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Can't comment too much on how things will transpire. These are chaotic model runs. I looked at the 12z/17 ensembles, and this 500MB trough maximizes all its weather over New England-our area and then weakens eastward. It seems a little bit progressive...not closing off deep (slow) enough. Yet the progressive EC has -33C over us at 500MB around Tue night-Wed morning. That warm water along our shores should be a player in the deepening process - lapse rates. Will check back Thursday morning.

Yes, plenty to monitor.

Yep... the images posted show how touchy the pattern is to flow patterns, exampling the EC OP as relative outlier when compared to ensembles. If the models do not trend west from here (06z/17) by this weekend, then it's a more or less typical Nov storm with backside flurries to the city, and scattered wind gusts 40-55KT on the backside, but not the bombogenesis HIGH impact portrayal for our area that was advertised a day or two ago. I still think upper lows are trouble and this needs to be monitored for an eventual slightly further southwest and stronger sub 980MB trend into southeast New England. Just my 2c, have no science to back up my concern...just my visual impressions and knowledge of previous guidance.

Good Wednesday morning everyone, Models having trouble with this coming pair of events, but the trend to slowing and coming back for the GFS and GGEM may have started with these 00z-06z/17 cycles. Too early to wave the white flag and surrender to the too far east, benign scenario. You've seen the 06Z GFS OP with flurries to LI and measurable north of I80. It's just one member of many. I am favoring the 00z/17 GEFS/GFS solutions over what I think are wayward east solutions for the 00z/17 EC/EPS. To describe the differences... the EC solution has a positive tilt to developments over the area 12z/23-Tuesday. See the 500MB flow pattern. It's an unlikely development, in light of the consistent signal of prior ensembles. Attached are the 00z/17 GFS OP 500MB, EC OP, EPS 500MB (tilted more neutral than it's single member OP, GEFS 500 [ignore the color difference-differing normalizing scheme], and the midnight WPC outlook for more than 3" of snow, basically Tue/Wed which confines the small (10-29%) ensemble chance of decent snow north of I84. Beyond For-Sat after Thanksgiving continues on the table for measurable snow closer to I95. It's in the favorable -NAO expectation. Thanks is extended to Pivotal Weather and US Weather and NOAA for these graphics.

Reviewed multiple models/ensembles through 18z/16. Suspect this eastward weaker day cycle modeling may be temporary. 12z/16 ENS for the GEFS continues to increase qpf here for the 23rd event, and 12z/16 EPS continues to wrap minor snow to the coast by Wednesday morning, If by Friday morning the 19th, models don't revert westward with a 970-980MB low northward from the e TIP of LI to e MA, then we probably avoid a widespread HIGH impact event. Both GEFS/EPS have a 500MB closed low aloft developing somewhere between ALB and BOS Tuesday. To get there the short wave has to dive southeast across PA then lift ENE from there. I could be wrong on this but I think the models will slowly return to a stronger greater impact storm for our NYC subforum northward. We should know by the 12z/19 cycle.

To stablilize the model differences , see if some sort of consistency develops via the GGEM=CMC. Gain have not seen 12z guidance.

If indeed there is a 965 mb low off our coast, it will be a national news story due to impact. That would be a weakening hurricane here. Have not seen any data since 11z and won’t till sometime this eve. I would think the size and strength of the previously modeled block combined with PAC Jet, out SST implies at least one major storm here. This presumes that block still occurs by Thanksgiving. Do not ignore 11/26-28 and maybe yet something thereafter. Will look at other TC posts for further consideration of impacts.

I agree. While 10 to 1 does not properly account for snow microphysics, melting, and mixed snow rain adding as all snow; it does suggest a consideration and is inclusive. None of the maps are perfect.

545AM/16: Title added HIGH to impact. Changed wind event to Damaging Wind. No other changes at this time. Bombogenesis with associated variable but high impact weather across the subforum. Wraparound snow potential continues for a portion of there subforum. Snow event, at least for the interior seems to be shaping up for the I84 region, sometime between the 26th-28th. Will rereview sometime this evening and again early Wednesday. I think the trend is a stormy Tuesday the 23rd, with lingering scattered wind gusts 40-50 kt early Wednesday then diminishing. EC OP seems to have a SVR signal for a short time and EC OP also has e LI pegged for 60kt gusts on the south wind as bombogenesis occurs. Thats' a 7 day single member model. Could easily shift to another area, especially into eastern New England. These coming events, pair of, should be monitored by travelers to consider options if stormy weather materializes. Certainly factor in the 'possibility' to need extra travel time.

726PM/15: Our forum is well aware that the recent few days of modeling is favoring a developing -NAO (Greenland Block-anomalously warm 500MB heights) that probably won't fully activate until Thanksgiving and beyond. One sharpening-negative tilt trough is multimodeled to drive southeast from central Canada Sunday the 21st and close off somewhere over New England Tuesday the 23rd, then possibly lodge near Labrador (50/50) Thanksgiving while following shortwaves try to organize a trough near the east coast by next weekend. The latter initially associated clipper low ??may??redevelop far enough south to become a significant impact player in our weather BY next weekend. For the past couple of days modeling has favored early next week (22-23) for a possible rapidly intensifying low pressure system somewhere along the mid Atlantic or New England coast. This event still has many undetermined outcomes (as of this Monday 11/15 writing), with the 12z/Monday Nov 15 EPS favoring wet weather (0.25-1.5" of rain) possibly ending as a period of wet snow or flurries even to the coast late Tue or Wed. That wetter and slightly colder solution is not yet shared by the 12z or 18z/15 GEFS, which has development later and further northeast. The NAEFS QPF is not very robust either. In fact I cant find any ensemble modeling with an 850 LOW south of Massachusetts. However, of interest beyond the probably quiet Thanksgiving day, is the likelihood of a little colder air in place ahead of the next strengthening short wave. Depending on how far south the core of that short wave (VORT MAX) tracks, it could permit coastal development near LI/Cape Cod late Friday. A long shot now, but the NAEFS as of the 12z/15 cycle has a bit more qpf for the NYC forum, especially CT, than for the earlier event. In summary, the bombogenesis near LI shown on recent GFS/EC OP models is of interest but it is not (yet?) the preferred ensembled solution...just a possibility. If it eventually occurs, the tags and title of this thread will update and reflect a much stormier scenario. The potential exists but far too early for me to express confidence (despite the anomalously warm SST's near our coasts that would energize sfc development). I am as interested what might happen next Friday-Saturday, with colder air in place and what at this issuance looks like an ordinary frontal passage, might develop into something with a bit of wintry interest, for the forum. If this becomes a non consideration in a few days, I'll admit it. 545AM/16: Title added HIGH to impact. Changed wind event to Damaging Wind. No other changes at this time. Bombogenesis with associated variable but high impact weather across the subforum. Wraparound snow potential continues for a portion of there subforum. Snow event, at least for the interior seems to be shaping up for the I84 region, sometime between the 26th-28th. Will rereview sometime this evening and again early Wednesday. Potent pattern for one or two travel HIGH impact events NYC subforum Thanksgiving week: Mon-early Wed 11/22-24; & Fri-Sun 11/26-28. 540AM/24: The above was the headline issued on the 15th, having added HIGH to impact and changed wind to damaging wind, Thread now refocuses headline on part TWO 26-28, w possible extension to 29 in the future. Part ONE failed due to modeling leading up to the 15th issuance being too deep aloft, too quick. Ended up further east and we were dry with a chill gusty wind. Tags: dropped heavy rain, and changed damaging wind to wind event. Modeling beginning with the cycles of Tuesday the 23rd have increasingly hinted at a possible wind advisory event for part of the area later Friday into Saturday morning followed by some sort of snow or flurry event Sunday - possibly lingering into Monday. Questionable outcome but we do know the modeling is digging a 3rd strong short wave trough into the northeast USA late this coming weekend. Therefore, while the first on the 23rd didn't produce hazardous weather, the second may generate a bit of a wind event in the wake of the cold frontal passage late this Friday, and the 3rd may allow some sort of coastal low to develop Sunday, departing Monday the 29th. Uncertainty exists.

Working up a cautious thread... very cautious. You may not like it but there is so much chatter about potential... I am liking after Thanks giving overall better. Will try to briefly explain in thread. Should post by 715P. Few if any graphics, just not enough consensus to hang my hat on.

Am remote seeing only your data but probably will carefully start a thread this evening.

Nice run... EC/CMC op's not there on the 06z/15 GFS op run, tho CMC strong. 06Z GEFS...no snow on the coast, tho that could be grid related. It's got snow to about I95...minor. Just not enough consensus for me...still looks too far N or too late for me via ensembles. That could change more favorably. Later, Walt

Yes, I see that (after my pre 06z/15 GFS op post). Not reacting to a single member (or few) D8 nice track-storm. 06Z GEFS will now have snow to the coast, I would presume, due to this member. Pattern just not what I can try to lock a scenario onto. I'll wait til this evening, if I do thread at that time.

00z/15 EPS has minor snow accumulations entire region Tue the 23rd. GEFS not. Am not quite as enamored with the evolving trough for early next week... hints of digging in too far north. Might be setting us up for Sunday-Monday 28th-29th but that also is not supported by ensemble low pressures. So, will wait awhile on any thread. Have a day.

https://en.wikipedia.org/wiki/November_1989_tornado_outbreak Check out the above: IF that's what we recorded in Nov 1989 (without doppler/without social media)... It happens... just more attention now with increased voracious media coverage through social media.

So, I know some others here have been talking about snow to the coast on the ensembles, in the previous few days for Thanksgiving week. It (like the period of the 12th-15th) is an impressive trough digging into the east next week (12z/14 multi ensembles) and seems to want to go negative. Also noting these shortwaves are ending up a little further west each run in an unstable flow pattern across the northern USA. IF this still looks reasonable in the 00z/15 multimodal ensembles, would start a thread tomorrow morning for the period 11/21-23 with 1" qpf, maybe iso max 4"?, or damaging wind (40-55kt coast), possible snow or flurries to the coast-favoring backside wraparound flurries. What further caught my eye is that it seems the NA block is more favorable (fully anchored) for a coastal storm sometime between the 26th-29th. By that time we'll know of the 21st-23rd storm develops a deep closed low heading toward 50N/50W.

We can probably benefit from normalizing.in the historic database. Tor Emergency first used 1999. Reports_ Concerted effort by NWS offices to verify warnings using all sorts of data sources, with social media contributions in recent years likely adding to the recent counts. TOR eval techniques improved, including use of building construction, and Doppler data to the strength values. Perspective-normalized would help.

Warming cycle of recent years-- and then yesterday, I think SST positive anomaly may have added a little juice-energy. Attached this mornings analysis.

NO thread, as yet, on inside runner (e Great Lakes) strong wind event around Nov 22-23.

Part doppler related, part greater comfort issuing.

Part Three: tonight and Monday. A band of showers will cross the subforum. Amounts generally light altho show intensity in some areas will be briefly (a few minutes) moderate or heavy. This showers will change to briefly minor accumulating wet snow terrain above 1000 feet in ne PA, extreme nw NJ, se NYS, nw CT. The showers will probably intensify as they cross eastern LI early Monday. Slight chance Thunder there. Monday... rather deep short wave crosses the area with scattered showers or sprinkles, except flurries I84 corridor higher terrain. Of interest is modeling attempting to generate thunder E LI Twin Forks newd, during midday. Three-Four Day CoCoRAHS rainfall totals will post Wednesday. (12th-15th stretch).

Excellent posts yesterday. I won't reiterate the SVR, except to say this 'potential' was modeled at least 36-48 hours in advance. HRRR Cape, lightning, hail, supercell composite. I have attached Part ONE rainfall of the 3 embedded event of the large eastern USA trough. Click for greater clarity. I'll add part TWO later this morning and the two day totals.

Sting Jet: Usually with bombogenesis, especially extreme. Our satellite from midday yesterday on. Compare with sting jet satellite second link below. https://www.star.nesdis.noaa.gov/GOES/sector_band.php?sat=G16&sector=ne&band=GEOCOLOR&length=240&dim=1 https://cimss.ssec.wisc.edu/satellite-blog/archives/26650 Wikipedia probably has a pretty good set of info and schematics-composites. https://en.wikipedia.org/wiki/Sting_jet#/media/File:European_Windstorm_Conceptual_Model.jpg Yesterday was considerable instability with southerly low level flow of moisture advection associated with the second of the strong short waves rotating newd through the ne USA grabbing some of the strong winds aloft. When we get a sting jet (100 MPH swath south side of a bombogenesis cyclone), a rare occurrence here, we won't like it. BIGGGG damage.

Should be very large hail just northwest Wananque NJ where DVIL over 40.