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wdrag

Meteorologist
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Everything posted by wdrag

  1. Watch CMC trends... it tends to run warmer than NAM. HRRR ag 48 hours tends to run warm and then as we trend close toT0 it should cool. Those two models are my overall operational experiences. Stats are helpful...they temper enthusiasm but sample size can also have new contributions that are not in the more plentiful solutions. NBM has been steady through all the recent dailies. Even 18z EC has only 33F NYC Sat night... good VV and timing with the midnight ob might yield an inch Manhattan. Think its going to be interesting NYC and northern LI. Nothing off the table yet...in my mind. I want to see if the 00z/5 12KM can settle on something more reasonable than its 18z predecessor. I'll be sleeping when it comes in.
  2. western USA looks like it wants to seep east. Seems like we have an interesting two months in progress.
  3. No more nail biting there, I don't think. Northern LI-NYC have a hard time with my expectation T-2" due to above freezing temps. You still have hope at the onset 5-9P Sat and Sunday departure 9A-3P. Just have to be realistic. Here's the Blend of models from 2AM today.
  4. 18z EPS is within a tenth of an inch on its new qpf for the Sat night -Sunday morning snow storm. I've added an 18z EPS graphic 10 to 1 ratio chance of 4+. While I do not like using 10 to 1 ratio as a first guess... in the all snow region 10 to 1-Kuchera should work but always keeping in mind the base Positive snow depth change. I'll keep pounding this since it's the easiest way to reduce disappointment. For NYC... EPS Positive snow depth change is 2" now...so within there 1-4 bracket. We're still about 72 hour from the start... so I can't say its a lock yet but hope exists for northern and Western LI to break the less than 2" curse.
  5. That's because many are using 10 to 1. That doesn't work well with melting processes. Everyone in the longer range should start with a base of POSITIVE snow depth change. Then you can look at top end of the range with the 10 to 1, if no sleet/rain. Sleet is converted the same way as snow in the 10 to 1 so it biases amounts high along the warmer edge of the snowfall forecast. There will be banding and we can look at that more closely Friday, with greater confidence. I think we'll see clusters of power outages from wet snow and gusty northeast winds 30-40 MPH early Sunday somewhere near I78 if the snowfall there is 4" or more and falling at temps of 32-33F. Otherwise, I kind of think the original plan thread plan still looks reasonable. Impacts will be much more substantial 9th-11th with I think widespread river-small stream flooding up and down the east coast along the I95 corridor from NNJ southward to Philly and down to NC. Some rivers may go into the low end of the major flood category, provided two storm rainfalls exceed 3". This and wind damage potential looks pretty significant across the eastern third of the country for 9th-10th, plus of course 1/2-3" wet snow I95 west to start that second storm. Temps into the 50s on Wednesday the 10th I84 southward will add the snowmelt contribution up here in NJ southeast PA.
  6. You're welcome to chatter here about he 10th, but for sure after the 7th all that belongs in the current two storm thread. I have no plans to start a snow thread for the 13th-15th, until the 10th when we are solely posting damage combo 3" water equivalent snowmelt-rainfall/wind reports in the obs thread for the 9th-10th, that one I'll start the morning of the 9th. For now I'm now seldom commenting on modeling for both these next two storms in the primary 6-7 9-10 thread.
  7. Hi! Haven read anything since last eve... I'm sure there was consternation with the 00z/06z GEFS-GFS. Fortunately the EPS is back up as is the CMCE. No change to my own overall thinking since the thread inception, NYC 1-4" to be further adjusted if needed. Just caught Don's post about rations. Good post. Won't be back to post til sometime this eve. Was on call First Aid driver overnight with two calls. Enjoy as you can what's coming 6-7 (split short waves makes this a 24 hour event instead of one bombing 12 hour storm), 9-10 and now looks more and more 13-14. I know if you dont get 4" of snow, unhappiness. s LI looks worst chance 1". At least this was a tracker. It's coming but exact details of snowfall etc tbd.
  8. For the record nationally: inclusive of our own top 10 wettest Dec, some climate sites top 5. Top 3 warmest. snapshot via CP, EWR, ABE for both temp/qpf vs yearly reality.
  9. fwiw: BOM has a solid 6-14" inland from I95 for our subforum and by 00z/11 about 4" total qpf. These are significant events coming.. how they play? Don's good severity post will need followup... preferably 530P when all the NWS office collaborative data has been meshed. Cant post again til tonight--- hoping these next two cycles stay the course and don't abruptly corrupt.
  10. Don: could post on severity index. Go for it on updating. I won't recheck til tonight but the probs are up to 40% moderate impact just inland from I95. There will be fluctuations on axis but the I think WPC has defined this reasonably well. I like 5-10 spotty higher in their blues, but we have yet to account for mid level warming...so patience. LI just seems a little warm to me but I could be wrong. For now I think heaviest snow west of I95 and lets hope something sticks in CP. For sure an event is coming, imo (95% chance).
  11. well done imo. We'll see what happens. Tomorrow (2nd) will be D5 for the EC. I still am leery of much snow NYC/LI--- I could easily be wrong. I'm just not confident of PTYPE with general 1000-500 thickness over 540. I may not be able to post again til Tuesday night.
  12. yes, I agree... the only thing I can't count on yet is 8-12 Lehigh Valley... yes on the equiv qpf but am unsure on all snow there. I just checked... 19z BOM is hanging tough on 4-7"axis e PA though NNJ n of I80 to CT and qpf by 00z/1 1of 3-4". We'll see if the magnitudes hold. I wasn't too keen on that AFD. You need to offer guidance for preparations. NHC is ahead of our forecast offices by and large on doing that (my opinion only but not necessarily shared by many) and if we go back to the CPC outlook from last Friday that was posted here... they too offered some info for people who need to think about options (8--12 days in advance, including my own personal work life snow/wind/flooding rains- I work for the county inspecting Guiderails, drain pipes, bridges etc)). A forecaster arbitrarily capping a pop is overriding national center guidance which is 88% for NYC. That sitting on the fence forecast for D6 is eventually going to get AI'd out... models are getting better. I'd say capping a pop is more reasonable when you're on the gradient of much to nil. One of those POPS Sagt night or Sunday has to be higher than 50%. For now, we in the NYC subforum continue in the max storminess axis. Yes this could change... but the longer we stay in this axis, the less chance for a miss. Now its a matter of communicating concerns. There's always a chance of failure but my own choice is try to ballpark potential well in advance, especially if BOM/multi ensemble support. 18z/1 EPS is almost identical to the 12z... if anything slightly flatter with a decent short wave and strong 5H LF quad with jet out across there Carolinas and signs of RRQ support south of Nova Scotia with an 850 low edging ever further north but forming from NJ- eastward. The GEFS is now much sharper and unless the models flatten out in future cycles, I find it hard to believe we will avoid a significant precip event. It's FAST... most of it out of here by 12 or 15z Sunday which means most of this event is 12-18 hours (I think). Failure can occur. I sort of think, if its going to fail, the models will have to make an abrupt shift January 2nd cycles (just like the pre Christmas storm last year when the EC suddenly went inside runner around D6 and stayed there and wiped out a snow event).
  13. Just need to hold all of us accountable. I can't add anything more than what is within the thread. Models are good, but not that good on ptype. When we use 10-1, that's outdated methodology that doesn't really properly baseline accumulation. I always start with positive snow depth change. If you have sleet.... that inflates snow totals considerably. 10 to 1 or Kuchera might be good to communicate when we get within 3 days or so, and you know no mix and temps aob 32 at the surface throughout. Positive snow depth change doesn't do so well, imo, in these 33-34F nighttime heavy wet snows when the snow overcomes melting processes.
  14. Agree 100%. While reality has not occurred... if this general modeling continues through both storms... this will be a memorable pair of events, NOT THE WORST but for January will rank as significant I think this more of a spring setup. We cant forget wind and coastal flooding. If the first one misses to our south, then the above paragraph is misleading.
  15. I am in agreement with you. If we are to suppress big time, I think we'll know at this time tomorrow. Models are improving D5 in and few major debacles that I recall. Anyone can refresh me on debacles since 2022 inside 5 days. Stuff I look at: 13z BOM rainfall through the 10th... VERY large but the 4" probably will shrink to 3. IF NOT, widespread moderate flooding would be my concern 10th-11th after the basic qpfs are done. BOM snowfall through Sunday eve. This is NWS base. BOM includes percentages of models and ensembles. I added one frequent flooder in NJ, but to give an idea what NWS uses for longer range til reality qpf hits the basin. This is for NAEFS 2.5" 4th-10th.
  16. A couple things: Added WPC 17z met expert desk on winter wx. They aren't perfect but they have tools we dont and faster. Also, I see a lot of references to big busts in the past. I think modeling has generally improved since 2020. Maybe this is another but odds are against a 1/2"+ qpf miss I84 south. Ptype another story. The 16z WPC QPF was probably made before GEFS 12z qpf... but now when you take the remaining ensembles from CMCE and probably the EPS...they have this more or less right in their 12z products. Also the thread was written for two storms... inclusive of large qpf by 00z/11 2-iso 6", potential for damaging wind and a snow event possibility to track. I dont think we said NYC would get heavy snow but we have members in CT/NJe PA that are interested. If I were to write thread for only NYC... much less often.
  17. fwiw...new 12z WPC qpf... similar to previous for Sunday. I do see all the discussion on suppression so will wait this out. Ensembles I think are best for now with the caution that the suppressed solution could win out. New D6 winter wx not available for a while.
  18. For the 2m temps this far in advance suggest staying ensembles, which are all available in Trop Tidbits. All suggest above freezing to I80 in NJ and up to coastal CT. That mans the fringe temp transition near 33F is wet snow, provided cold enough above the BL. Just too far in advance except as pre prev ensemble posts and NBE. I would not count on much accum NYC... I can live with 1-3 for now.
  19. I like the sloppy 1-3"LI/NYC... that definitely appears more likely to me since the 06Z/EPS while slightly less amplified, is faster and certainly permits qpf up here... Here's the EPS 850MB at 144 hours and the EPS snow depth change. Provided the EPS does not flatten out much from the 06z/1 cycle as we go into the event, then we'll do well. The 06z GEFS looks sharper...all modeling faster. My guess this is a Sat night-Sunday event. Click images for clarity. The 850 low is over Ches Bay at this 144 hr image.
  20. Always concerned about how good it looks for snow this far out. The GEFS in the past 24 hours is showing a slightly sharpening of the causative short wave -- that still is troublingly far south. The EPS however (as opposed to the 00z/1 op we saw) is showing a negative tilt short wave and strengthening trend since 12 hours ago. It validates the ensemble chance of 3+ by the NWS shown in.darker green, and 4+ by the EPS, and note the blend of models (07z/1 version) for both storms. Things will change... I dont know how but there is little doubt in my mind that a 6+ axis will occur probably from the Virginias somewhere across PA. After that... I dont know. So the GEFS overall is the weakest in its ensembles. I think the 12z/2 modeling will be important, since by then global models will be pretty accurate on the upper air pattern with probably no major change in the 500MB after that. I95 eastward to the coast is my greatest area of uncertainty (ptype) as well as just north of I84 (northern fringe-suppression). Of interest is the likelihood that whatever wet snow occurs PA/NJ this c coming weekend, it gets washed away by next Wednesday the 10th. The rapid snowmelt and storm two qpf have me concerned about renewed flooding, all dependent on qpf at this stage. You dont want to see the BOM total qpf by 00z/11. It seems overall high but if occurred even 1" less, would mean river flooding compared to the more vigorous first event of a couple weeks. I just can't post it... it surprised me. Lets get storm one up here first. Also...coastal wind damage-power outage unknown risk for storm one DE/NJ/LI? and then storm two fairly extensive northeast USA around the 9th-10th? Power outages as well documented here is not an easy predictor but knowing of potential can be helpful. If interested, please click the image below for clarity.
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