Doorman Posted February 4, 2014 Share Posted February 4, 2014 PROBABILISTIC HEAVY SNOW AND ICING DISCUSSIONNWS WEATHER PREDICTION CENTER COLLEGE PARK MD456 PM EST MON FEB 03 2014VALID 00Z TUE FEB 04 2014 - 00Z FRI FEB 07 2014 ..MIDWEST TO NEW ENGLAND...THE WINTER STORM CONTINUES TO SLIDE EASTWARD TUE NIGHT INTOWEDNESDAY AS THE ASSOCIATED UPPER TROUGH BROADENS/SHEARS SOME INTOA CONFLUENT FLOW DOWNSTREAM. HOWEVER...A POWERFUL UPPER JET WITHCOUPLED DIVERGENT MAXIMA ALOFT AND INTENSE WARM/MOIST TRANSPORTFROM THE SOUTH WILL BE OCCURRING AHEAD OF THE COLD FRONT. SOME OFTHIS MOISTURE WILL WRAP INTO THE CIRCULATION AND BACK INTO THECOLD AIR WHICH SHOULD HELP TO SUPPORT HEAVY SNOW FROM NERN OHIOINTO CNTRL/SRN NEW YORK INTO CNTRL NEW ENGLAND. WHILE STILL A DAY2 FORECAST...THE MODELS ARE TRYING TO PLACE AN AXIS FOR A HEAVYFRONTOGENETIC SNOW BAND SOMEWHERE IN THE OHIO VALLEY EXTENDINGEASTWARD...MOST NOTED IN THE 12Z NAM. HOWEVER...THE NAM APPEAREDTO BE TOO FAR NORTH WITH ITS SURFACE LOW AND 850-700 MB FRONTSGIVEN STRONGER CONSENSUS TO BE SOUTH...ROUGHLY 50 MILES SOUTH OFTHE NAM. THIS CHANGES SOMEWHAT BY THE TIME THE STORM REACHES NEWENGLAND HOWEVER...WITH THE GEFS MEAN NORTH OF THE GFS WITH ITSHEAVY QPF AXIS...WHILE THE ECMWF AGREES WITH THE GEFS/EC MEAN ANDOTHER NON-NCEP GUIDANCE. STILL..THE NAM APPEARS TOO FAR NORTH WITHTHE INITIAL LOW WEST OF THE APPALACHIANS AND SECONDARY SURFACE LOWFORECAST TO REDEVELOP OFF OF THE NEW ENGLAND COAST. GIVEN OUTPUTIN THE SREF MEAN OF 10-12 INCHES OVER NEW YORK AND QPF HEAVYENOUGH TO SUPPORT 12+ INCHES FROM THE DETERMINISTICGUIDANCE...FEEL CONFIDENT ON THE POTENTIAL FOR FOOT+ TOTALS ACROSSA SIZABLE PORTION OF THE NORTHEAST ON WEDNESDAY. TO THESOUTH...INITIALLY SUB-FREEZING TEMPS EAST OF THE APPALACHIANSSHOULD SUPPORT THE INITIAL P-TYPE AS SNOW/ICE. HOWEVER...STRONGSOUTHERLY FLOW IS EXPECTED TO QUICKLY ALLOW A TRANSITION TOPL/FZRA MIX AND THEN RAIN. POCKETS OF COLDER AIR NEAR THEAPPALACHIANS MAY BE HARDER TO SCOUR OUT WHERE HIGHER PROBABILITIESOF 0.25 INCHES ICE ARE FORECAST. SECONDARY LOW DEVELOPMENT NEARTHE COAST AND A TRACK JUST INSIDE OF THE 40N/70W BENCHMARK SHOULDKEEP COASTAL LOCATIONS AS MOSTLY WET...BUT A BRIEF CHANGEOVER TOSNOW ON THE TAIL END OF THE DEPARTING PRECIPITATION SHIELD http://www.wpc.ncep.noaa.gov/discussions/hpcdiscussions.php?disc=qpfhsd http://www.wpc.ncep.noaa.gov/wwd/winter_wx.shtml#lows Link to comment Share on other sites More sharing options...
PB GFI Posted February 4, 2014 Share Posted February 4, 2014 At 36 hours, but the simulated radar shows the heaviest synoptic precipitation is over then. Thank you. Link to comment Share on other sites More sharing options...
96blizz Posted February 4, 2014 Share Posted February 4, 2014 Check it out.. 30 hours hires_t850_fire_31.png 33 hours hires_t850_fire_34.png Cool graphics! Link to comment Share on other sites More sharing options...
earthlight Posted February 4, 2014 Share Posted February 4, 2014 Link to comment Share on other sites More sharing options...
96blizz Posted February 4, 2014 Share Posted February 4, 2014 Check it out.. 30 hours hires_t850_fire_31.png 33 hours hires_t850_fire_34.png Parts of Monmouth County drop 6 in 3 hours ---really? Link to comment Share on other sites More sharing options...
+SNfreak21 Posted February 4, 2014 Share Posted February 4, 2014 The 4km NAM is all IP/ZR on E-wall for NYC, so what is that snow map above indicate? Sleet? Link to comment Share on other sites More sharing options...
earthlight Posted February 4, 2014 Share Posted February 4, 2014 The 4km NAM is all IP/ZR on E-wall for NYC, so what is that snow map above indicate? Sleet? Well sleet counts as snow on these maps a lot of the time. But also the firewx nest is run at a higher resolution of 1.333 km. Link to comment Share on other sites More sharing options...
PB GFI Posted February 4, 2014 Share Posted February 4, 2014 The high RES is 30 - 32 max in MC Throughout . KNYC is 28- 30 max . Link to comment Share on other sites More sharing options...
user13 Posted February 4, 2014 Share Posted February 4, 2014 Check it out.. 30 hours hires_t850_fire_31.png 33 hours hires_t850_fire_34.png Its interesting that the 850s go north of nyc when the heavier precip moves out, now the question in my head is if the heavier precip develops further south or last longer, how much longer would the 850s hold south of nyc Link to comment Share on other sites More sharing options...
Northwest NJ Posted February 4, 2014 Share Posted February 4, 2014 The NAM appears to be a warm outlier. The RGEM has snow prior to a changeover for the greater NYC area. The ECMWF and GFS are both colder. While I don't believe the NAM can be outright dismissed, I suspect odds favor more snowfall than what the NAM is depicting. The 0z RGEM, GFS and ECMWF will be interesting. Upton also considers the NAM an outlier. SOME FLUCTUATION BETWEEN MODELS OF THE POSITION OF THE LOW. SOME LIKE THE NAM...ARE MORE NORTH WITH THE LOW WHILE THE GFS...ECMWF...AND CMC ARE FURTHER SOUTH. NAM AND ITS TEMPERATURES ARE GOING TO BE ON THE WARMER SIDE AND WILL NOT BE USED AS MUCH AS OTHER MODELS CONCERNING THE FORECAST. Link to comment Share on other sites More sharing options...
Mikehobbyst Posted February 4, 2014 Share Posted February 4, 2014 My guess is 6-8 inches of snow and .40 inch ZR accretion for south shore LI. The models show 30 degrees as the highest temp during the event. Could be worse icing for south LI since 1/1994. A very serious situation for LI looks 80-90 percent likely ..... Imagine a 26-30 inch blizzard next Monday on top of that.... 1 in 200 year type stuff.... Link to comment Share on other sites More sharing options...
TWCCraig Posted February 4, 2014 Share Posted February 4, 2014 My guess is 6-8 inches of snow and .40 inch ZR accretion for south shore LI. The models show 30 degrees as the highest temp during the event. Could be worse icing for south LI since 1/1994. A very serious situation for LI looks 80-90 percent likely. This is looking like a serious snow and ice storm....... Imagine a 26-30 inch blizzard next Monday on top of that.... 1 in 200 year type stuff.... I thinking more like 4-6" with about 0.20" ZR and about half an inch of sleet, 0.15" of rain if it gets above freezing. Link to comment Share on other sites More sharing options...
REDMK6GLI Posted February 4, 2014 Share Posted February 4, 2014 My guess is 6-8 inches of snow and .40 inch ZR accretion for south shore LI. The models show 30 degrees as the highest temp during the event. Could be worse icing for south LI since 1/1994. A very serious situation for LI looks 80-90 percent likely. This is looking like a serious snow and ice storm....... Imagine a 26-30 inch blizzard next Monday on top of that.... 1 in 200 year type stuff.... This may be the first reasonable post from you. Except the 1994 ice storm comparison, the weekend however everybody may be talking those amounts if this storm does indeed take a BM track as a Miller A Link to comment Share on other sites More sharing options...
jm1220 Posted February 4, 2014 Share Posted February 4, 2014 The snowcover throughout the area should help in keeping surface temps cold along with the NE wind direction. I'm starting to think a lot of us won't get above 32. Maybe I will briefly, but hopefully by then a lot of the snow/precip has fallen. Link to comment Share on other sites More sharing options...
jm1220 Posted February 4, 2014 Share Posted February 4, 2014 I thinking more like 4-6" with about 0.20" ZR and about half an inch of sleet, 0.15" of rain if it gets above freezing. I'm hoping that the snow comes in heavy right away and either dynamically cools the atmosphere like the NAM shows or is colder overall like the other guidance. That would probably get us to the 4-6" in a few hours or so, and then the changeovers start. The question fr us mostly will be whether or not the surface warms up. I'd say 50-50 we never get above 32 when there's much precip falling. Link to comment Share on other sites More sharing options...
Zir0b Posted February 4, 2014 Share Posted February 4, 2014 Bet precip gets in faster than expected as always with these SW flow events, and we dryslot before the temperatures either at the surface or mid levels get too warm. Betting 65-75% qpf falls as snow and the rest sleet and minimal freezing rain. Link to comment Share on other sites More sharing options...
mranger48 Posted February 4, 2014 Share Posted February 4, 2014 Won't we dry slot pretty good after the initial slug (after 12z) in this situation between the primary and the secondary? Sent from my iPhone Link to comment Share on other sites More sharing options...
IntenseBlizzard2014 Posted February 4, 2014 Share Posted February 4, 2014 Won't we dry slot pretty good after the initial slug (after 12z) in this situation between the primary and the secondary? Sent from my iPhone No way. We are too close to the developing Secondary SLP to be concerned about that. Link to comment Share on other sites More sharing options...
Rjay Posted February 4, 2014 Share Posted February 4, 2014 Won't we dry slot pretty good after the initial slug (after 12z) in this situation between the primary and the secondary? Sent from my iPhone If the secondary forms further north then yes, otherwise no. Link to comment Share on other sites More sharing options...
SnowGoose69 Posted February 4, 2014 Share Posted February 4, 2014 RGEM turns NYC and even a bit north to rain 14z or so but snow arrives about 04z and shows the snow line staying sandy hook south til 10z or so, so colder again, it may continue trending colder beyond 12z as time goes on Link to comment Share on other sites More sharing options...
earthlight Posted February 4, 2014 Share Posted February 4, 2014 RGEM looks a hair warmer compared to the 12z run. Link to comment Share on other sites More sharing options...
earthlight Posted February 4, 2014 Share Posted February 4, 2014 RGEM turns NYC and even a bit north to rain 14z or so but snow arrives about 04z and shows the snow line staying sandy hook south til 10z or so, so colder again, it may continue trending colder beyond 12z as time goes on From the crappy graphics I have it looked like it ticked warmer at 36 hrs..but I haven't seen more than that yet. Link to comment Share on other sites More sharing options...
SnowGoose69 Posted February 4, 2014 Share Posted February 4, 2014 RGEM looks a hair warmer compared to the 12z run. I think it was warmer in southern areas and after 12z but it seemed colder from 06-12z on Ptype Link to comment Share on other sites More sharing options...
earthlight Posted February 4, 2014 Share Posted February 4, 2014 I think it was warmer in southern areas and after 12z but it seemed colder from 06-12z on Ptype The total snow graphics definitely cut back by a few millimeters Link to comment Share on other sites More sharing options...
IntenseBlizzard2014 Posted February 4, 2014 Share Posted February 4, 2014 The total snow graphics definitely cut back by a few millimeters SN_000-048_0000-2.gif Prolonged FRZ? Link to comment Share on other sites More sharing options...
96blizz Posted February 4, 2014 Share Posted February 4, 2014 FWIW, the GFS already looks colder than the NAM at 27 (no surprise). Link to comment Share on other sites More sharing options...
+SNfreak21 Posted February 4, 2014 Share Posted February 4, 2014 Its less snow for NYC, but the cutoff is not as extreme in CNJ Link to comment Share on other sites More sharing options...
earthlight Posted February 4, 2014 Share Posted February 4, 2014 Prolonged FRZ? Yes over the interior Link to comment Share on other sites More sharing options...
SnowGoose69 Posted February 4, 2014 Share Posted February 4, 2014 The RGEM almost attempts to plaster us with frozen precip than nearly dry slot us right after, that would make the snowpack depth crew happy Link to comment Share on other sites More sharing options...
WintersGrasp Posted February 4, 2014 Share Posted February 4, 2014 The RGEM almost attempts to plaster us with frozen precip than nearly dry slot us right after, that would make the snowpack depth crew happy I'm down with that. Would love to hold on to 4-5 inches by the time the weekend storm hits. About 6" on the ground now, expecting 3-4 more before freezing rain Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.