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Holston_River_Rambler

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  1. Holston_River_Rambler
    So, I went to the SSWE Compendium Index (https://csl.noaa.gov/groups/csl8/sswcompendium/majorevents.html) and looked for all SSWE that occurred in La Ninas and between mid Dec and early Feb. There were six that matched those criteria. Before I post what I found, the overall implications are, IMO, not very helpful for figuring out how this one will go. The events of early Jan 1971 and early Jan 1985 look like they had the best outcome, if we are looking for a storm. The AMO was negative then, so those events may not have much bearing on how this one will play out. If the past four during the positive AMO (mid Dec. 1998; early Feb 2001; mid Jan 2006; late Jan 2009) are any indication, what we are probably looking at is some changes to high latitude blocking approximately 10 - 20 days after the event, and then a return to the base state a couple of weeks later. Here are images and gifs of the strat at the event as documented in the Index mentioned above, a gif of the H5 and MSLP patterns around the time of the SSWE and then around two weeks later, when changes to high latitude pattern became evident. Every event featured changes to the heights at high latitudes, but to me, it's unclear exactly how the SSWE is implicated (if at all) in those changes. In. other words, I'm not sure how much of those changes were just normal pattern evolution and how much they were connected to a SSWE. Apologies for the blinky images in some of the gifs. The NCEP reanalysis panels load a little slowly, so just doing a screen recording was the best way to get the max number of images to get a sense for the flow of the pattern before and after. Jan 1971: Pattern before: Pattern After: Jan 1985: Pattern before: Pattern after: Dec 1998: Pattern before: Pattern after: Feb 2001: Pattern before: Pattern after: Jan 2006: Pattern before: Pattern after: Jan 2009: Pattern before: Pattern after: I thought I'd look at the MJO too, by looking for precip. anomalies in the tropics.. No real surprises there, since all the above were La Ninas: Still not sure what I make of all this, but here it is, as a reference point, as we go forward. @John1122 any data for storms/ temps in some of those windows?
  2. Holston_River_Rambler
    Yeah. I just look at the SPV to see what’s up with it, not for cold or anything like that. IMO we are gonna have to just wait it out and see what happens after the “event” (whatever that turns out to be for the SPV). I’ll try to dig through some analogues tomorrow for a similar situation, but we should probably weight the 2019 one pretty heavily, given SSTs.
  3. Holston_River_Rambler
    The patterns the ensembles were spitting out for the 10 - 15 day range for the SSWE in 2018 - 19 look good. I can't remember if they ever materialized though: I feel like we got a nice arctic front and the "Dayton leeside micro low storm" that produced for some eastern areas (n. sevier and blount counties) I'll have to go back and look.
  4. Holston_River_Rambler
    I don't think the 18-19 one coupled and that was why it didn't do much. I could be misremembering though. Yeah, if this one happens like that one, it could just crank up the Nina base state. Isotherm and Griteater remain optimistic for January though, so I'll trust them and wait and see.
  5. Holston_River_Rambler
    Looking at Ventrice's research, it looks like this one is being generated over Siberia (like the one we don't like: 2018 - 2019). Compare Ventrice's images form 2019, to that EPS gif above, very, very similar. That one never coupled though with the troposphere though. Will this one?
  6. Holston_River_Rambler
    @Carvers Gap Butler actually has a nice plot to answer the timing question and she seems encouraged that this one might couple with the troposphere, unlike the one in 18 - 19 Here is the 12z Euro OP. Looks like it gets cranking around Jan 3 - 5.
  7. Holston_River_Rambler
    This is kinda what I've been looking for on Twitter (my gifs don't go back far enough to see the pattern from 17 - 18 or 18 - 19: Here are the key images from his presentation:
  8. Holston_River_Rambler
    Recent article (as in Dec. 2020) (no paywall) by Drs. Amy Butler and Daniela Domiesen on SSWEs and their tropospheric impacts https://www.nature.com/articles/s43247-020-00060-z There'll be a pop quiz on Monday, lol. I'll be honest, I haven't read it yet, but though some of us might be interested. I'll probably read it in the AM.
  9. Holston_River_Rambler
    In 18-19 the Jan SSW seemed to help fuel the convection of the MJO in the 4/5/6 areas. Hopefully, if there is a connection between the cooler temps at high altitudes in the tropics and enhanced convection, we can time it better just as some convection flares up over the western Pac areas: If it happened right now, and the above helps reignite convection, I'm not sure it wouldn't just sit over the areas it is now looks like mostly 5 to me: I think the strat. is a done deal now. Something is going to happen to mess with it. As to how it unfolds, whether or not it qualifies as a SSWE, whether or not there is a displacement or split, and if it helps NA pattern or not, those are the big questions. The 17-18 happened around mid Feb or so, and that one did result in a nice pattern, it just took a month for the eastern areas on North America to benefit from its repercussions, and by them we just had a grey, rainy, cold, spring. For now the Pac jet extension is coming and until we navigate that I think the ensembles will look nasty at times in the LR. That's not to say there isn't a chance of the storm we've been seeing for New Years, I don't mean to imply that at all. Just blah ensemble means like this: For reference and discussion (if any are interested in looking at them) here is the pattern in mid Feb 2018 that proceeded the SSW: ~A month later: A low can't cut, but it is a bit late in climo for us. I will try to dredge up some more of these type of gifs while we wait for the strat to do its thang. Maybe we can try to get a hint at what could happen.
  10. Holston_River_Rambler
    Frozen Head Chimney Top Trail: Looking towards Wartburg: Chimney Top (~3100'): Looking towards Lone Mountain: Saddle before Chimney Top: Chimney Top saddle trail: Ice Cliffs: About the same amount of snow I had. Less in places.
  11. Holston_River_Rambler
    Looks like Dan may have broken into the negative single digits this AM: Definitely some chilly spots with snow cover this AM: not too often the IR picks up snow cover in the purples in East TN
  12. Holston_River_Rambler
    6z GFS OP would be an ideal solution FMBY. The energy digs south and progresses through our longitude in a great way: If you've heard people say, "you have to get cold air and moisture to meet," this is a great way to get it. That NW to SE tilt the energy takes, helps throw that moisture back over the cold air. 6z GEFS (new version) more enthused for western areas, but still a lot of misses for everyone. Old 6z GEFS has some nice hits too. The UMKET has a really deep piece of energy that digs further south, but it turns negative too far west: The CMC and Euro are in the middle of these two. But I would say closer to the Ukie. Hopefully, if a similar set up happens again this week, western areas can benefit this time. EPS says nada.
  13. Holston_River_Rambler
    I'm finally getting some streamers up here in MoCo: I had forgotten how pretty fresh snow on top of old snow is
  14. Holston_River_Rambler
    For some reason the full gif didn’t load. The end looks even better! Some PNA action.
  15. Holston_River_Rambler
    EPS too
  16. Holston_River_Rambler
    EPS member 16 says Merry Christmas to TRI: HO HO HO
  17. Holston_River_Rambler
    Yeah, it just gets shredded by the bigger storm earlier, when that storm hits the big block and gets stuck. 0z overnight/ 12z yesterday (side by side, no less, a la Carver) I think with the Pac jet extension caused by the big Siberian high, having the zonal look from overnight is gonna be a risk until the jet snaps back after that extension. it's like a conveyer belt of energy getting cranked up and spitting out energy that has to be timed just right with the big NAO block. About the same number of EPS members have a storm around that time though, as compared to the 12z run, so something is still possible in that window. The 6z GFS (it's Christmas, so why not) shows a positive outcome to what might happen as the jet retracts: Some of the bad convection areas looking fiesty right now too: The 3D Strat vortex looking rough, so that can't be anything but good. No big split guaranteed and like others have said, no telling exactly how that would turn out, but so far it being under stress seems to have been good: Ensembles:
  18. Holston_River_Rambler
    One of those dollops doubled my snow while I was asleep, waiting on Sandy Claws!! 3.5 - 4 in a few choice places !!! glad to see Dandridge is ok!
  19. Holston_River_Rambler
    Oh yeah!:
  20. Holston_River_Rambler
    Snow dog: She decided it would be a good idea to go waller in the snow!
  21. Holston_River_Rambler
    It is such a cold/dry airmass, I was wondering how well those models progs would verify. I will take fine flakes!
  22. Holston_River_Rambler
    Thanks for the update, was curious about those radar returns.
  23. Holston_River_Rambler
    I know which house you are talking about. I grew up a few houses away, lived there from 1983 - 2007. One of my best friends lived in that house for a while. Good times on that road and the mountain for me!
  24. Holston_River_Rambler
    Not sure. I do think the mechanism that is generating the NW flow is the upper low and the lift that it creates in front of it is what's generating the snows currently over eastern areas. I suspect it's one or the other. Not a dumb question at all.
  25. Holston_River_Rambler
    Some of the long-awaited snow bands associated with the upper low and lapse rates are starting to develop over KY and Middle TN:
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