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Holston_River_Rambler

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  1. Holston_River_Rambler
    I've been NAM'd with a flurry or three Sunday morning WOOTaSaurusREX:
  2. Holston_River_Rambler
    For those of you who want to see what they are talking about:
  3. Holston_River_Rambler
    For all you Knoxville peeps, Elkmont exchange is selling their on tap beer for $5 for half a gallon, if you buy a 4 pack of cans ($10, I think). Good deal for me. Got a gallon of Imperial Stout for 10 bucks. The only caveat, they give it to you in milk jugs, so it is NOT a good idea to lay them down in the back floorboard and drive back to MoCo. The car was full of wife, dogs, and groceries, so I had no other choice, lol. I made it back with about .75 gallons and a free Imperial Stout scent in my car!
  4. Holston_River_Rambler
    A (schmaybe) live scene from that HP in Siberia:
  5. Holston_River_Rambler
    I guess I should have been more specific. I don't mean to say that extratropical cyclone will be the world record, but just that that anticyclone/ cyclone combo is up in that rarified territory. Speaking of rarified... (the blocking John was talking about)
  6. Holston_River_Rambler
    Y'all may have seen Webb tweeting about the Aleutian low too, I think this is the one that is spawned by that high's descent. Wonder how low that LP will verify? The EPS mean is 928 and I think the overnight OP was 923. The 6z Euro best estimate is around 1070mb for the 1090+ HP: And it has continued to adjust lower with the Aleutians low: 0z: 6z: This is world record breaking stuff, up stream of us, and will continue to mess with the models until it resolves.
  7. Holston_River_Rambler
    Not sure if this is accurate or not, but wow:
  8. Holston_River_Rambler
    So I had my little attempt at analogues a couple of days ago, but Masiello did his own overnight: I chose to use the 15th panel is his series of tweets because that's where the analogues are looped. Def. worth a full read through as his research above is much more thorough and, well, he is Masiello. He didn't pay as much attention to ENSO state as compared to me (I only chose La Ninas and he focused more on antecedent conditions involving a Ural/Barents High and an Aleutian Low). I think his conclusions were fairly similar to mine: "Finally, here is the -5 to +35 day composite around the 3 SSW events of surface temperature anomalies. Southern Canada/CONUS in the composite do not significantly cool down until 20-30 days after SSW central date in these years." I was looking more for blocking at 500 mb and found that it usually happened 10 - 20 days after the SSWE and that would seem to correlate to his conclusion, since the blocking happening at H5 would probably precede the cold dropping down by a bit. Now I don't think I have anything on Masiello, but I am happy that I somehow came to a similar conclusion, whether by coincidence or not. His thread was also a good lesson for me in how to look for analogues and use them.
  9. Holston_River_Rambler
  10. Holston_River_Rambler
    Every time I see a split like this, reminds me of Super Mario Bros. 2
  11. Holston_River_Rambler
    We have to have the lightning and thunder for the Sunday system to work out, lol. On a more serious note, hopefully we can keep the .qpf in the ~3" or so range. Feels like it has the potential to bust high on rainfall somewhere in the TN Valley depending on where the preliminary boundary sets up as the storm develops. Let Arkansas have the monsoons this time.
  12. Holston_River_Rambler
    Fully caffeinated now, I think if anything the models are seeing a potential end to the Pac jet extension now. I think it's just too soon for them to see anything meaningful from the strat. Here's a gratuitous EPS gif, so it's not all GFS stuff:
  13. Holston_River_Rambler
    As an addendum to the post above, the strat. weenies on twitter seem worried about overnight and yesterday's trends, just as we would be worried about a NW trend. there seems to be some concern over the strength of wind reversals. Don't ask me why that matters. Don't know and don't care, until I can figure out precisely how it translates down to the pressure levels we care about. But, on that note, apparently there is a paper coming out examining the lag between a SSWE and it's evidence lower in the atmosphere:
  14. Holston_River_Rambler
    The 0z GFS shows how that could be the case, or maybe they are seeing the end of the Pac jet extension. The 500 mb anomaly map reminds me of the sorts of progressions I saw yesterday when making those gifs for NA's pattern after a SSWE, although it seems a little early to me: No real ridging over AK, but not real troughing either. Just kind of a relaxation of the flow there. Probably doesn't hurt that the Greenland block meander's westward too. I wish I understood more about how these things percolate down in the atmosphere. Here is the 0z GFS's depiction of the strat geopotential heights at at 10mb (using the GFS for these because it's A. easier for me right now and I have access to more of it's layers of the atmosphere and B. it's all out in fantasy land, so might as well use the GFS): 50mb: How that corresponds a bit lower down to winds at 100 mb: and 250 mb (over just NA because weathermodels doesn't offer a 250 mb N pole view): That Pac jet is like a whip, throwing off pieces of energy at us. But it kinda quietens down, at least to my eye, towards the end of that gif. But it is hard for me to see exactly how the strat is impacting the trop. Maybe some of you can see something in those gifs I'm missing. Just looking at the MSLP anomalies, it makes me think that maybe this big cyclone in the N. Pac, in part triggered by the descent of the Siberian high, has to run its course too, before we can try to get the Pac back to something that is workable. You can see a big cyclone spawn near Japan as the high descends over China and then the cyclone keeps that gyre over AK going. I don't know much about the E. Asia rule stuff, but that would also seem to suggest the possibility for an east coast storm in a couple of weeks? You can actually kind of see that at the end of the gif.
  15. Holston_River_Rambler
    May be time for our annual monsoon to pick up:
  16. Holston_River_Rambler
    Of course this could all just be the same pattern we've dealt with already this winter. Extended looks bad for a bit (esp. Pacific), then improves as things get closer in time. Or La Nina could be starting to flex more. That image griteater posted yesterday of the last months OLR average was pretty damning.
  17. Holston_River_Rambler
    The more I think about it, the more I think the SSWE mess is just a roll of the dice, with those dice slightly weighted to fall in the favor of Eurasia. Not really anything we didn't already know, if we start with that premise and go forward. Not sure I really profited from all that gif making and analogue looking earlier this AM. Maybe I'll feel differently later though. I guess I do see some things to watch out for as it unfolds: 1) Watch the tropical convection. If it does indeed set up in the MC and the SSWE helps fuel it by cooling the upper parts of the troposphere, that would be bad. If however, it gets going more in the Western Pac, that would be good. 2) It will probably take 10 - 20 days for any High latitude blocking to happen, once the SSWE event occurs, and models will likely struggle a lot. I guess the problem I'm having with this, is I could have just taken out the strat. stuff and made the same statements above, and they would have been equally valid: 1) watch tropical convection 2) models will struggle with blocky scenarios. Thank you for the link to that, I think it will be helpful for me to try and figure out how to look for the signs of SSWE future. Seems to me, and I may be reading it incorrectly, that it is geared more toward subseasonal predictability of the SSWE in NWP, rather than the atmospheric repercussions once they happen.
  18. 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?
  19. 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.
  20. 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.
  21. 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.
  22. 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?
  23. 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.
  24. 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:
  25. 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.
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