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Depending on future modeling I may begin an OBS-NOWCAST thread for I80 north Friday evening: for a little mixed freezing precip starting Saturday morning trending to freezing rain high terrain north of I84. Maybe extreme n CT gets lucky and picks up an inch or 2 of snow-sleet Saturday, but I 84 itself should be 1/2" or less of any frozen, even if it ends as light snow Sunday morning. If the models drop extreme nw NJ and even LI from the icing mix at the start, then I'll refrain from a thread and all the obs can be tucked into the nw suburbs. Just a late start to winter.

Good Thursday morning everyone, It is Dec 16. I'll follow up this post Friday morning...for hazardous high terrain ice Saturday, especially the morning along and north of I84 from the Poconos through extreme northern Sussexn County NJ to the hills of CT and much of Massachusetts. The attached graphic shows the chance of icing-see the legend for your area. It's just a heads up for some 'possible' untreated surfaces slippery travel for a few hours. Maybe a scenario of mixed sleet/snow to start, changing to freezing rain for a while. Most of the snow threat is extreme northern CT northward. Have a good day. Walt

So attention is on the Plains-Midwest. Understandably. Locally, not threading the coming weekend event along or just n of I84 due to membership being fewer up there but may start posting on nw suburbs thread tomorrow or Friday. EC keeps chilly air along the I84 corridor while all other models much less so. Could be a winter wx advisory event up there Saturday afternoon into early Sunday for sleet/zr- maybe even a little snow, possibly ending as rain (hilly terrain especially). Again, I do have some concern about the EC being too cool. 09z/15 SREF is not as cool and more like the somewhat milder GFS. So the 11/28 and 12/8 threads while minimalist snow, at least were something, compared to what winter elements we've had since, and sort of what it looks like for a while longer (to me: no future multi model agreed snow dates for the NYC area, at least not yet). I like the -NAO but not sure it will be enough to give us much more than what we enjoyed 11/28 (-NAO) and 12/8 (neutral NAO). What i want to see is some southern streamers get drawn newd into the -NAO pattern. So far, seems difficult.

The following locations experienced 40 knot or greater winds generally near or after squall line passage. HPN 41 POU 40 EWR 41 Below: Anemometer heights may not meet NWS criteria in NJ Brick IN NY Bayville 50 Eatons Neck 62 Great Gull 44 Bannerman Inland 41 (Hud Rvr) Jones Beach 46 Great S Bay 44 Fire Island 40 East Moriches 41` Shinnecock Light 45

Adding on: I expect that more data verification will have to be added to local storm reports today. I just saw two reports of 50 knots nw LI via Weatherflow, also lower Hudson Valley a number of reports around 40 knots. Staffing may be a reason why the data has yet to post. I can list the stations if needed. 544A/12

While not all the data is in as of this 536 AM Dec 12 writing, our area basically didn't have advisory criteria. Squall line was less focused than I would have wanted (narrower line with spotty high reflectivity), possibly cut off by the Delmarva line that had developed earlier around 6P. There is some spotty power outages in our area, most of it northern and western fringe near I84. Definitely not the magnitude of a couple of early Dec events. Meanwhile north of I90... good luck with the recovery, especially northern NYS. Ditto our tornado ravaged mid Miss Valley-lower Ohio Valley region.

Everyone has noticed the spotty lightning from the Catskills to NNJ since 830AM.?

I am dropping the following on the forum: Let's see what happens. This includes a new tool I will reference in the future... Imperfect but it coalesces some of the finer high resolution guidance into a general solution for forecaster applications (Neural Networks). 1) 12z/11 3K NAM position of the squall line at 10PM. 2-3) Neural Network (NN) info 4) NN prob of severe today 5) NN prob of 50 KT gust 6) NN timing of event within 2 hours. 7) 12z HRRR 2-5K max updraft helicity. Suggests my earlier concern for TOR was too far north. Overall I may be an hour fast on the more ing timing. Nothing else to share.

So OKX and BOX joined the wind advisory previously issued a day ago by Mt Holly. SPC has no change from yesterday in it's outlook. A squall -fine line of briefly heavy showers is continuing to be modeled by the HRRR as of 5AM this morning with the primary time frames for passage roughly 7-830PM ne PA, 8P-930P NJ/se NYS, 9-11P CT-NYC, 11P-1A BOS-E LI. Modeling continues as posted yesterday... This is the same system that has caused all the fatalities upstream in the Ohio Valley, but in lesser severity here. Not impossible to see a TOR central NJ approaching NYC this eve, per HRRR 2-5KM helicity but probability quite low as of early this morning. There are some parameters that will need to monitored for increasing their values in future modeling for this to become a greater risk. I will probably be off line at times today, though I'll monitor-especially this evening to see what occurs.

Good Friday morning everyone, A consistently modeled 970s MB low moving into southeast Canada later Saturday will develop a strong low level 55-70 knot 850MB southwest jet ahead of it and a period of 50 knot west-northwest dry cold advection 850 MB winds behind it. A dying squall line is possible with the cold frontal passage Saturday evening. SPC has a D2 marginal risk for severe. Much of the guidance has near 45 MPH wind gusts for a fairly large portion of our area along the front with potential for pockets of 50-65 MPH gusts accompanying the squall line (could be just heavy showers and no thunder). This event should be a little more widespread than the previous two early December events. Mount Holly already has a wind advisory posted from 1PM Sat-1AM Sun. In advance, there could be isolated gusts 45+MPH during the afternoon in rather warm southwest flow but the main show should be with and just after the cold frontal passage-gust front during the early night, beginning over the Poconos around 6PM and sweeping east of the Twin Forks by around midnight. At least spotty tree-powerline damage should occur. Courtesy to the the NWS and Pivatol Weather for their graphics (SPC D2 outlook) and the (ECMWF sounding near LGA at squall line passage - a bit isothermal in the boundary layer which is a possible hindrance to transfer). Title: added OBS-NOWCAST in front of the previous title at 636AM 12/11/21.

I'm counting on all our long range specialists to not bury ourselves in short term ugliness and be unable to extricate later during the winter. I'm seeing the gamut of no winter, to more favorable winter opportunities after Christmas or January. I don't know, except we'll probably need something to jar the pattern into something that will be a broader snowy impact along and north of I80. Meanwhile, am holding off on a wind thread for Saturday afternoon-early night. Will check SPC D2 tomorrow morning, as well as HRRR/NAM. Many models have near or greater 64kt at 850MB in the Saturday afternoon WAA and 50+kt in the evening CAA. Both a little stronger wind fields aloft than what has occurred in our last two minimal wind events of early Dec. I'll want to be a little more certain of momentem transfer, so will try and figure it out early Friday.

The gist of the snowfall yesterday is in this CoCoRaHs map. Not shown are the icy conditions that followed after clearing set in during the night with subfreezing temps. Just about everyone had measurable melted w.e. as per the latter two maps. Click each for clarity. CP 0.04 includes T wet snow. You be the judge of the modeling and results of the original modeling prompt. Not a whiff but less qpf/snowfall than desired but the general idea was there well in advance. Best short term modeling was the HRRR and HRRRX followed by RGEM/SPC HREF, NAM 12k (NAM 3k was far too conservative). Not sure what the GFS was thinking from start to finish.

Likely starting a thread at 6PM for the 4P-midnight time frame Saturday DEC 11 for scattered wind gusts 40-55Knots and embedded potential severe thunderstorms. Here is SPC Day 3 with marginal risk up into NJ. Have a day.

CP 34F with 2.5MI all snow. 0.04" melted so far this eve. .. probably not measurable there yet.

Many have their location under the member .. I'll hunt if needed but wish it was all easy. Thanks for tip. Wantage NJ 0.4" final (heaviest of the season so far, all in 3 hrs)..still a few flurries but essentially done. Everything covered except pave wet. 29.3F. Dewpoint still 28 so maybe we get one more band (BGM band on radar now at 820PM??) before it's all done and dry air advection ends the potential. METAR: KNYC [New York/Central Par] METAR: KNYC 090104Z AUTO 30005KT 6SM -RA BR BKN014 OVC022 02/00 A2991 RMK AO2 SNB0058E02 P0001 T00220000 Note the 4 min of snow in the NYC obs above. Thanks all for your obs.-pix. I'm probably done for the night.

A couple of days ago modeling offered a potential rain to snow event for the 12th. No longer. But a thread may still be needed soon for damaging wind Saturday evening. Right now I'll go with modeling being a little over amped. We have had a couple of small scale wind events the past week with CFP's. This looks a little more potent but I think waiting a bit longer is useful. 12z/8 EPS has 64kt at 850MB on the WAA sw flow in the afternoon and 50KT+ on the CAA evening WNW flow. 18z GEFS is about 55-60KT on the sw flow and 45-50kt on westerly CAA.

I can never tell where some members are located, but thanks for the reports. Wantage NJ still snowing with 1/4" covering everything at 655PM and 30/28. Calm wind. SB around 515PM. Pavement wet. My perspective... while NYC probably does not see snow accumulations, it may see a rain snow mix by 830PM. CT is probably going to see widespread 0.5-1.5" snowfall by the time this ends, heaviest in high terrain, near or above 1000 ft where slippery spots can be expected on all untreated surfaces. The reason there are 9 pages on a low (not no impact) event (wet roads, reduced visibility briefly to 1 mile or less, at night) is that there hasn't been much noteworthy so far this season and probably won't be til at least the 21st. Let's accept what we get and we'll move on tomorrow. I'll try to get a CoCoRaHs snowfall summary posted tomorrow at 5P (after work). As far as modeling goes: NAM OK, 3KNAM far too conservative. HPC HREF decent. The best since yesterday has been the HRRR and HRRRX. RGEM not too far behind. GFS: not good. First days in advance way too amped, then too suppressed recently. One event, but a little concern for GFS.

So, the 00z/8 EC-09z/8 HRRR in particular are indicating that the negative tilt trough will light up with some light precipitation across our area, at times late this morning, ending early tonight. Least chance for seeing any whitening of the ground is NJ (I80 south) and most of LI where surface temps will probably cause melting. Follow the models/obs/radar developments and your own takes for this developing FGEN related precip, supported by the oncoming sharpening negative tilt trough that may develop an inverted trough back from the offshore low pressure to LI. Whatever occurs, it's all done by around midnight.

Good Tuesday morning everyone, Well when I initially saw the NAM and GFS from 00z/06z/7 I almost threw in the towel and and my perception could still be a WHIFF (swing and miss), but I'm continuing as yesterday. Short range modeling from the SPC SREF, SPC HREF, HRRR, EC/RGEM continue with a period of snow for much of the area. My guess the least chance is south of I80 in NJ. How much, probably not much if any accumulation but I'm hanging on. Whether this evolves with SPC modeled timing or HRRR/EC, or not at all..I can't be sure. For those complaining about modeling: If it was real good--we would not be still trying to figure out the reality in advance. and our AMWX chat would be a little different and possibly much less. So I probably won't comment further on this til this time tomorrow...you'll have all the model data to debate and slam. The uncertainty is large. The 500MB trough going negative as it passes by here tomorrow warrants further review of guidance as it comes in today-tonight. Late developer...may favor mostly e LI e CT northeastward for accumulative snow. IF the EC drops it, ditto HRRR/RGEM, then it's probably ballgame over. To me, it still looks like several hours of snow Wednesday (the 8th), beginning during the morning drive time and ending by dark. The Boston area to eastern CT snowfall is probably confined to between Noon-midnight. Amounts most areas from Hartford-Scranton including northwest NJ under 1 inch-some spots just one tenth of an inch (one tenth of an inch is miniscule), but untreated surfaces will be slippery for a short time Wednesday morning over the high terrain. For eastern CT to the Boston area, there could be a somewhat more significant snowfall of 1-2". This should not be a big deal but may require a bit of caution for some of us that need to be on the road. I added a graphic showing the chance of more than 1" of snow. Those chances have increased considerably for CT/MA, since we posted yesterday. The legend may of help. I also the SPC SREF mean and ensemble meters from the 03z/7 cycle for LGA. Click the graphic for greater clarity. --- So - I guess it will just be mood snow or flurries for many? Your call.

Before we get there (real warm weather): am not doing anything with this... GFS probably too amped, but 12/12-early 13 may also eventually need a winter thread. Would like to see Wednesday done before looking too far ahead.

Also fwiw: and we'll see what happens with the Wed eve reality check, but the 12z/6 GGEM continues edging north. We'll see what happens.

Not changing anything yet in Thread headline and TAGS. Will probably wait til 6A Tuesday... am with extended family this evening. Which also brings up the potential for 45 MPH gusts this evening with the CFP. For now no thread, but we ?MAY? have an SPS event for iso gust 45-50 MPH. Something similar to a few days ago (tho less thunder). I do see spotty small hail possible with this line as it gets into LI/CT via the HRRR. TT don't seem very large so the chance is pretty small. Also stability winds are marginal for transfer of >45 MPH. Glad there is still snow modeled for us.

Good morning, Still early: Reminder (except if someone has later information), but the NAM stops, I think in 2023, when it's positives are woven into other modeling. Here is the 12z cycle 3K NAM Ferrier 3K NAM 12K NAM all have been favoring e LI and se CT for 2+" of snow for most of the recent cycles. Click for detail. ALSO, I like to use positive snow depth change as my baseline. Now a matter of integrating with other models, a poor mans ensemble, so to speak.

I think we're all going to see a little snow Wednesday, some places maybe a little more than an inch. Probably no big deal on TREATED pavements- especially NYC and much of LI, but jury out on snowfall rates. What follows is my opinion expressed to a FB group of friends on what seems to be coming. I'll let this idle, hopefully for 24 hours and reconsider tomorrow morning, not wanting to pitch and roll with every model nuance. Good Monday morning everyone, It's Dec 6 and what follows is nothing major, but a caution from Baltimore northward to I84. Will detail a little more tomorrow. Before what could be a rather mild period during mid-month, we've got to get there. Looks like several hours of snow Wednesday (the 8th), beginning during the morning drive time and ending by dark; Boston probably confined to between Noon-9PM. Amounts most areas generally an inch or less, but untreated surfaces will be slippery for a little while Wednesday morning. This mood snow should be a little more than what most of us have experienced this season and might require slowing down a bit. I added a graphic showing the chance of morethan 1" of snow...for now it's not a big chance (less than 30%). There could be a short period of ice or light snow for the I84 corridor Friday morning the 10th. Posted 607A/6

Excellent considerations and we should see what happens. I do find it very difficult to believe the 00z/4 EC nada p and therefore it's tame EPS. To me, the WAA pattern induced after the 00z/7 CFP for 12z/8 should do the trick for qpf. Learning time... I tend to favor the EC inside 6 days, though I'm aware it's far from perfect...just tending to be a little better than the GFS. I like the idea of regional scores and also scores at the surface or at least 850MB (wind, temp) ... that's where it counts but of course resources and capabilities may be too meager to attempt.