kt near the surface, with steep lapse rates up that level. Even stronger winds at 900mb come later in the evening. But lapse rates decline. Link to comment Share on other sites More sharing options...
NYCSuburbs Posted November 5, 2012 Share Posted November 5, 2012 0z ECM almost looks like the CMC with the trend - low a bit more consolidated and tucked into the coast, 850mb temps are colder as well. I don't have the ECM images until the free ones come out but I'd guess it's a snowstorm for the NW NJ and Hudson Valley, perhaps even into the not so far NW suburbs of NYC, while the coast still gets heavy rain and strong winds. Link to comment Share on other sites More sharing options...
uofmiami Posted November 5, 2012 Share Posted November 5, 2012 Winds on 00Z EC definitely strong for the coast: Link to comment Share on other sites More sharing options...
Dsnowx53 Posted November 5, 2012 Share Posted November 5, 2012 We wouldn't be mixing the strong winds just above the deck as efficiently, readily, and frequently as we did during Sandy, and the instability doesn't extend nearly as high in the atmosphere to be able to "grab" the winds that are even stronger. But there is no doubt that the profile favors a few max gusts from the 950mb level being able to mix down to the surface. This would easily translate to a few 60-70 mph gusts for areas along the coast. These winds also won't be as widespread further inland, IMO, as they were during Sandy, since the instability simply is not there to the same extent. Surface temperatures will remain cooler in more inland areas, thus less instability and less mixing. A similar phenomenon occurred in the March, 2010 event where the inversion kept the winds much lighter in LGA, compared to JFK where there was no inversion due to warmer surface temps, and the gusts really took off. We also had the terrifying combination of WAA at the surface with CAA not too far above the ground during Sandy. In this case, there will not be the CAA not too far above the ground. This will temper the instability somewhat. Still a pretty scary situation considering what we're still recovering from. Link to comment Share on other sites More sharing options...
Dsnowx53 Posted November 5, 2012 Share Posted November 5, 2012 0z GFS Bufkit from JFK, at 21z Wed, shows 69kt winds mixing from 900mb to 55kt near the surface, with steep lapse rates up that level. Even stronger winds at 900mb come later in the evening. But lapse rates decline. Good find with the data from 21z, as most sites only have 6-hour increments for the GFS. That is certainly impressive. Those 55kt winds near the surface could be translated to JFK's surface gusts, if the GFS were to be correct. Link to comment Share on other sites More sharing options...
Dsnowx53 Posted November 5, 2012 Share Posted November 5, 2012 Completely caught off guard by the earlier model times, but yes. The above post is correct. I think we would need the Euro to "bomb out" a bit later so that we can fully take advantage of the dynamics, instead of having a storm with waning dynamics. But it was definitely a step in the right direction. Link to comment Share on other sites More sharing options...
Ericjcrash Posted November 5, 2012 Share Posted November 5, 2012 I think we would need the Euro to "bomb out" a bit later so that we can fully take advantage of the dynamics, instead of having a storm with waning dynamics. But it was definitely a step in the right direction. Surely its making it interesting. Made me LOL. Link to comment Share on other sites More sharing options...
Dsnowx53 Posted November 5, 2012 Share Posted November 5, 2012 Surely its making it interesting. Made me LOL. lol yeah I definitely was not expecting that. I still really think we're going to need much better dynamics to get snowfall into areas that aren't significantly elevated (along with the Euro scenario being much more correct than the GFS), but taking this run verbatim, areas away from the coast probably see some wet flakes and temps in the mid to upper 30s. Link to comment Share on other sites More sharing options...
LocoAko Posted November 5, 2012 Share Posted November 5, 2012 From tonight's 00Z GFS for JFK, you can see the wind max come in (my time stamps have been messed up lately for some reason, so I didn't include them). The yellow line is the mixed-layer height, and the green line is the transport wind speed down to the surface. You can readily see that while during the height of the storm the strongest winds are above the mixed layer (which crashes shortly after precipitation sets in), there are still 60 kt winds available, and thus 50kts of transport are being shown, again supporting gusts of 55-60MPH. Also noteworthy is the forecast 35-40 kt surface winds. Link to comment Share on other sites More sharing options...
Weathergun Posted November 5, 2012 Share Posted November 5, 2012 I think we would need the Euro to "bomb out" a bit later so that we can fully take advantage of the dynamics, instead of having a storm with waning dynamics. But it was definitely a step in the right direction. I agree. The Euro and GFS bomb it out east of Delaware, then weaken it from there. Link to comment Share on other sites More sharing options...
earthlight Posted November 5, 2012 Share Posted November 5, 2012 ^Nice way to illustrate it..one thing I think is worth noting is with the less favorable lapse rates and instability this should be more limited to coastal areas (doug alluded to this above )... but even there we're seeing signals for 10m sustained winds of 30+mph which is nothing to sneeze at. The warm seclusion on the GFS runs has been pretty cool to see...pretty awesome to see two powerful storms back to back like this. Obviously Sandy was an entirely different beast but, assuming the guidance isn't out to lunch, this is a more tightly-wound storm capable of producing some solid wind gusts as well. It will be interesting to see how the cold air holds up in the profiles to the north and west and especially in the higher elevations. If it all works out this could be a serious paste snow for Sussex and Orange Co. Link to comment Share on other sites More sharing options...
CooL Posted November 5, 2012 Share Posted November 5, 2012 So the coast looks to see 60-65 mph gusts. Probably 55mph gusts further inland. Give or take I love wind, and all damage and surge aside, the wind with hurricane sandy was downright awesome. It was quite the scene Link to comment Share on other sites More sharing options...
earthlight Posted November 5, 2012 Share Posted November 5, 2012 I think we would need the Euro to "bomb out" a bit later so that we can fully take advantage of the dynamics, instead of having a storm with waning dynamics. But it was definitely a step in the right direction. Almost all of the guidance that have wrapped up solutions show the best jet dynamics/favorable environment for the most rapid strengthening to our south...so I think it's just something we're going to have to deal with unless the set up changes dramatically. This afternoon people were wondering why the models were showing a weird break/lightening of precipitation over our region...well the answer is the models are decaying the CCB and beginning occlusion .. so it's not all that far fetched. Link to comment Share on other sites More sharing options...
Dsnowx53 Posted November 5, 2012 Share Posted November 5, 2012 Almost all of the guidance that have wrapped up solutions show the best jet dynamics/favorable environment for the most rapid strengthening to our south...so I think it's just something we're going to have to deal with unless the set up changes dramatically. This afternoon people were wondering why the models were showing a weird break/lightening of precipitation over our region...well the answer is the models are decaying the CCB and beginning occlusion .. so it's not all that far fetched. That would also explain the 'funky' 850mb temp contours as well. Lightening precip = less evaporative cooling = more mid level warmth. And yeah I guess it's either a phase and the best dynamics going south, or no phase or a very late one and the storm missing/grazing. The former being much more likely, obviously. I haven't really studied the synoptic pattern as much to really determine if the storm bombing out at a latitude favorable for us is even possible, but I do tend to agree with you. Link to comment Share on other sites More sharing options...
Snow_Miser Posted November 5, 2012 Author Share Posted November 5, 2012 Not sure why, but the 06z GFS trended MUCH colder this model run towards the ECM. Pretty large amounts of CAD this model run. Could be because of a quicker and weaker system with less WAA and a stronger high to the north. I could definitely be wrong though. http://raleighwx.americanwx.com/models/gfs/06zgfs850mbTSLPp06_county066.gif Link to comment Share on other sites More sharing options...
FPizz Posted November 5, 2012 Share Posted November 5, 2012 What are the rain amounts? Link to comment Share on other sites More sharing options...
Weathergun Posted November 5, 2012 Share Posted November 5, 2012 That would also explain the 'funky' 850mb temp contours as well. Lightening precip = less evaporative cooling = more mid level warmth. And yeah I guess it's either a phase and the best dynamics going south, or no phase or a very late one and the storm missing/grazing. The former being much more likely, obviously. I haven't really studied the synoptic pattern as much to really determine if the storm bombing out at a latitude favorable for us is even possible, but I do tend to agree with you. I don’t think there is much chance it for continued deepening, at our latitude. By the time it reaches, Delmarva’s latitude, the flow is strengthening over the Northern Tier out West and a ridge is building over SE Canada. This forces the storm to cut-off from northern stream. So it’s looses its baraclinic support early on. This the cold air and energy source from the northern stream. This though, just has our bigger impact on our snow potential than our wind potential. It doesn’t make much difference if the low is 990mb or 980mb for pressure, Because with 1030mb+ high to north, we’ll still see a tight pressure gradient supporting gale or storm force winds. The only way we escape strong winds out of this, is if it’s goes far enough east. Link to comment Share on other sites More sharing options...
CooL Posted November 5, 2012 Share Posted November 5, 2012 If the gfs is right we could all see some wet snow. Can't believe how much colder it went Link to comment Share on other sites More sharing options...
NEG NAO Posted November 5, 2012 Share Posted November 5, 2012 These snow amounts on the GFS are wrong - in fact it is unlikely the metro will see 3 flakes - HIGHLY unlikely to see 3 plus inches http://raleighwx.ame...zgfssnow078.gif Link to comment Share on other sites More sharing options...
Weathergun Posted November 5, 2012 Share Posted November 5, 2012 The 6z GFS bombs out closer to us. Which is a big change from past runs. Link to comment Share on other sites More sharing options...
CooL Posted November 5, 2012 Share Posted November 5, 2012 The 6z GFS bombs out closer to us. Which is a big change from past runs. Yeah we get better dynamics with the deform band over us. I'm sure we'd get atleast some snow if the 6z gfs is right Link to comment Share on other sites More sharing options...
eduggs Posted November 5, 2012 Share Posted November 5, 2012 The 06z NAM had surface wetbulbs temps just above zero with most of the rest of the column at or below freezing for areas just N&W of the City around the time on precip onset Wed night. Early glance at the 12z NAM suggests a slightly faster, stronger, further west low center. I suspect it will also suggest the possibility of some frozen precip pretty far south and east. Link to comment Share on other sites More sharing options...
blizzardof09 Posted November 5, 2012 Share Posted November 5, 2012 even if we have incredible dynamics with this storm bombing i still cannot see how we can get alteast a trace of snow anywhere near the coast. four weeks later we'd be talking about our first winter storm, as of now i see this as coastal rain/wind and inland snowstorm. i wouldnt be expecting much more than that close to NYC metro Link to comment Share on other sites More sharing options...
eduggs Posted November 5, 2012 Share Posted November 5, 2012 The 12z NAM is likely frozen to start for most areas away from the immediate coast line. The surface temps, not surprisingly, are a little warm. But just inland and esp elevated areas would likely snow with that depiction. Link to comment Share on other sites More sharing options...
eduggs Posted November 5, 2012 Share Posted November 5, 2012 The 12z NAM is likely frozen to start for most areas away from the immediate coast line. The surface temps, not surprisingly, are a little warm. But just inland and esp elevated areas would likely snow with that depiction. Closer look at 57hr NAM sounding indicates you'd likely have to be west of the City (esp above 500ft) to get into the snow. But it's not far off and the intense precip has not arrived by that time period. Link to comment Share on other sites More sharing options...
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