Potent pattern for part TWO being an impact event NYC subforum Thanksgiving weekend: Fri-Sun 11/26-28.

[wdrag]

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.

 

[Rtd208]

[wdrag]

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. 

[MJO812]

Euro and CMC 

[LibertyBell]

24 minutes ago, MJO812 said:

Euro and CMC 

so this is a storm thats supposed to happen before Thanksgiving or the day after?

 

[MJO812]

12 minutes ago, LibertyBell said:

so this is a storm thats supposed to happen before Thanksgiving or the day after?

 

Before but long ways out

[MJO812]

I see PSV is back giving people weenie tags

[hudsonvalley21]

36 minutes ago, MJO812 said:

Euro and CMC 

Subject to change of course, but definitely eye candy.

[hudsonvalley21]

4 minutes ago, MJO812 said:

I see PSV is back giving people weenie tags

So it begins  

[LibertyBell]

6 minutes ago, MJO812 said:

I see PSV is back giving people weenie tags

I'm going to be in the Poconos for Thanksgiving so I need to know days in advance what the weather will be like,.

 

[RippleEffect]

i love the tracking part, the next few days are going to be fun. i'm hoping we get a nice slushy inch at least.

[gravitylover]

Not looking forward to a round trip to Brockport on Mon/Tues if this comes together.

[CIK62]

Control says you can get to Grandma's Place-----but you can't get back home.    Lol!     Previous run had 0", so guess what the next output will show!!!???       12Z is down to 2" both ways.     Keep Tryin' GFS, you'll get it right.

 

[psv88]

2 hours ago, MJO812 said:

Euro and CMC 

Posting 10 day clown maps will always get you a weenie tag, on every single weather board

[uncle W]

I was thinking of 1971 as an analog?...

11 24 1971.gif.crdownload

[MJO812]

12 minutes ago, psv88 said:

Posting 10 day clown maps will always get you a weenie tag, on every single weather board

It's a weather forum right? It's not about posting the maps. It's about pattern recognition and the pattern is about to get better as we head into late month. 

[LibertyBell]

4 minutes ago, uncle W said:

I was thinking of 1971 as an analog?...

11 24 1971.gif.crdownload 85.71 kB · 1 download

what about 1989?

 

[uncle W]

1 minute ago, LibertyBell said:

what about 1989?

 

1989 was cold...I don't see that kind of cold or storm...1971 was cold before the storm but moderated and most of the precip was rain in the city...Poconos got snow...

[Brian5671]

18 minutes ago, MJO812 said:

It's a weather forum right? It's not about posting the maps. It's about pattern recognition and the pattern is about to get better as we head into late month. 

I'd leave the day 10 OP maps in banter.  Post ensembles etc if you're going to post a map.  Otherwise discussion is fine.  

[MJO812]

20 minutes ago, Brian5671 said:

I'd leave the day 10 OP maps in banter.  Post ensembles etc if you're going to post a map.  Otherwise discussion is fine.  

Very true 

Im a weenie

[MJO812]

[qg_omega]

that would be fun, unlike the last storm having a 963 low off LI with strong CAA = mega wind.

[MJO812]

38 minutes ago, qg_omega said:

that would be fun, unlike the last storm having a 963 low off LI with strong CAA = mega wind.

Gfs is a cold front as of right now 

[TriPol]

A sub 965 low sitting right off of our coast in January would get some people very excited around here. Being November, less so, but still interesting to follow nonetheless.

[wdrag]

1 hour ago, MJO812 said:

It's a weather forum right? It's not about posting the maps. It's about pattern recognition and the pattern is about to get better as we head into late month. 

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.   

 

[wdrag]

2 minutes ago, TriPol said:

A sub 965 low sitting right off of our coast in January would get some people very excited around here. Being November, less so, but still interesting to follow nonetheless.

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. 

[wdrag]

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

[MJO812]

The models at 12z are more northern stream dependent.

[wdrag]

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. 

[wdrag]

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.