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NittanyWx

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Everything posted by NittanyWx

  1. NittanyWx
    Coastal marginal temps/mixing keep things at bay accumulation wise. it'll look nice for a period, you'll get some accumulation on grassy surfaces, but a lot of it will feel 'wasted'. It's still better than what it looked like a couple of days ago. This is game on north of the merritt/287.
  2. NittanyWx
    Similar thinking, pending 12z adjustments in track. I like this a lot in the 287-84-merritt-91 box
  3. NittanyWx
    taking under on that 12" by a significant margin
  4. NittanyWx
    I like this a lot for north of 287/Merritt, though a large chunk of our area is gonna waste some of the overnight precipitation to sleet and mix at the onset with the warm nose above 850 and best diurnal timing. This is a frustrating one for the coast, especially the island, but that's often the issue in marginal storms like this one.
  5. NittanyWx
    There is also tangential/research being done on what impact any SSW event has on the actual PV and the spatial distribution of 2m temperature anomalies/h5 pattern. There are statistically higher odds of certain loading and post event patterns depending on whether a displacement or full split event occurs.
  6. NittanyWx
    Tropics Check
  7. NittanyWx
    Once again, a clean eastward propagatation in subsidence...the models handled this well.
  8. NittanyWx
    OLR/VPA tracking:
  9. NittanyWx
    Background
  10. NittanyWx
    We're talking about very different time horizons. I'm not using a Euro monthly inside d7, I'm not using a Euro weekly inside D7. I am seeing W Pac subsidence inside d7 on most dynamic models though, and I'm also seeing upper level pattern shifts in regions of the tropics I forecast for reflect those changes. I don't think persistence is going to outperform the models inside d7, personally. But we can verify on Feb 5-6 and see whether that's true or not. I suspect the model will win in this Jan 29-Feb 5 window.
  11. NittanyWx
    Let's check back in a week and see whether the OLR/VP diagrams back up your claim. Because so far, this has 'rolled forward' as it were. Long term trends also are subject to sub-seasonal variability, so you're essentally boiling this down to a persistence forecast inside the d7 timeframe. I don't agree with that approach right now. Sub-seasonal variability still does occur even with bg warming and longer term signals you're describing persisting. If this was week 2 and this subsidence hadn't rolled forward, think it'd be fair to question whether this identified subsidence pattern ever emerges. But you're now arguing that a very strong +OLR anomaly west of the dateline is being misdiagnosed d 1-7 and therefore arguing more skill than the model inside the d7 window. I'm skeptical of that, but let's see.
  12. NittanyWx
    Just talking about the weather, man!
  13. NittanyWx
    Like there's a clear difference between saying 'the P8-1 response is not as clean as I'd hoped' in tropical forcing terms and arguing 'oh this is stuck in P7'. I have a hard time making the argument 'this is stuck in P7' when the eastward migration of VP200 anomalies has already occurred and there's a Subsidence/+ OLR signal just west of the dateline...and a pretty coherent one at that. That does NOT mean the MJO is 'not progressing'' What it does show, however, is the largely subjective nature of MJO usage...
  14. NittanyWx
    Your OLR maps here also show an eastward progression and reduction in W Pac forcing for the 6-10 day window. So, as diagnosed, a reduction in W Pac forcing and shift eastward. Do you want to try again? Here's another way to look at it Now if you wanted to make the argument that E pac forcing is not responding as cleanly as you'd hoped to -VP anomalies in the region, I'd maybe think you'd have a point. But you didn't make that point, so...
  15. NittanyWx
    Show your work.
  16. NittanyWx
    I'm beginning to think you don't know what you're talking about. On the other hand @bluewave does know his methodology even though I disagree with it and his conclusions right now. I don't think the tropical forcing is as hostile as he's making it out to be.
  17. NittanyWx
    I think your diagnosis of the forcing here is off. I see this as clear Nino forcing at the expense of the maritime continent, coinciding with +VP200 anomalies maritime continent. You've got about as clean of an eastward propagation in the VP signal as you'd like. If this doesn't work in traditional canonical fashion for more active (potentially snowier) purposes, it will likely be due to the erosion of source region combined with a poor placement/durability of high latitude blocking as a result of several factors discussed over the past few weeks in here. All valid, but not cleanly explained by tropical forcing alone. Right now and for the next week, however, you're getting the cleanest + 850 u-wind anomaly signal we've had so far this Nino with an eastward propagation of VP anomalies and a jet extension in the sub-tropics along with a fairly clean shut off of convection for about a week just west of the dateline (as shown in OLR anomalies too). Wheeler plots aside, those are the typical ingredients of a canonical back half Nino pattern from a tropical forcing/synoptics perspective. So if this doesn't work, I think you'll need to look at factors other than the tropics for why this split flow pattern did not deliver. I've got a few reasons ready and I'm not convinced this is going to offer much, but I don't agree with your assessment of tropical forcing right now.
  18. NittanyWx
    It's a fairly coherent 1 week period of E Pac to Central Am forcing while coinciding with subsidence over maritime continent, Pretty clean Nino all things considered. If this doesn't work, it's likely for reasons unrelated to tropical forcing, which is the drawback to using this methodology. To me it looks like a split-flow NIno look for a bit though.
  19. NittanyWx
    Please, for the love of God, look at hovmollers to diagnose forcing. Happy Sunday.
  20. NittanyWx
    Not accurate. Subsidence emerging in p7 for the next week or so. Strong -VP anoms/forcing in E Pac. If this busts warm, cant blame p7.
  21. NittanyWx
    Let me try to explain this a second time, becuase I'm not sure you're understanding what I'm saying. Those hovmoller charts are showing a +OLR anomaly in the phase 7 region for the 11-15 day window in response to an eastward propagation of the main negative VP200 anomaly. In laymans terms, the EC Ens today is showing progression. Now, the model is also trying to add some -VP anom noise late 11-15 day in those west/cpac regions too. But at a window where it's RMSE MJO forecast performance has been...not great. We've already had phase 8 physical forcing responses this year, the signal just wasn't particularly strong. That wasn't the case for phase 1/3 response, where we had a very nice and clean forcing for end December and early Jan...certainly that was shown at the VP200 level. Isolating out OLR:
  22. NittanyWx
    VP200, 850 u-wind and OLR all show convection and the expected forcing response eastward with a progressive MJO signal. There really isn't much debate here as to the progressive nature of tropical forcing. There is a lot of debate on whether this parlays into cold in the windows it's supposed to for early-mid Feb. IO convection is shut off for the time being.
  23. NittanyWx
    The VP signal for the MJO was and is a clear P-8-1 in Dec and it failed to produce expected results for reason's we've outlined in this forum in the past. A question I'm asking myself is whether the SPV/TPV decoupling actually allows wave breaking to do it's thing via jet retraction mid month. Think it's possible, but not yet totally sold on it. I still don't think we should be using wheeler plots as any sort of predictive basis for snow forecasting in this region... Your Hovmoller diagrams get you a much cleaner and disaggregated picture of the things that you would consider to matter from the tropical forcing perspective anyway.
  24. NittanyWx
    This is the warmest winter on record nationally Dec 1 to date (total HDD).
  25. NittanyWx
    As have I. And you know what has been observed in a fairly recent study? Weak vortex events leading to west pacific convection flaring 2 weeks later. A sign potentially the SPV was modulating the tropics and not the alternative and they went a step further to suggest tropo-strato interactions in the tropics themselves modulated MJO activity. Response of tropical convection over the western Pacific to stratospheric polar vortex during boreal winter - Wang - 2022 - International Journal of Climatology - Wiley Online Library And you know what I think? We're getting so far down the rabbit hole in trying to find any sort of signal or jam any sort of convective activity into the equation that we're losing the ability to use it in a forecast. I do know I can use strato-tropo coupling periods in a forecast though, and I did that this season.
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