wdrag

Record for CP on Monday the 18th. 63-1984. Did not check any others but think near record warmth possible midday before chilling in the evening,

There will be substantial impacts in parts of our area. Wet ground...gusts 40-50 trees slop over. Power outages again, this time I think more in NJ/CT/MA than back ion NYS/ne PA. Flooding rainfall for parts of the area. So unless the track slides west through PA, there will be plenty to observe Sunday-Monday. Not sure if anyone saw the EC 90 hours 525 5H low in Ohio. Swift changes ahead for Tuesday morning. In my mind,no doubt an active 3 days (Sun night-Tuesday).

Back to this two event system: Modeling seen through 06z/15. Looks like a narrow stripe of 4.5", 24 hour rainfall, along just west of the eventual track of the near STS (wherever that track ends up) mentioned in the post above..with amounts maybe near 1" in 50 MPH squalls eastern LI to 1.5-3" remainder of the NYC subforum. Ensembles (GEFS/NAEFS) seem to have as many streams into minor flood as last Sunday-Monday and a couple moderate (actual rain will determine). Monday morning Impact could be larger due than last week, since it dumps in a shorter time frame, IFFFF the rainfall mentioned above occurs Track looks fairly solid within 60 miles either side of NJ/Hud Valley. For now max rainfall axis somewhere near I95 VA-NJ, to adjust in future modeling. TT briefly near 50 Monday morning so isolated thunder possible. This is a negative tilt shortwave rolling newd from GMEX on this one. Note sure of records for Monday but 60s NYC? Regarding the second event: I am pretty sure I84 corridor will see some wet snow Tuesday morning-midday, and a rain-wet snow mix to the coast (no stick on coastal pavement). It's far into the future but when we toss all this Monday morning RH/warmth back into the Appalachians and then sharpen the 5h trough quite noticeably into PA by Tuesday morning, I have to think there will be a band of FGEN with deep unstable moist soundings to 600 MB crossing the region Tuesday, offering a 3-9 hour period of generated precip. Amounts probably under 1/3rd inch. Not impossible to see spotty 2-5" snow fall Poconos/Catskills/Adirondacks/Berks/Litchfield Hills with pavement treatments needed above 1000 feet. Even nw NJ hills to MA Worcester Hills could see a slight grass accumulation. Just too early to be confident except I am expecting a little snow in those areas-accums debatable and best to think less than 1" for now. Just too much leftover moisture in my opinion to not are wring it out as it turns colder. If the 5H trough doesn't sharpen (neutral 5H tilt as cyclically modeled) by the EPS and GEFS, then this second event won't happen. So for now, one event at a time. This first one I think will result in flood hazards (inland) and coastal flood (partly because of e-se inflow ahead of the trough, and partly because of lowered pressure (990 MB)... both probably minor but not impossible for spotty moderate. Timing and inflow determined.

Storm #1: added the 07z/14 NWS Blend of Models through 7PM Monday... a decent start at this long lead time.

Well, I sure hope the EPS change to stronger and slower this 00z/14 c cycle is correct. If so, we're in business Tue-Wed-Thu. Before that... Monday morning should be a little rough with wind gust 40, coastal flooding (minor?), a significant 6-12 hour dump if 1-3" which I think would produce some flooding, certainly impact early morning travel.

My take based on all primary models through 00z-06z/14: Sunday afternoon-next Thursday I84-I95 corridors (17th-21st), a large storm will produce heavy rains NJ-se NYS-LI-CT-MA by Monday morning (roughly 1-3"), then abate and temporarily be very mild Monday. Then the precip "possibly" redevelops Tuesday or Wednesday as a period of mixed ice or wet snow from NJ-PA northward to NYC-Boston. Snow accumulations will be elevation dependent (as usual)... for now, the ensemble snow accumulations (snow depth change) are small... generally under an inch in our area. Tue-Wed is fraught with uncertainty... does precip occur or not? If it does, then I have high confidence it would be wintry...just not sure if precip redevelops. Ensembles are spreading out the wintry stuff a little further south. EPS is much sharper with the trough here in NJ next Tuesday... that will be critical. If it's mushed out with wsw 5H flow instead of ssw flow, then part two is probably offshore. Just too uncertain for me to express confidence on part two. Also, am aware that part one Sunday night-Monday won't be a nor'easter but instead probably an inside runner. Basis for wintry is scrolling through "24 hours snow depth change" on CMCE, EPS, GEFS. Will check back Friday to see how this unfolds. (as some say, am a Modelologist- it isn't like it was 30-35 years ago when two model runs/day and couple models to monitor-dig into--- now it's speeding through many general model ideas, counting on model intelligence to lead me-us down the right path)

Just have to ride out all the model variations the next couple days. I think we'll settle in on a big Monday event, secondary Tuesday, and then ebyond that.... ?? I don't think the models are near consensus yet on how Noon Sunday-Tuesday plays though it looks very wet at times. I may not comment again til Friday afternoon. This is a good week to continue outdoor cleanup.

Another significant weather event is headed our way, about 7-8 days after the last. By the time the first day of winter officially starts, we may see a little snow or ice for the interior and substantial rainfall that could prompt flood and coastal flood statements for our area. Sunday-Thursday "potential pair" of wet events that could eventually change to ice or wet snow, especially I84 elevations Tuesday-Wednesday. Substantial rainfall is outlooked... probably at least an inch for virtually the entire NYC subforum and possibly """isolated 6"""" worst case. Not saying 6" will occur but it's in some of the advance modeling and it could end up over the fish. Persistent northeast winds for possibly up to 4-5 days could be a coastal flood problem. A disturbance in the southwest USA today-Wednesday 12/13 migrates east, ingesting short waves from the northern stream and a juicy one out of the Gulf of Mexico. Then it apparently plods northeast along the east coast. How close the upper low comes up here before fading east is with the traditional uncertainty and TBD, but it will be interesting to monitor. There could be a significant banding signal well to the northwest of the upper low and if that upper low holds together longer and eventually makes it up to the south of LI by the start of winter., it will have produced quite bit of impact here. That is still very uncertain and not a lock. Modeling seen through 06z/13: EC-EPS is basically one and done by late Tuesday, but it even flags interior snowfall, the GEFS is most robust for wintry weather and the CMCE, a slightly warmer model, also has some wintry stuff a little further north of I84. All ensembles agree on accumulations Adirondacks. This is another El Niño event, that is particularly juicy (see FL coast pressure intensity), and has a noticeable RRQ of the upper jet near the Canadian Maritimes (southern-northern stream merge) to assist upward motion. Will there be two events next week? or just one centered on Monday? Title update 6AM Saturday from the original that follows: added Damaging gusts LI/CT. A single or pair of nor'easters Noon Sun Dec 17, 2023 - Thu evening Dec 21. Potential: flooding rain I95 corridor, persistent gusty ne wind driven tidal flooding episodes next week, change to ice or snow interior elevations by Tue morning.

Good Wednesday morning... I'll probably start a thread around 9AM for the Sunday-Thursday "potential pair" of wet events that could eventually change to ice or wet snow to I84 Tuesday-Wednesday. Substantial rainfall is outlooked... probably at least an inch for virtually the entire NYC subforum and possibly isolated 6" worst case. Persistent northeast winds for possibly up to 4-5 days could be a coastal flood problem, but far too early to be sure.

Waiting til at least tomorrow morning before a thread start... my trying to be conservative at distant time with uncertainty on UA low track evolution, possibly a two part storm over 4 days, and how much of the area might get some snow?

Prepping for a likely (70% chance in my mind) topic issuing either this evening or Wednesday for the period late Sunday the 17th through Wednesday morning the 20th. Looks to me like a sizable nor-easter with marginally cold enough air (850 MB and surface temp ensembles) nearby to the north and northwest for snow potential at least down to the i84 corridor inclusive of nw NJ and maybe trickling down to the CT coast at the storms end. But the main story probably is rainfall potential... I've added the EPS probability of 1" or greater rain in 24 hours centered Monday the 18th. This event could put out isolated 4" rainfall for some part of our area. Wind gusts will be a concern but as most have noted, model guidance tends to be a touch high... still I would not rule out a wind hazard for the coast. For initiating this topic... prefer to give the ensembles at least another 12 - 24 hours to agree a little more and for the EPS to be consistent (GEFS-CMCE not quite as far west and that is my concern). No matter this southern system will be a big wet one for at least Texas, and probably the Gulf Coast, and in my opinion up the southeast coast to our area. Ensembles probably not holding on to the upper low long enough as we go into the middle of next week. This won't be a big deal if qpf remains at or below 1" and little or no snow... but potential exists for something significantly larger as a nor'easter. Compared to this past storm... way too early for me to express confidence one way or the other. Depends on eventual track of the upper low so I have to wait... it's about potential and I think this event will have plenty of interest up here in a few days. Can it get up here as per the EPS or does it get deflected out to sea?

I continue interested in a decent widespread weather event 17th-21st... if it all plays right, enough cold air to the north as short waves seem to be digging a little more across the northeast USA than modeled a few days ago (mid week and early this weekend) and that could leave the nw fringes interesting, as a large Southeast USA coastal storm heads northeast. Long long ways to go... We'll have to see if the GEFS loses its very nice late weekend-early next week 5H flow pattern.

Maybe so... for now, jury out on specific rain impact on Bronx building collapse all over NY media this evening. Very good lead time by NWS on flood watches... I know it wasn't major river impact but nevertheless... a sizable rainfall event.

Finding out ore as we go. 2.5" 900' in Stillwater NJ, High Point was 5" at 1500. eastern Sussex County high terrain did not do as well as the western part of our Sussex County. Probably related to FGEN position as checked through the HREF.

Two CoCoRaHs sampler rainfall maps and one snowfall for the NYC subforum. Please click for clarity. The only element that didn't pan out was the wind... also. note that there are power outages affecting areas with seemingly combined 4+" snowfall and decent wind gusts shaking the wet snow off the branches (and probably breaking them). It looks to me like everything ab over 1000 feet picked up an inch or more of snow with the break point on Trace snow mush covering deck, maybe somewhere between 500 and 800 feet MSL.

Possibly worthwhile to monitor Sunday(17th)-Thursday (21st) of next week. Something looks to be coming and it may again be marginally cold enough... embedded within a general warmer than normal period. I'll add a sampler of snow and rain totals on the Dec 10-11 thread.

No changes to add. Enjoy the storm. Suggest for observations add only rainfall above 2", wind gusts 45 MPH or higher, power outages, downed tree limbs, unusual flooding, and any snow-sleet accumulations A good multi faceted storm and travel will be impacted. Brunt still 5P-5A. I may not be posting between 945A-7P.

Looking at just about everything I can...I would now follow the HRRR, RGEM, 12KM NAM closely, realizing the RGEM and HRRR can run a degree or two warm, affecting ptype and snowdepth. Also HRRR wind gusts can be 5 MPH too strong. Right now they are less than the EC which has 50-60 E LI on the 18z/9 cycle. I'd keep the door open for grass snow acc near I95 including metro NYC. How much on pavement and snow boards is questionable. Not saying this will happen but I think it likely there is at least a mix of sleet-snow for an hour or two 8A-Noon Monday. Will check back at 645A Sunday. Have a good night.

I may not be able to add anything to this until tonight. Everything is more or less the same. Am a little doubtful of 50+ wind but it could happen. The snow seems to be getting closer to NYC and I can see an inch or two elevations of southeast NYS/nw NJ but it melts fairly fast after 8AM Monday. At least we know Nino is producing.

Please follow all current and future NWS watches, Warnings and statements. This thread can serve as the one stop shop for both forum participant expectations and observations. Already as of Friday afternoon December 8, flood related watches have been issued for a wide area centered on the I-95 corridor with wind damage potential expected to lie east of I95, excepting possibly in isolated severe thunderstorms later Sunday. Wet snowfall accumulations could slow travel in the Poconos northeastward Midnight to Noon Monday morning. 19Z/8 December Blend of Models snowfall and and rainfall through Monday has been added to show some of the basis of the watches/concerns. Wind guidance has decreased during the past couple of days as the cold front and associated low pressure system drift across the NYC subforum late Sunday and intensifies a little slower. GEFS 18z/8 wind guidance for 50KT gusts as seen through Polar Wx is less than 40% for the eastern tip of LI. This lower wind expectation may also limit coastal flooding to more of a minor event. No matter, there is time for the models to adjust the expected results. So we have an event...not sure how serious but it will impact travel over our area. Continue monitoring the models, including ensembles and of course NWS products. 820P/8 At 851AM Monday December 11 posted review data. The wind did not work out on 50 knots gusts. The rain and snow did. So far, I've seen about 20 streams or thereabouts from southern New England to Philly to either be or forecast to go into minor flood, and one or 2 may go to moderate. Power outages were mostly NYS and ne PA where wet 31-33F snowfall exceeded 4" and wind gusts may have added to power outages. High Point NJ had 5" at 1500'. Modeling was overall good... especially the elevation dependent clarity on positive added snowfall. 19/

At 8PM I probably will start a thread on the storm based on the watches already posted. Need some more time to digest the ensembles and add my primary concern. Til later, Walt

Based on 00z ensembles and op cycles, not going with a thread. Nice rain storm with wind gusts 55-65 MPH e LI-coastal eastern New England. So power outages-damage drama, if any, restricted to a small part of the geography population for the NYC subforum. Backside CAA w-nw gusts probably NYC subforum widespread 40-45 MPH Monday after sunrise. I see the continuing slower-colder-bolder 06z/8 NAM but not quite buying into it, however It does highlight for me, the potential for as much power outages-tree damage in elevation related 4-8" snowfall swath expanding new from a small segment of ne PA to the Adirondacks Monday morning as compared to e LI-coastal New England power outage gusts. Added the 00z/8 EPS snow depth change. Blend of Models is similar. Not the worst storm we'll see this winter but worthy of monitoring for travel etc.

Not starting a thread for this yet... however, per GFS/EC --am pretty sure scattered wind gusts 10 Mph higher than what I see here for LI-CT (55-60). Primary reason for no thread is that affected population (mainly e LI/CT River eastward) and max gusts look a little southeast of I95. I did see the 18z NAM and EC are slowing a little. This I think is a good sign for more action but will reconfirm (or not) Friday morning 630AM. I see by the time 850 Jet develops to e LI, speed is up to 85 knots. That's a good sign despite neutral lapse rate. This weenie is satisfied with two days of spotty measurable snow in the NYC subforum higher elevations.

You should get a period of light snow or flurries midday. Interesting that one major channel in NYC had no mention of snow this morning in their forecast for today, the others did. Interesting if they have another model that dries it all out? HRRR continues to bring it on into NYC as of the 11z cycle.

Am not starting a 55-65 MPH wind threat thread for Sunday night yet... not a lock despite GFS amping up a bit on 06z/7 cycle..the EPS is down a little bit from yesterday and the Canadian is routine. I don't want to post a thread for only eastern LI verification where I'm pretty sure we'll see a 1-4 hour period of these 55-65 MPH gusts. SVR threat still lingers coastal NJ-LI. Would rather have a good look at this around 730PM tonight inclusive of ensembles etc. Have a day including forenoon-midday flurries with measurable just west of NYC though roads just wet where a little measurable.