Thunder Road Posted March 22, 2011 Share Posted March 22, 2011 Rather tight gradient as TTN "only" sees 0.80" but much colder, as only 0.13" of that falls as IP, the other 0.67" the column is below frz up to 700mb. 0.36" of the total precip falls with 2m temps of 33.0 or less. Link to comment Share on other sites More sharing options...
NaoPos Posted March 22, 2011 Share Posted March 22, 2011 Still on the southern side of guidance here with the nam. Not getting too excited yet. Link to comment Share on other sites More sharing options...
LocoAko Posted March 22, 2011 Share Posted March 22, 2011 Just checked 00Z NAM Bufkit for New Brunswick. 2m temperatures are in the low-to-mid-30s and 0.67" QPF falls as snow (a little IP mixed in) although it is forecastin to accumulate to a total of 5.0". Seems marginal but just barely doable. The 0C isotherm hovers around 500 feet before crashing to entirely below freezing by 03Z Wednesday. Link to comment Share on other sites More sharing options...
LocoAko Posted March 22, 2011 Share Posted March 22, 2011 Just checked PNE and TNN ... a general 4-5" for them as well with a brief period of mixing Wednesday afternoon and early evening. Link to comment Share on other sites More sharing options...
atownwxwatcher Posted March 22, 2011 Share Posted March 22, 2011 00z RGEM @ 48 Link to comment Share on other sites More sharing options...
isnice Posted March 22, 2011 Share Posted March 22, 2011 00z RGEM @ 48 That's too warm; the low is too far north. We need it to slide off the coast around the southern tip of the Delmarva. Link to comment Share on other sites More sharing options...
Thunder Road Posted March 22, 2011 Share Posted March 22, 2011 00z RGEM @ 48 way to Link to comment Share on other sites More sharing options...
atownwxwatcher Posted March 22, 2011 Share Posted March 22, 2011 Snow to rain verbatim Link to comment Share on other sites More sharing options...
NortheastPAWx Posted March 22, 2011 Share Posted March 22, 2011 ... I'll take it. Link to comment Share on other sites More sharing options...
Thunder Road Posted March 22, 2011 Share Posted March 22, 2011 GFS shows no change from 18z through hr42. So far the NAM is still a southern outlier, but its consistency is haunting. Link to comment Share on other sites More sharing options...
Yes_Probably_Maybe_No Posted March 22, 2011 Share Posted March 22, 2011 GFS shows no change from 18z through hr42. So far the NAM is still a southern outlier, but its consistency is haunting. all by itself...pretty much expecting a cold rain here Link to comment Share on other sites More sharing options...
atownwxwatcher Posted March 22, 2011 Share Posted March 22, 2011 HPC ALTHOUGH THE NAM HAS TRENDED SOUTHWARD/WEAKER ALOFT OVER ITS PASTDAY OF RUNS...ITS SURFACE LOW HAS TRENDED NORTHWARD/STRONGERACROSS THE MIDWEST YET RETAINS GOOD CONTINUITY FROM INDIANAEASTWARD. THE ECMWF HAS SHOWN REASONABLE CONTINUITY WITH THISSYSTEM OVER ITS PAST COUPLE DAYS OF RUNS. WHEN COMPARING THEGUIDANCE...BY LATE WEDNESDAY AND EARLY THURSDAY THE 18Z GFS ANDRELATED 18Z GEFS MEMBERS LIE ON THE NORTH SIDE OF THE OVERALLDETERMINISTIC/ENSEMBLE DISTRIBUTION. SINCE THERE IS NO TREND INTHIS DIRECTION...WILL FAVOR A COMPROMISE OF THE NON-18ZGFS/NON-18Z GEFS MEAN GUIDANCE HERE WHICH IS IN VERY GOODAGREEMENT AND IS PART OF THE LARGER CONSENSUS. Link to comment Share on other sites More sharing options...
famartin Posted March 22, 2011 Share Posted March 22, 2011 GFS and EC surface temps are pretty warm (at least around TTN)... would be mostly rain with perhaps a period of mixing/wet snow which might accumulate a small amount. Not impressed by the NAM as its all by itself. Link to comment Share on other sites More sharing options...
mattinpa Posted March 22, 2011 Share Posted March 22, 2011 GFS and EC surface temps are pretty warm (at least around TTN)... would be mostly rain with perhaps a period of mixing/wet snow which might accumulate a small amount. Not impressed by the NAM as its all by itself. GFS by far has the most northern track, though - EC temps can be a bit warm. I think we can see a couple inches, but I'm most interested in down the road a bit. Link to comment Share on other sites More sharing options...
Voyager Posted March 22, 2011 Share Posted March 22, 2011 Winter Storm Watches up for most of NEPA. Link to comment Share on other sites More sharing options...
phlwx Posted March 22, 2011 Share Posted March 22, 2011 ...and in the Lehigh Valley as well. :axe: Link to comment Share on other sites More sharing options...
phlwx Posted March 22, 2011 Share Posted March 22, 2011 FWIW, NWS is riding the NAM hardcore. Can't even say they're riding the Euro since the Euro is not as cold as the NAM and is (at least in terms of surface profile) closer to the GFS than the NAM. Link to comment Share on other sites More sharing options...
MGorse Posted March 22, 2011 Share Posted March 22, 2011 FWIW, NWS is riding the NAM hardcore. Can't even say they're riding the Euro since the Euro is not as cold as the NAM and is (at least in terms of surface profile) closer to the GFS than the NAM. For reference from our AFD... FOR THE UPCOMING WINTER WEATHER EVENT...THE NAM/ECMWF MODEL SUITE WAS CHOSEN FOR THE TEMPLATE. THE GFS HAS BEEN TOO WARM/TOO FAST FOR A FEW DAYS NOW. Link to comment Share on other sites More sharing options...
Thunder Road Posted March 22, 2011 Share Posted March 22, 2011 Both the NMM and ARW want to keep this an all-snow event through 48 hrs, with the NMM colder (as to be expected). Notice on both of them, however, that between 30 and 33 the 850mb temps crash south. On the ARW, watch the sim radar dry up between 33 and 36. I think this really indicates the potential for dry air and evap cooling to screw things up in some way or another. That said, 38.9°/38 here right now, lol. The NMM prints out 0.75"-1.50" while the ARW is generally around 0.25" Link to comment Share on other sites More sharing options...
Parsley Posted March 22, 2011 Share Posted March 22, 2011 Definetely an interesting 24-48 hours on tap. From what I gather, most models give eastern PA (north of the PA Turnpike) a few slushy inches overnight into tomorrow morning. If precip. and cold air lingers longer, especially farther north across eastern PA, higher totals could occur. The NAM is just crazy, if that ever ended being right, Wow! Link to comment Share on other sites More sharing options...
am19psu Posted March 22, 2011 Share Posted March 22, 2011 Definetely an interesting 24-48 hours on tap. From what I gather, most models give eastern PA (north of the PA Turnpike) a few slushy inches overnight into tomorrow morning. If precip. and cold air lingers longer, especially farther north across eastern PA, higher totals could occur. The NAM is just crazy, if that ever ended being right, Wow! That sounds about right. South of the turnpike could start as sleet tomorrow then quickly changeover to rain. It'll be interesting to see where the southern extent of the accumulating snow sets up. Looks something like a TTN-DYL-RDG line. Link to comment Share on other sites More sharing options...
ptb127 Posted March 22, 2011 Share Posted March 22, 2011 Voyager - looks like a disgusting 4-8" snow, according to the point and click forecast from NWS.. Overdone?? Link to comment Share on other sites More sharing options...
Parsley Posted March 22, 2011 Share Posted March 22, 2011 That sounds about right. South of the turnpike could start as sleet tomorrow then quickly changeover to rain. It'll be interesting to see where the southern extent of the accumulating snow sets up. Looks something like a TTN-DYL-RDG line. I would think, for the snow lovers across southeastern PA, the arrival time of the precipitation lends additional hope to a period of snow (atleast a small amount) accumulating before the sun comes up through the clouds tomorrow. Maybe the colder air holds out just long enough near or just south of the Turnpike as well. As usual, it wlll be a close call. Link to comment Share on other sites More sharing options...
phlwx Posted March 22, 2011 Share Posted March 22, 2011 For reference from our AFD... FOR THE UPCOMING WINTER WEATHER EVENT...THE NAM/ECMWF MODEL SUITE WAS CHOSEN FOR THE TEMPLATE. THE GFS HAS BEEN TOO WARM/TOO FAST FOR A FEW DAYS NOW. I don't mean to pick nits with the NWS but I guess I don't get where the Euro is in line with the NAM at the surface or at 850...it's certainly quite a bit warmer than the NAM at both the surface and aloft and at best a compromise at 850 between the GFS and NAM. Just my humble opinion. I don't necessarily agree that the Euro is completely in the colder camp based on what it's showing. The NAM may very well be right in this but I don't think including the Euro is really that accurate since the Euro doesn't show, IMO, the same or similar solution. Link to comment Share on other sites More sharing options...
tombo82685 Posted March 22, 2011 Share Posted March 22, 2011 mt holly snowfall map...pretty elevation dependent closer to philly Link to comment Share on other sites More sharing options...
phlwx Posted March 22, 2011 Share Posted March 22, 2011 FWIW, from the NWS (Tony) JUST WANTED TO ADD A QUICK AND DIRTY VERIFICATION OF WHICH MODEL IS HANDLING OUR UPCOMING SYSTEM THE BEST THROUGH ITS 12HR FORECAST. OVERALL ITS THE ECMWF. THE NAM'S SFC LOW FCST POSN IS TOO FAR SOUTH AND ITS TOO COLD, IT HAS INFERRED FREEZING RAIN AS A PTYPE WHERE TEMPERATURES ARE IN THE MID 30S IN SOUTH DAKOTA. CONVERSELY THE GFS HAD A DECENT PTYPE AND SFC LOW VERIFICATION, BUT ITS QPF AXIS VERIFIED TOO FAR TO THE SW IN THE OH VALLEY. BOTH CANADIAN MODELS PUT THE SFC LOW TOO DEEP INTO THE COLD AIR. WE'LL SEE HOW THE MODELS INITIALIZE OFF THE 12Z SOUNDINGS. Link to comment Share on other sites More sharing options...
Thunder Road Posted March 22, 2011 Share Posted March 22, 2011 It looks like the NAM is finally "warming up" to the idea of mainly rain in Philly (Sorry I couldn't resist the pun) Besides a little bit of sleet at the onset, this is over for people south of 202. Higher elevations will probably still cash in though. I could see parts of Chester County getting 4 or 5 inches of snow while Philly sees a Trace. Link to comment Share on other sites More sharing options...
iceman56 Posted March 22, 2011 Share Posted March 22, 2011 mt holly snowfall map...pretty elevation dependent closer to philly Liking that 5" line near me in NW Chesco which is mainly above 700'. Link to comment Share on other sites More sharing options...
Thunder Road Posted March 22, 2011 Share Posted March 22, 2011 NAM still has a burst of snow at the end for all in PA (and yes Ray, TTN too) Comapre 00z hr 54 to 12z hr 42, look at the northern expanse of precip just disappear. Cue wining from PSUHazleton The 850mb frz line shifted a good deal north, however, which is probably an accurate trend since it's closer to what the globals have been shwoing for some time now. Link to comment Share on other sites More sharing options...
Parsley Posted March 22, 2011 Share Posted March 22, 2011 12z NAM....is......umm...........a mess? I don't even know what to say about it. Elevations over 500' still looks snowy though. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.