wdrag

MPIng'd snow for Wantage NJ. It's just flurries but flake size decent. 32.7/25.3

Here's what you saw... May have more info in a few hours. It was their 442PM report. Thanks...

Helpful... Let's call it zero for now, OKX has to validate one way or the other. I'm not even 100% sure NYC will see snow today- i still think so. It's crossing the Delaware now and I expect to mPING here in Wantage by 1015A.

Good Wednesday morning everyone, No change for me in this 5 day period. I think we could see a change develop in the way the GFS is modeling the 14th (a b luging weak wave of qpf. Ditto the 16th-17th which looks to me cold enough for snow or ice, even down to NNJ/NYC- BUT, I'm not jumping the gun on this since the NAEFS isn't showing much qpf-development. If....and when its does, the snow-rain thickness fields will adjust a bit tighter-warmer. Still... to me it's a 5 day period of interest. Take whatever we can get. Am not looking beyond the 18th, until we know wintery weather does not occur as topic'd.

Hi! I just checked CP Climate data and I dont see any snow...did I misread the CLI for CP? Also, is NKNYC CP...kind of looks like it but I might be mistaken. Thanks for your further clarifications and previous alerts. I'll look for your replies. And so for today: Still uncertainty... my guess is CP will have a hard time measuring 0.1" unless it comes down hard, because of above freezing temps. I added the 06z/9 NAM profile for LGA... see the temps above freezing BUT a dip to nearr freezing around 2PM, co-located the the highest rh descending to the surface (Blue-purple-see legend) and also co-located with looks like to be a minor shot of lift through the vaunted DGZ (dendritic growth zone). We'll see how this plays out. I still could see a few sprinkles mixed at onset in NYC but a swift change to all snow, presuming the precipitation arrives. Last graphic is the hrrrX variable density snowfall map...conservative so this is sent to try to keep things in perspective. 603A/9

This posts due to forum interest in wintry weather, but with uncertainty on evolution of precipitation events and how far south ice or snow can develop (even a low chance NYC). Marginal thermal profiles may limit snow or ice to I84 northward but may be worth monitoring for a minor or moderate wintry weather event I84. The NAEFS pattern along with various models, though cyclically inconsistent, suggest the possibility that the latter part of the Mondays(14th) precipitation could be a little ice or even end as snow along the I84 corridor. A wintry event possibility. Evolution thereafter is uncertain but it appears there will be some sort of decent storm system heading into the northeast USA which has a chance to involve snow-ice, at least along the I84 corridor. It's possible short wave interactions will force a northward buckle of the thicknesses and result in all rain but for now, I think there is enough model guidance to open the door for some wintry weather, mainly I84, sometime between 16th-18th. Confidence for one or two precipitation events in that 5 day period is above average, and a good sign is the constancy of a decently strong upper level jet just to our south (LF quad= exit region), frequently with the jet core near VA. Normal High Low at CP next week is ~43-32. Added two graphics: the WPC midday Tuesday (8th) chance of of more than 1/4" frozen water equivalent Monday the 14th. and the CPC D6-10 outlook for the 14th-18th. As we draw closer, it may be that we'll delete some of this and refocus the topic title- for now, this should hold us. Let's see if we can get a little winter in our area next week.

First snow of the year at CP? Snow showers are likely to dust the NY forum suburbs between 9A and 5P Wednesday 12/9/20. Does CP ASOS see snow and then is it the first Trace or tenth of the 2020-21 season? The sooner the snow showers arrive (presuming they arrive), the better the chance of measuring on the snow board. Most roads just wet but the northern and western hilly suburbs could have up to 1/2 or 3/4" on the snow board-grass-roofs-even a bit on some untreated pavement?", with I84 high terrain possibly an inch in PA NYS, lesser amounts you proceed east across the Hudson into I84 CT. No guarantees of precipitation in NYC (small chance its a mix of rain/snow in NYC) but a pretty good short wave passage along with NAM/RGEM/RDPS support all have it to the city (not necessarily measurable but snow in the air). Central Park climate data base (entire back to 1869), the mean first date of measurable there is December 7. mPING reports will assist what we see on radar Wednesday morning.

Will post two topics by 815 PM. Both shakey but there is so much interest in winter that I think there is enough model evidence to get something out there.

I just checked for myself. I don't want to waste forum time on a 1 inch gust 45 MPH routine event. However... I or yourselves can post a thread topic. I just need to build some confidence. It's been on my radar but I'm not willing to commit a thread this far out.... looking at marginality for the NYC forum-mainly I84 corridor, but certainly potential, any, date 16,18. My first interest lies in a possible (12z/8 GEFS 50% chance) first T snow (if ASOS sees it as snow), lower prob measurable (0.1") CP sometime between 10A-2P Wednesday 12/9. Normal first date of measurable in the entire CP (thread X) database is around 12/7. With hope... but not necessarily science yet.

Wantage NJ had a few flakes prior to 650A. Outlook: No snowstorms prior to the 16th. Wednesday 4AM to 2PM: A band of decent snow or snow showers lasting an hour or two will pass southeastward through the area with 1/2-2" Poconos but generally a Trace to 3/4" elsewhere. Might be a brief untreated hazard prior to 10AM. Wed-Sat 16th-19th: Might provide a small amount of marginally hazardous snowfall north of I84?? From two separate storms.

Yes but lapse rates were MUCH MUCH steeper and as i recall there was a decent surface trough.

Warmer than normal DEC here... i understand... Still, something not fitting all the negatives on snow. I could be wrong but this not last winter. Seems to me modeling is hanging on to weak blocking in the N Atlantic for many days, and I see a ridge in AK for awhile (7 more days) and an undercutting Pac Jet. This may provide for more opportunities beyond the 16th? I see the MJO indicies are trending weaker with time which may be a climo bias? I know the modeled MJO phase is not favorable for us, but I am interested in this pattern... I just dont see cold air ripping off to the east in southern Canada as easily in the GEFS dailies through D16 (laying in wait for something in the southern stream?). Again a GEFS blocking bias? And yes, it's nice to have cold air in place PRIOR to a precip event. Critical science is needed here to void my snow interest beyond the 16th. Have at it. fwiw...i checked CP first measurable snow date in xmacis... looks like Dec 7 (today) over the entire CP climate history. Monitoring Wednesday's 12z/7 3K NAM forenoon snow shower risk (probably melt on contact?, but of minor interest). Lapse rates don't look all that interesting... sort of surprised by the modeling of snow showers down to NYC at ~54 hrs.

Hi. My wrap addition. Added snow reports that were accepted by the NWS and the lightning archive. While one can argue on the use of models and models vs pattern recognition, one difficulty continues over the years... use of 10 to 1 snow ratios. We need to be careful about this. NWS has a blended snow ratio tool (every 6 hours or less which can be interpolated). Overall model intent was good (except the one day of a very westward set of solutions) but model snowfall was way overdone on amounts Southern NH southward that performed the phase change reasonably well (NAM/EC). The over-forecast was probably due to the occurrence of wet snow during 33-34F air temp, non frozen ground and much of it during daylight hours. My guess (there may be some verification out there?) was a 6 to 1 snow water ratio (if someone can provide some documentation on ratio-that would be helpful)? This especially since many folks were speaking or imaging large flakes (DGZ ideal or less than ideal). Snow accumulation may have as much or nearly as much to do with ratios as DGZ. I always start with total positive snowfall change, then check the usually heavier Ferrier, and then IF frozen ground and lower thicknesses below 5380 DM - I will look to as much as 10 to 1 or Kuchera. These are painfully earned considerations over my life. I may be wrong on Kuchera... but my guess is Kuchera does not take into account 33F melting that was modeled in the EC 2m temps? Maybe it does... Sometimes Kuchera works excellent, but my experience is that it is best when clearly the sounding does not allow any melting or wet snowflakes (colder scenarios). Hopefully this makes sense. I'm open to better science- if you have it, please add it (I do not have BUFKIT). My second thoughts and CT did add something recently on this... This elevation snowstorm (event?) while not the biggest ever (never was supposed to be), not only placed ORH a foot temporarily ahead of normal, the daily record setting 9.6" was also about 14-15% of the climate 1981-2010 normal. Since the general thinking here our forum and elsewhere, is a La Nina winter and below normal snowfall... it may be that ORH received 20% of it's seasonal total (normal is 64.1")????? I don't know. Whether we may have paid too much attention to yesterdays storm, it was probably an important one for this winter at ORH. I fervently hope that I'm wrong and we don't look back at this early Dec snowstorm, as the biggie (like last cold seasons Dec 1-2 event). arghhhh

Hello... my own version of the wrap. QPF from 2 days of Co CoRAHS, CoCoRAHS snowfall, and LSR'd snowfall. The NOHRSC is above. Closest lightning was quite far away per the added lightning archive. This to compare with modeled qpf/snowfall and topic intent of coverage. While one can argue on the use of models and models vs pattern recognition, one difficulty continues over the years... use of 10 to 1 snow ratios. We need to be careful about this. NWS has a blended snow ratio tool (every 6 hours or less which can be interpolated). Overall model intent was good (except the one day of a very westward set of solutions) but snowfall was way overdone on amounts Southern NH southward on some of the models that did the phase change reasonably well. The over forecast was due to the occurrence of wet snow during 33-34F air temp, non frozen ground and much of it during daylight hours. My guess (there may be some verification out there?) was a 6 to 1 snow water ratio.

Snow reports as of a little while ago... probably incomplete mapping as of this check.

MUCH MUCH better. Just took a look at snow fall and many of these reports were not LSR'd (I don't think). Appreciate the update... lots to chase at these WFO's. Some easier to note what is timely, than at others. Do not like that statement: Latest. Always should have date-time. Permits a person to immediately know if something is timely for their use. Done w my complaint. Thanks for keeping me up to speed. Walt

Looking back: Original post Tue... too slow by 12 hours and no freezing rain. Rest OK. Had general 0.3-0.9" rainfall se NYS, ~1/2"extreme nw NJ otherwise widespread 1-2" there in NJ, also LI and CT. Will post complete CoCoRAHS summary qpf and snowfall tomorrow, around 1PM. This morning's expectations (my own): Wind gusts were 5 knots less than expected, no Thunder occurred. ECMWF Kuchera and all 10 to 1 ratios I think in general were too high especially valleys. I think snow ratios need to be taken into account when thinking of amounts. Accordingly power outages not as high as expected from combined snow and wind or wind alone. None of these elevation snows are easy: Other than the one day of extreme west modeling solutions, the overall modeling guided the main impact areas pretty good... For our NYC forum..a routine event, with knowledge that this is the fourth decent storm in the past 3 weeks (Nov 11-15, Nov 30, Dec 5). 759P/5

Presume that is 9.8? Thanks... I like the 7 to 1 snow ratio. NWS and/or others may analyze differently but for SNE it seems ballpark to me.

Noticed...must be a staffing problem or some other reason.

Looking back: Original post Tue... too slow by 12 hours and no freezing rain. Rest OK. Had general 0.3-0.9" rainfall se NYS, ~1/2"extreme nw NJ otherwise widespread 1-2" there in NJ, also LI and CT. Will post complete CoCoRAHS summary qpf and snowfall tomorrow, around 1PM. This morning's expectations (my own): Wind gusts were 5 knots less than expected, no Thunder occurred. ECMWF Kuchera and all 10 to 1 ratios I think in general were too high especially valleys. I think snow ratios need to be taken into account when thinking of amounts. Accordingly power outages not as high as expected from combined snow and wind or wind alone. None of these elevation snows are easy: Other than the one day of extreme west modeling solutions, the overall modeling guided the main impact areas pretty good... For our NYC forum..a routine event, with knowledge that this is the fourth decent storm in the past 3 weeks (Nov 11-15, Nov 30, Dec 5). 752P/5

Thanks John... helpful! Hope NWS has the reports other than your 3.5. Talk soon. Walt

Thanks... not seeing any reports of this. Unsure whether BOX has the reports, or they're short staffed? Thank you for this!

Checking back in: Recent 3 hours max gusts at working ASOS's etc. KACK: Nantucket, Nantucket Memorial Airport, MA, United States [46kt, 24m/s] KAUG: Augusta, Augusta State Airport, ME, United States [40kt, 21m/s] KGHG: Marshfield, MA, United States [40kt, 21m/s] KHYA: Hyannis, MA, United States [49kt, 25m/s] KLGD: La Grande, OR, United States [40kt, 21m/s] KMQE: East Milton, MA, United States [47kt, 24m/s] (I saw a MQE 50 kt also...) KMVY: Marthas Vineyard Airport, MA, United States [43kt, 22m/s] KMWN: Mount Washington, NH, United States [44kt, 23m/s] KPVC: Provincetown, MA, United States [49kt, 25m/s] KPYM: Plymouth, MA, United States [49kt, 25m/s] KRKD: Rockland / Knox, ME, United States [42kt, 22m/s] KTTD: Portland, Portland-Troutdale Airport, OR, United States [42kt, 22m/s] KUUU: Newport, Newport State Airport, RI, United States [42kt, 22m/s] Power outages: overall as of ~545P, and then broken down by state. Note: Wet snow the primary culprit but se MA has a fair amount from wind. Snow amounts so far look general 2-5" in the interior of SNE. 8" near BOW NH.

Power outages minor so far...

snowfall reports posted by the NWS so far. 2PM ish.