wdrag

Good Wednesday morning all, No significant change to this outlook. ICON is out to sea (east and a miss), 00z/25 GEFS and EPS are similar to yesterday..EPS now a little heavier on QPF as is WPC heavier on QPF... but still a range of possibilities including tracking Appalachians or maybe closer to e PA? NAEFS is going for phasing and while it's surface response lags, it's also getting stronger. Probably not good to hang our hats on the strongest EC solution but some of the op runs are interestingly strong(not sure it will be quite as strong as Nov 15, but weakened ground due to Thursday=Thanksgiving mornings rain may compensate for less leafed trees) I've included below this mornings D4-8 discussion from SPC...note this southern system may carry severe from the Gulf states to there mid-Atlantic. Probs so far too low, in part do to model differences. (i underlined). Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0354 AM CST Wed Nov 25 2020 Valid 281200Z - 031200Z ...DISCUSSION... Medium-range guidance has come into better agreement regarding the eastward advance of an upper low over the southern Plains on Day 4/Saturday. Any severe potential Saturday appears to be confined along/south of a surface boundary which should be located across parts of coastal/south TX and perhaps southern LA. Some phasing of this upper low with a northern-stream upper trough over the Midwest seems probable on Day 5/Sunday. A northward advance of a partially modified Gulf airmass may occur over parts of the Southeast Sunday, with an associated isolated/marginal severe risk. Differences in the evolution of a highly amplified upper trough/low over the eastern states become apparent in medium-range guidance by Day 6/Monday. Regardless, a continued isolated/marginal severe threat may exist Monday across the warm sector of a deepening surface cyclone from parts of FL and the Southeast along the East Coast and potentially extending into the Mid-Atlantic. For Day 4/Saturday through Day 6/Monday, too much uncertainty currently exists regarding inland destabilization to include 15% severe probabilities for any day. 634A/25

Probably my last on this for the night. Ice pellets occurring in this band at State College in the geographic center of PA. mPing.

If this were summer? We'd wonder why modeling is so conservative on a band of snow and ice pellet showers racing (45 MPH?) eastward across N Central PA. As it stands...the 18z EC is trying... and may allow a sprinkle here and there in NYC metro between 2A-430A? We'll be sleeping and not notice if it does make it. If it was summer, it might be a band of thunderstorms. Hopefully the HRRR, which is supposed to be good at picking up convection, would have this. Right now, I think it's lagging. I see mPing just picked up on ice pellets at State College. Miniscule minor Fgen/WAA mainly 800-600MB.

Not much going on wintry weather wise so I figured I'd perk up the nw-ne suburbs. Models seem to be missing the fgen band racing across nrn PA. May last longer than any of the modeling and come in as a 15 minute snow or ice pellet shower across ne PA and se NYS n and w of POU between 1130PM and 230AM. Trace.

Caution: VERYYYYYYY early and this could end up much less robust than outlined below, if the northern and southern streams don't phase, or phase early enough into a closed LOW somewhere over NYS/PA/OHIO. (something always changes from what we see 7 days away but it's posted since there may be some discussion about the potential). Modeling has been trending to a large sub-1000MB sfc low early next week, with it's maximum strength in the mid Atlantic states. Ensembles to start, offer a solid 1" of rain and wind gusts 40 MPH. 12z/24 EPS/GEFS 850MB wind at 06z/1 is around 45KT, not the operational magnitude of the southerly GFS 65KT, GGEM 70KT, ECMWF 75KT, found over LI. Added the baseline D7 graphics from WPC and view these as a start. Added 12z/24 GFS lower wind field for LGA. The Richardson # preliminarily in this single 12z/24 member cycle allows downward from roughly 925MB. (50 KT). Also added the EC PWAT (tropical connection briefly 1.6"+). The 12z/24 operational EC has KI mid 30s generating lightning s of LI suggesting a High Shear Low Cape wind event. Strongest wind threat this early in the modeling is LI/CT. (did not say 50 KT gusts will occur but based only on the modeling, it's possible). A very small chance of some backside snow cover higher terrain western-northern suburbs.... To avoid disappointment on a big wet wind storm not happening, prepare for the more routine WPC scenario, BUT monitor.

Good afternoon, If you can, give me til ~ 530P when I can more thoroughly assess for a topic Nov 30-Dec 1 storm and associated hazards. Doing Christmas things right now. 12z run jumped upon something...suddenly multiple models pretty intense storm. Not a lock for this strong and would like to review a bunch of ensemble stuff after 4P. As noted by others Op runs from GFS, CMC, ICON among the few checked.

No topic yet on what I think is a probable Nov 30-Dec 1 big storm with greatest magnitude here (wind/rain and low prob backside covering of snow I84 high terrain). This per ensemble departures from normal. 00z/24 EC came back to 45-55 MPH gusts in the op run. Continued Nino look first half Dec BUT I think the 500 ridge may be a touch too far east in early Dec, however some interesting coastal opportunities seem to be presented in the ensembled guidance. Also I respect the considerations presented on Pacific firehose impressions and maybe a cruddy looking pattern. To me it's not as bad as now. Not sure how AO is considered so positive. I don't see it developing that way at all. There is a general suppressed blocking trend in the modeling (see GEFS confidence graphic attached at 216 hours - RMOP--- very confident). MJO evolution to me (novice) has mixed messaging though overall no outrageous warm signal for us (am I missing something????just let me-us know) - and generally trending possibly to a weak phase 1 or 8?? Euro weeklies: Best to look at 500MB, then 850 MB temp pattern for unfolding surface response. Warm in Canada doesn't mean above freezing (nighttimes lengthening there with adequate snow cover). After discussion last year with a met friend on the New England forum, I don't look at the sfc temp weeklies at all beyond week two. They just don't seem to verify very well. I may not be able to respond to any thoughts-corrections until midday-this afternoon. Have a good day. 736A/24

A passing flurry possible this morning Poconos into se NYS interior high terrain mainly n of I84 A short period of flurries appears possible tonight between midnight - 3AM in the Poconos and se NYS high terrain mainly n of I84-NAM has pretty good FGEN rolling through (better than Sunday morning). Wind post for 30th-Dec 1 on main NYC forum and no topic planned before late today or Wednesday on what should be a big storm, with maybe a little post storm dusting on Dec 1???

I don't know. The following are a bunch of words. I'm a little confused about NAEFS evolution. Typically it's the GFS that is too slow coming out of the SW USA but in this case, it's faster and I like it (it doesn't lock up in desert sw). Whether I like it and am more right than wrong??? What I do see is quite a bit of potential the first two weeks of Dec for southern stream short waves coming up off the east coast. In other words... precip threats but whether snow or rain??? The NAEFS is trending confidently below normal across Dixie early December, and above normal southern Canada. That is a broad displacement and an active southern stream (I think). Could be wrong ,especially if the future cycles of the NAEFS lose the modeled departures. I may comment tomorrow or Wednesday? Todays cycle has quite a bit of 200MB jet constantly south of 37N, especially early Dec and it is modeled the predominant jet in N America. Doesn't seem Nina like? More Nino-like to me, at least temporarily. No????? It's modeling-subject to large errors beyond 7 days as you noted earlier? Yourself and others probably understand whether what is ensemble modeled, can realistically happen Dec 1-14. For me, it's probably best to not broadcast too much hope but be aware of what appears to be a somewhat better pattern of "opportunities" to begin DJF. Maybe we can an inch or two of snow out of this pattern in NYC in early Dec?

I see it in 12z/23 CMC. No question phasing for a big storm is complicated (not a high prob) and if comes in pieces, how it all transpires makes a sig difference in ptype outcomes this time of year. Monitoring. If this potential continues another two days, may start a 48-72 hr topic on wet wind event, followed by ptype-accumulative western-northwestern suburbs snow. Sooooo. early right now and prefer not give this second storm idea much credence, yet. Another post somewhere in NYC forum a day or 3 ago had also mentioned the colder more interesting look to DEC around here. In the end, we've got to keep in mind stats-climo.

Good morning, No topic yet but 5 successive cycles of the EC indicates the potential for a period of 45-55MPH gusts Nov 30 or early Dec 1 entire NYC forum. Something is coming in that two day period... sizable trough and small chance of a northern-southern stream phaser.

Good Monday morning all (Nov 23), Yesterday morning had the slightest of an ice pellet-snow shower north of I-84 per reports here and mPing. We're going to try to out-perform that Wednesday morning and a little caution is urged on a big warmup for Thanksgiving morning n of I-84. So, no big snowstorms foreseen in November I-84 northward, but eventually the more seasonable first half of December might produce something that is more than 3" for I-84. Tuesday: Maybe a flurry? (Accumulative snow showers concentrated near Oneida Lake in NYS). Wednesday: A short period of snow or flurries is anticipated between 1AM and 10AM, that could produce a covering (less than 1"), especially Poconos, CT/MA and the Adirondacks. See UKMET snow cover graphic which includes snow showers in upper NYS today and tomorrow. The idea is the southern edge of the snow...while it may not be that far south, at least a flurry is anticipated that far south, per increasingly south modeling of the past 24 hours. Which also tells me, that it may be quite cool on Thanksgiving n of I84...high terrain of slight icing interest there. For now, that is an outlier possibility for our NYC forum northern fringe. Wind: will mention for entire forum Nov 30 or Dec 1. Looking forward to see how this all turns out.

Hi... After review of what happened today... not much, but a very brief period of ice pellets did occur in at least some spots of our NYC nw-ne suburbs forum; just north of I84 this morning trending to a brief mix of snow further north of POU. Models tend to underplay the very minor lead thrusts of warmer air arriving and so, am glad a few on here may have seen 5 minutes of wintry weather. We'll give it another try Wednesday morning near daybreak. Very brief and overall inconsequential but some of the modeling is coming back south. We'll see what happens. Meanwhile a few flurries in the wake of the cold front tomorrow=Monday, may cross some of our higher terrain late Monday or Tuesday.

and as recently as around 11A-1115A... reports of snow/sleet just s of Kingston NY and two reports of ice pellets near Waterbury CT.

So far only sprinkles MPO, MSV, Wantage NJ, with ice pellets near Carbondale PA around 930A and apparently now vicinity MSV. Probably sprinkles further e in CT lower elevations. at 1015A.

Pretty dead on the NYC forum the past day or so... yep, not much to talk about. There is a 2 hour northeastward transitory window of opportunity for the higher terrain of the I84 corridor to see a showery spritz of mPING noticeable ice pellets-flurries, or freezing rain sprinkles, between 8A-2P. That band as this is written 647AM is now trying to grow east -northeastward between I78-I80 in PA-NJ. So far, dry air at 850MB is evaporating whatever is trying to reach the ground. This band of showery very light precipitation should gradually organize a bit more as it passes out of ne PA/se NYS after 1030AM and heads toward ALB-CEF. That's as exciting as i see it on front end wintry events. The Wed morning possibility still exists, but chances are 80% that it won't occur. sighhhh

Following up this Saturday morning nw suburbs! It's Nov 21 and while no big snowstorms are outlooked here through November, it's not necessarily completely devoid of snow. A brief period of ice pellets-flurries or freezing rain is possible for the I-84 high terrain corridor 9A-3P Sunday, especially Poconos and possibly extreme nw NJ/interior se NYS There may be another period of snow I-84 northward Wednesday morning, with less than 1" high terrain accumulation possible (see 00z/21 UKMET). These are exceedingly minor events, if they were to occur but it's something that may briefly spark mPING interest for the wintry weather diehards (me), IF they were to occur. NO guarantee's. This paragraph is based on 00z/21 multi model usage, leaning on the NAM-3K, UKMET, SPC HREF. Have added 06/21 NAM FGEN modeled prediction for ~9A Sunday. Right now that says little or nothing for I84 but if that happens to extend a little further east (red is FGEN) in future modeling-reality, then we're in. Thermal profile for MSV (Monticello NY) suggests ice pellets or freezing rain, BUT, if the fgen lift is stronger then the column cools the warmer dryer layer near 850 MB seen around 15z (10A) and suddenly we have a few minutes of snow. For now, it's a long shot and all I can excited about in the next few days. When you look at the KMSV profile, any precip before 7PM Sunday night certainly can freeze over the higher terrain (sub 32F profile). The question then becomes, is the modeling a touch too cold there in the NYS high terrain? (I also use KMSV for extreme nw NJ near State Route 23 (High Point-Montague and Wantage). 655A/21

Good morning, I did not post a minuscule snow outlook on the main forum since it won't affect NYC but tossed it in the nw suburbs portion where even extreme nw NJ may briefly (hour or two) see some snow or sleet Sunday and Wednesday. Wish it were better but I think of this... as scientifically depressing the outlooks herein for this winter, the sample size can always be expanded with normal seasonal snowfall. Timing-timing-timing of short waves with cold air.

Good Friday morning nw suburbs! It's Nov 20 and while no big snowstorms are outlooked here through November, it's not completely devoid of snow. A brief period of little or no accumulation for the I-84 corridor is "possible" 9A-3P Sunday. There may be another period of snow I-84 northward Wednesday morning, with less than 2" high terrain accumulation possible. These are exceedingly minor events, if they were to occur but it's something that may briefly dress up the landscape, IF they were to occur. NO guarantee's. This paragraph is based on 00z/20 multi model usage, leaning on the NAM-3K, UKMET, SPC SREF plumes and nearby ECMWF hints.

fwiw... past 24 hours rough idea of new snowfall. This part of Wantage NJ Trace both yesterday and this morning.

Trace of snow showers here in Wantage NJ since 730A. mPing has some snow obs.

One note: and this is written not knowing if a TOR survey is being conducted... but warnings are warnings--- whether they verify is another matter. Therefore, what to me is most important on TOR climo, is not the # of warnings but # of occurrences. The warning for me only means big wind is being detected with probable rotation to the surface. I didn't check but I suspect this was an updated warning (TOR) embedded in what previously had been a big lead time SVR. To me the prior SVR would be the critical notifier-headsup... take cover! EF1 (86MPH+ ) or greater is more important to me than the EF0's- from a science standpoint I understand EF0 documentation but from a lead time value added here in the northeast with many fleeting short lived EF0 signatures, the prior SVR was critical. For what it's worth, HSLC environments like yesterday's can produce embedded TOR's and was what I was hinting at in pre-event discussion of breaks in a line etc. I just didn't want to name it... modeling for the TOR I thought was minimal and mentioning TOR puts pressure on forecasters, just via ph calls. I think it gets too much attention unless it's clearly signaled via modeling, radar, debris signatures and most of all ..ground truth.. Again, this is written without knowledge if there was a tornado or not.

Hi. I don't know on both, perhaps others might. Strong PPP falls and some rises behind may have caused the seiche on LErie along with strong westerly gradient. Presume you meant 1.5 ft seiche...not 15 ft tsunami-like impact. Derecho... long lived for sure, and not sure if enough 75 MPH wind gusts? Am sure others may have more info to answer. Here's some info you can do some additional research into. When i think of Derecho...I tend to think spring-summer and many 75-90 MPH gusts enroute. However, I must be corrected if am wrong. Thanks. One of the authors, is the recently passed, excellent SELS-SPC forecaster-teacher = Bob Johns.

Just for the fun of it...take a look back at the Eta Remnant potential thread p2 1148AM Friday post which had the timing of the squall line. RGEM vs NAM3K. Amazing RGEM timing. This was just 8 hours before this damage thread was started Friday evening. I've been liking the RGEM lately...expresses qpf areas nicely, and timing. Might be slightly too robust on qpf amount but overall... a worthy check through the Tropical Tidbits link, or your other favorite resources.

Some early 5 day summary info appended. Includes NYS mesonet and radar-sensor qpf for the entire period. (i in Wantage NJ had only .92 on the edge of the blue area in nw NJ). Added CoCoRAHS around 115PM. Initial topic 1-3" was better than the followup 2-4 iso 6 for our NYC forum. Rainy-drizzly a good part of the daylight hours Wed-Thu-Fri, then final event arrived very late in the day Sunday the 15th.