wdrag

Good Saturday morning everyone, It's a forum but I think those who malign the models would be nowhere had their been no models. For this forum I hope a respectful approach is preferred (at least I hope that is preferred by our moderators). Each weather situation is different and we'll see at Noon Monday which model or blend of models verified most accurately at their portrayal of an elevation dependent event. Tuesday CoCoRaHs)post of snowfall, maybe sooner if WFO's need to issue PNS's. I did not substantially change the thread title this morning. A slight delay and smoothing out of the date-day and added OBS. I95 to the coast wet roads, despite any wet snow at the front and back end of this moderate elevation dependent I84 northward snow event with potential for power outages north of I84 in 4+" wet snow areas near 1000 feet and above. Modeling suggests bands (yes newd transitory banding) of heavy qpf tomorrow morning that between 8AM and Noon could be mixed with wet snow down to I78 and NYC (no accum or spotty 0.1" grass) for NYC-LI. Back side of the event is in question but some of the modeling is continuing to drag its heels in storm departure (and was at thread inception). I think the implication is the remaining 5H vort-sharp trough passing eastward across NJ will send a cluster of showery mixed r/s newd from BWI_PHI at dawn Monday and try to merge-blend in with the 850MB nose of the northeast jet band in NYS/CT around sunrise in NYC to bring periods of wet melting snow to I95 and LI. This too may come down briefly 3/4Mile in parts of NJ/NYC-LI Monday morning-midday with a whitening of the grass and snowboards possible. I think we have a major test between ensemble (and operational) positive snow depth change and the NBE snowfall when modeled 2m temps are 33-36F. I may be misunderstanding the use of positive snow growth, especially in the ensembles... for now I use positive snow growth as a useful tool for roads... and double it for a base to max range of measurable snow. When it snows, temps tend to drop to between 32-34F an hour or 2 after it starts.--not sure if modeling can capture that. Obviously at night its an easier accum on all surfaces. Cooler air is now leaking ever so slowly south down to I90 and will be drawn into the BL over our area from northeast during this event while strong lift from the approaching 5H short wave and 850MB se inflow will help cool the column Sunday before backside comma head curls southward and eastward of our area Monday morning. My 530AM expectations for NNJ remain as is: Northern NJ-Poconos -southeast NYS Sunday-Sunday night: GREAT UNCERTAINTY with vastly differing modeling for an elevation dependent event and much more conservative NWS forecast (see their graphic attached). 1/2-2" wet snow Easton PA-Warren County and the south two thirds of Sussex County (including Newton) over to Kinnelon but 3-6" wet snow likely Poconos and the north border of Sussex County including High Point, Vernon and northern Wantage locations above about 1000 feet as well as Orange County NY elevations above 1000 ft. Rain changes to a 3 hour period of heavy wet snow sometime near 8-9AM Sunday then either quits in the afternoon or back to rain. Sunday night periods of mixed precip changes to lighter wet snow during the night. Temps fall during the snow Sunday to 32-34F Suggest factor in possible delays into the Poconos - I84 itself. Manageable mostly wet road travel Easton PA to Newton and Kinnelon NJ but slushy slippery at times elevations above 1000 feet. Not all modeling agrees but plan for the worst and it may turn out much less hazardous than I expect if the NWS much more conservative snow forecast is correct (see their graphic). This forecast is slightly less impact than what I was thinking on previous daily issuances. I'll check back in tonight or tomorrow morning. Have a day and fingers crossed that everyone realizes most snow events NYC-LI tend to be minor. I'm pretty sure you'll see a little white rain as some say tomorrow and some minor accum Monday.

I'll update the headline around 10A to include OBS and any other possible minimizing considerations. Pretty big banding signal front end Sunday morning with heavier rain mixing very briefly with wet snow NYC I80 and possibly changing to a period of heavy wet snow for 3 hours late Sunday morning on snow ratios way down. More at about 10A.

sighhh...just doesn't look so boring to me 2/2, 2/5-7 and then the Southern Stream should crank several storms mid and end of the month (after the 10th). Differs from some of the modeling suggesting a dryer than normal first two weeks of Feb.

Maybe it will verify, and we need to watch NAM (so called bad model) trends remain with the thermal structure that its 06z/26 modeled for I80 north. FWIW( same poster 10 to 1 too high) but the 06z/26 EPS chance of 1" of snow (make it 1/2" at a temp of 32-33F non pavement). Front end Sunday morning may surprise. Pretty big lift from se inflow jet that is cooling the thermal structure. Gradient is subject to nil snowfall in NJ but the core that skirts MPO-FWN northward deserved a little more snow, I thought. Surface temps marginal for acc, especially roads along and s of I80. In the hills---drive carefully. Will revisit tomorrow morning as have family and work and at that time, I'll adjust the headline to include OBS.

ELEVATION dependent. Valleys: roads wet, grass etc slushy. I think if we get above 1000 feet, it should look much more interesting and an interesting ride along the NYT (I87), I84, I91 valleys looking vertically Monday morning.

GREAT uncertainty: See the much more. conservative attached 5AM NWS deterministic snowfall forecast that is the basis of their forecasts issued early today. I went much heavier elevation dependent. I could be crushingly wrong. Yet, I feel the need to provide guidance and certainly plan for myself with grandkids in the Poconos and many friends here. Also attached NWS ensemble chance of 1 and 4". The icing chance is not attached for Saturday-Sunday but that is also a factor for at least N CT-MA higher terrain. My expectation: Two to 8" wet snow likely elevation dependent I84 corridor. Uncertainty exists on when rain changes to mostly wet snow on Sunday and how much. Elevations above 1000 feet have the best chance of exceeding 4" (Poconos, northern Sussex County into Orange County-Litchfield Hills). Meanwhile, Newton in southern Sussex County down into Warren County and east to Kinnelon NJ and back into the Easton PA-Phillipsburg NJ area maybe only get an inch of slushy snow with manageable travel and roads wet during the day Sunday. Temps during the snow Sunday 32-34F with occasional melting on pavement at all elevations. Suggest factor in possible delays into the Poconos - I84 itself with best accumulations before sunrise Sunday and after sunset Sunday evening. Power outage problems may develop whereever 4+" of snow accumulates. Not all modeling agrees but plan for the worst and it may turn out much less hazardous than I expect.

NBE nice starting point for NYC - we'll see again but am not too confident they're reading in nearly enough snowfall terrain north of I80. It would be a colossal bust for the EPS if this does not occur and I'm starting to see some problems in the NBE as I look closely at event after event. It's a starting point. Still have a few more cycles of modeling for a slight change in everything we're seeing. My hope is the 00z/26 GGEM is following the 18z RGEM southward expansion of snow, to nearly what it was a day ago. Just not sure about the EPS but it is fairly ominous for pockets of power problems I84 high terrain. Sooner or later it has to back down or other modeling has to come up.

Still a lot of confusion on what to believe, but the EC and EPS from 18z/25 have struck down the north idea, are much faster with change to wet snow and definitely fit the thread outlined. Whether we can muster any accum NYC/LI is very uncertain- but I think the I84 corridor is the place to be...terrain above 1000 feet. Basically the EPS/EC has smoothed out its messy 12z op cycle and says much faster for change to 32-33F wet snow, with melting on pavement during the daylight hours but a problem hazardous event at times. Going to need a hazard advisory of some sort. We're only 48-60 hours from starting. Also 4+ at 32-33F could initiate a few isolated power outages by 11PM Sunday within 15 miles of I84 and terrain above 1000 feet.

Anyway, that's what I will monitor.

On colder air: think we need to watch what happens in MA tomorrow night-Friday as there is some NAM signal on some BL CAA. If it doesn't depart, it could be easier to turn over to snow. EPS has a small chance of ice in the transition over the I84 hills.

CMCE-EPS 12z ensembles make the 12z op's look pretty inaccurate. They are further south with snow-- and probably a little flatter than the 00z-06z/25. I haven't looked in detail but those of us who have pivotal can do a 06z-12z compare on snow depth change and prob for 1" and draw your own conclusions. My guess is the 00z/26 GGGEM (Canadian) will be colder and snowier sooner and the 12z EC OP throwing a narrow swath of 6+ in the hills of nwNJ into se NYS looked suspicious along with the early quit. Either solution is part of a myriad of outcomes and suggest using a smoother ensemble approach. The model message (I think): discontinuous - disorganized indicators, possibly related to the upper air structure. I can't conclude what that will look like but uncertainty prevails on snowfall and imo need to wait some more. Back tonight or tomorrow morning.

WPC take on 1/4" ice/snow water equiv. Dark green is the primary threat region. 12z Canadian moving north for one cycle and hopefully slips back south but now it's a GEFS/EPS consistency split on probs. Canadian move is not what I wanted to see. LI best chc wet sloppy snow 12-18z Monday with comma head enhancement rolling eswd through LI and probably lots of pavement melting=wet roads. Question on timing most of the snow I84 should be Sunday night-Monday morning.

Snuck in for a moment... I even think Feb 4-8 something sizable AVL-BOS. Temps as usual this winter marginal but something I think is going to have emerge from the south up the coast.

NYC-LI..please take what you can get out of this. The Feb thread was started...where there may be a little more hope (kick the can?). Primary big snow is favored north-northwest fringe of the subforum. Something to track and see how it evolves. NYC still in the mix for 1/2-2" tail end back side--slushy.

Power outage problems may develop in the red colored area of the attached 4+" chance. Note those chances are higher than what we posted yesterday. Not all modeling agrees with this but think it wise to plan for this but all models are increasingly concerned since 24 hours ago. Banding possible up in the I84 corridor... Agreed snow ratios. NYC-LI...not threaded more than 1/2-2" (slop) Offline til tonight or Fri AM. Try to keep NYC in some sort of snow mix the last 25% of the storm.

February thread started.

Added the 1/18 CPC FEBRUARY outlook and the new CPC week 3-4 issued 1/26. Both posted here on 1/26 748PM. While the anomalies are warmer than normal the first two weeks of February, it might not mean absurdly warm preventing snow in NYC. The warmer than normal anomalies seem to be more centered up in Canada, modifying the potential for true arctic intrusions down here. Guidance suggests the potential for several east coast storms In February and the possibility of snows from Asheville to Boston - I95 westward. That may be climo combined with the El Nino pattern of potentially above normal precip southern USA and up the east coast to NYC. So, can the NYC CP Feb snow total exceed our January total? Temperatures may chill down a bit in mid February? Will add on here Friday evening the 26th with the new 1/26 CPC guidance. May also add Don's stats if he has any for this pattern for Feb. Thank you all. And now the CPC Jan 31 update for Feb. Looks a little higher prob of not so much qpf, and chilled New England a bit. On March 2 attached the Feb verification. Looks like our local take verified OK with the mid month chilling, and twice the Jan paltry snow total at CP. and the CPC trend to below normal qpf also worked out with east coast events trailing off the coast south of our area.

Agree. Probably not good to buy in, instead disorganized lesser approach that I’d WOC D5 winter wx which has 30-49% chc 3+ only hills I 80 north. I can’t post it as am remote. I may not be back til tomorrow morning. It’s early to buy big. Keep it minimal unless stats suggest otherwise

Ensembles smooth out the drama. We want the ensembles to keep us in the mix as we get closer to Sunday

The thread was started at 930 AM and comments about Sunday should go into that thread. That’s what it’s for. Thanks. Am on the road

A short wave currently dropping sewd from the Pacific Northwest dives down into the Four Corners region Friday then lifts out into mid Atlantic states Sunday. Five day in advance graphics are posted including the EPS which has been steadiest and slipping slightly south as we draw closer to the weekend. Please read the labels. Most are 24 hours that end Sunday night...the EPS the fastest. The three global models for chance of 1" or more are attached, the EPS for 4+ which has been the highest and most cohesive for the past couple of days and I added the EPS 850MB wind field to show nose of the jet potential enhancement of precipitation Sunday night. Mild air in advance of the system will probably mean rain or melting of the wet snow at the start early Sunday, but by Sunday night, it should be cold enough for even untreated pavement accumulations down to I78, of course dependent on snow occurring. A period of ice is possible in the anticipated interior transition to snow--especially hills. Cold air flowing southward Monday on gusty winds will probably mean freezing up of whatever slush and possible early Monday delays. Uncertainties prevail - including track-flattening-weaker-stronger etc, but think this is worthy of monitoring for a minor-low impact event NYC and a potential light-moderate snow event for the interior from eastern PA across NNJ se NYS CT. 933 AM Saturday 1/27/24: Changed title to smooth out dates, add OBS, and delay ending of seeing snow til at least midday Monday. Comments on these changes on the last page (p6) to this moment.

Thank you. Moving forward now... I will thread Sunday-Sunday night sometime this evening around 9PM (grandkids). Increasing chances of 1/2-2" NYC-LI and for about 4+ nw NJ-I84 corridor. Not major but 850 low and increasing ne 850 MB Jet by 06z/Monday makes this a favorable outcome. Jut want a look at 12z ENS... no doubt in my mind at least a bit of snow coming to NYC and shovel able WET snow nw NJ-CT with initial melting but surface CAA makes this a candidate for deteriorating untreated pavement conditions Sunday evening -night.

Monitoring Sunday 1/28: EPS is the most organized and consistent. It's axis has slipped a little to the south, painting this as an elevations based wet snow of 4+" potential along I84. EPS confidence is 30-45%. However, think we have a small less than 1" accum down to I95 with refreeze of slush Monday morning. NYC prob for 1" is still very low, so no thread but monitoring trends the next day or so. Attached EPS prob for 1" Sunday. It says be cautious about thinking 1" NYC CP. By the way: there was a little sleet mixed with the rain last night in the NYC-LI area.

Sunday EPS chance of 1" and 4" wet snow, elevations heaviest. Gets pretty cold Monday morning and slush freezes. Confidence on 4+ by the models is not high

Wantage NJ rain-sleet-snow mix. back deck trying to get slick at 32.5F.