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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.

As noted above 00z/4 EC and UK are much weaker or nothing. For now, take that with a grain of salt. BUT, does tell us that uncertainty continues large and prepare for less than desired. I checked the 00z/4 NAEFS and it's still on board-the bigger concern I have is the marginal thickness. I can see sleet/freezing rain as more of a problem than snow. 03z/4 WPC probs for significant snow/.ice remain the same, but that is without the toned down EPS. I sure hope the EC/EPS comes back in the next few cycles, otherwise have to think wasted thread.

Have not threaded a wind event for Monday the 6th, but fwiw... ensembles have basically a 50 knot sw flow over us Monday. How strong the CAA in the evening is somewhat uncertain. Will rereview the next several days for a shorter fuse wind advisory thread if needed.

Many models have a little snow or ice for our area next Wednesday the 8th, possibly ending as rain? WPC Friday afternoons forecast has a half inch+ of qpf for our area next Wednesday and a 30-49% chance of 3+" of snow or 1/4 inch combined sleet/snow. Click the graphics. That's not too bad for a day5-6 forecast. I may have overreached on PROBABLE hazardous???? I do think there should be a little ice, at a minimum over the I84 high terrain. The rest of the area much more uncertain. We should be close to the right rear quad of an upper level jet core centered near Nova Scotia (130 knots 200-300MB) next Wednesday (see EPS 18z Wednesday 300MB), this behind the strong negative tilt short wave departure of Monday. A weakening 500MB short wave from the upper Midwest Wednesday morning crosses into northern New England by Thursday morning. The 850 Low is north of our area. Snow thicknesses are marginal especially south of I84, so that snow amounts this far in advance are VERY uncertain and likely to be less than 3" rather than more. Some sort of light to possibly moderate ice-snow event should occur in parts of our interior Wednesday Dec 8. One consideration is the qpf being less than currently advertised which would reduce amounts. This thread is posted to focus anyone's interest into the discussion. LI-coastal NJ--- primary modeling may eventually favor your area but for now, I think the primary ensemble considerations for a 6 to 18 hour period of hazardous wintry weather next Wednesday is to the northwest of I95. TAGS and Thread title may change this weekend or early next week. 717PM/3 Dec 2021 6AM Wednesday the 8th: converted this thread to OBS-Nowcast. No other change.

Nevertheless, it is of interest for a portion of our area which should get at least some ice or snow, especially nw of I95, particularly I84 corridor. Lots of options... working up a simple thread that posts by 715P. This is not a promise of snow acc but I am thinking a winter weather advisory event is possible for a portion of our area.... VERY early, especially thread the needle but too many models wants a little ice or snow.

No threads from me regarding a possible wind event Monday afternoon-evening. GFS strongest on this but no consensus for a widespread 40+ knot event. Ditto Wed snow ice I84 corridor: The 06z/3 GFS shows us how variable the solutions for the 8th. 00z/3 EPS-GEFS cyclically continue to favor some snow or ice I84 corridor but the snow may be biased high by the standard 10 to 1 ratio applied to mixed precip. Just too early to be confident of much snow (probably would be a quick change to ice or rain), so at this time, I'll wait til this evening to rereview for consensus on this wintry hazard. Others have mentioned the same. Attached the ~04z/3 WPC ensemble guidance for a 3"+ snow event or 1/4" mixed frozen on D6 (Wed the 8th). Their probs of under 29% for our area on a D6 forecast justifies, for me, no thread at this time. Just need to be patient, shop and get some more outdoor cleanup completed, and/or put the finishing touches on the holiday lighting-preparations.

38 MPH gust at 841PM in Wantage NJ. Awaiting on threads for the 6th and 8th for more consensus. Too close to being ordinary. Hope EC is right but little worried when consensus is lacking.

Posted the snow amounts for that event in NOV thread. Ditto over 1000ft nw NJ for board accum.