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Holston_River_Rambler

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  1. Holston_River_Rambler
    EPS agrees with the operational in that there is a big 500mb trough over the eastern US around next Wednesday, but there seems to me to be a wide spread in the individual placements of multiple pieces of energy at 500 mb in that trough across the EPS members. If you thought the last one looked complicated (not the nice NW flow event, but the long suffering storm track we consummated last week) you ain't seen nothing yet. GEFS and GEPS 500 mb geopotential height means seem to agree with EPS means. I'm just too lazy and worn out right now to dig much deeper in these other ensembles' individual members, but the ops show a wide spread of energy pieces across the eastern US. I have included an image of the GFS of 500 mb relative vorticity at the beginning of the evolution of this storm just to illustrate how much energy (numbers 1-6) is rotating and interacting. I know most of you know how to read this, but there maybe someone lurking here like I did who might like to see what I'm talking about. Also, I don't necessarily favor the GFS here, but just want to show how complicated all this is. "Just in time..." as Jeff has said is not good for lower elevations and southern areas even in mid winter. What a weird set up though! All major models have primary surface low below 1000mb meandering across the TN Valley and then dying in southern WV as it transfers to the coast. That would always scream to me (in every situation I can think of aside from there being an exceedingly cold antecedent air mass in place) horrible set up for any type of winter weather in our area. I think it looks really complicated and marginal for areas outside of maybe 2000 feet and up and especially southern areas. And that's if it works out at a 5 day lead as it has been modeled over the past couple of days. Bottom line for me: At this point I'm burnt out for winter, but I thought I'd give it a day yesterday and see how things began to break. Not in any way hopeful for any type of winter in my neck of the woods, but wouldn't mind a flake or two if its going to be cloudy and cool. It also seems like such an unusual evolution for a storm if it occurs, that it might turn out to have a surprise or two for someone at elevation and NE as most of these upper lows seem to have lately, even if it doesn't have one for me. Complicated and difficult things interest me, and the whole evolution just seems that way to me. High fail potential, even if it is just for a 500 mb setup = high learning potential. Also there seems to be some talk in some of the other subforums that this may be a bigger storm further north that helps boot out the -NAO and usher in a more significant pattern change. I think we can all get behind that at this point. By the by John, I do not mean this as a direct response to anything you've posted. My interest has been piqued though, so these are just my overall thoughts on the set up.
  2. Holston_River_Rambler
    I don't know how much moisture will be left by tomorrow around 7 AM, but a 18z, NAM 3k sounding over SW VA (from Tropical Tidbits) is showing a DGZ between 850 and 950 mb, but an associated dry layer. Sounds pretty low though and maybe able to squeeze that last bit of moisture out for NE sections.
  3. Holston_River_Rambler
    Looking at the EPS at 240, one thing that intrigues me is that the renewed -NAO (if it verifies) seems to be a slightly different critter than the one we just saw. The recent one was driven by the strat and seemed to retrograde as part of a general pattern across the North Atlantic. While it was very strong, if I remember correctly it also was limited to northern latitudes for most of its life cycle. (See my image on page 79 of the Winter Speculation Thread for the recent -NAO) This one seems to have more of a equator-ward connection. At this point not really chasing any snow, but more interested in storm track for future winters. Does the type of NAO have a correlation to a storm track? If there were a fuller latitude Atlantic block, does it change things up as it weakens? If we can get something like what the 10 day EPS shows, let's see.
  4. Holston_River_Rambler
    3k NAM and RGEM are bullish with these snow showers and both want to show them coming in overnight which will probably help the areas normally favored. I've been surprised in Knoxville a few times by a good overnight snow shower (a decent dusting). Energy looks nice and the fetch is from lake Superior onto Lake Michigan and then SSE.
  5. Holston_River_Rambler
    Interesting find from a meteorologist in the MA forum regarding how the WPC generates their snowfall and other winter precip types probability forecasts: http://www.wpc.ncep.noaa.gov/pwpf/about_pwpf_products.shtml
  6. Holston_River_Rambler
    Seeing the link Carvers Gap posted in the speculation thread, made me remember a storm I was always curious about. I was in Kingsport at DB at the time and remember a what was probably a weird upper low that just spun over East TN. I remember the radar showing snow everywhere but Kingsport and the analogue of 3/26/99 seems to fit that bill. I wasn't into weather as much at the time, but enough to notice the weirdness of it. Any one have any memories of that one?
  7. Holston_River_Rambler
    And I thought my waterfalls coming out of Cumberland county were full before: Sorry should have included the scale, 4.80 inches is the white
  8. Holston_River_Rambler
    Dates used for the above composite: 2-9-58 1-1-96 3-5-93 1-22-66 12-17-66 12-19-69 1-14-78 1-12-79 1-14-87 2-06-60 12-26-86 12-16-63 12-25-70 1-1-88 1-25-96 12-10-73 1-6-78
  9. Holston_River_Rambler
    One last hurrah on this for a bit, unless asked for more.. I will be happy to do it for any all future months (with John's awesome help of course)! Disclaimer out of the way, I went through the KU book at just put in dates for one week before every storm from the 20th century that looked like it had a great track, or produced a lot of snow for most of the forum area. I mostly aimed for Miller As, since, for me anyway in Knoxville (1996 was good in Kingsport when I lived there though), Miller Bs have been awful. (Jan. 2016 was rough for me in Knoxville, though I watched it with y'all). There was one year that had a storm with an awesome track that their book showed as rain, but I left it in since the track was great and may have produced a different result given different boundary layer conditions. I also put in Jan. 1996, since it was epic for some of us. I couldn't add in anything after 2012, because of the data restrictions on the site, so I couldn't add my two favorite Knoxville storm years, Feb. 2014 and 2015. Without further ado, 500 mb anomalies in North America one week before some of our best storms:
  10. Holston_River_Rambler
    I'll also add this. As disheartening as it is, after looking at the NAO data today and having just looked at dates for big storms over the past few days, I think we want more mediocre NAO values. Some of the big dates had -NAOs, but most were under -1.0. But I think we've all agreed that it is as the big block decays that we get our chance(s). On the other hand there were no -NAOs below 3.0 in the winter in the period of record and I think only two on record at all, for any month. If this one goes that low who's to say what the outcome is. I also don't like the look of the little ridge poking up on that first image. Looks familiar to what is being modeled with this persistent mid continent ridge that connects to that NAO.
  11. Holston_River_Rambler
    Alright, I chose dates that seemed to me to have the worst outcome (rain, no snow, warm) and I threw in a few others on John's list that I found to have also happened after a recorded SSW. For the ones that happened after a SSW I have added ENSO state and QBO since it was included in the SSW information and I thought, why not, and so then went back and added ENSO state and QBO for the others. I will also go back and edit my posts for the big snows to include ENSO state and QBO data so they match these. Here are my dates: 3-28-51: ENSO neutral; E QBO 3-12-54: had been El Nino, but in the FMA timeframe, dropped off quickly to 0.0; E QBO 3-6-69: SSW event on 13 March; El Nino; E QBO 3-30-70: ENSO Neutral; E QBO 3-30-71: SSW event 20 March; La Nina; E QBO 3-24-77: El Nino transitioning to Neutral; E QBO 3-20-80: El Nino transitioning to Neutral; E QBO 3-18-81: SSW event 4 March; ENSO Neutral; W QBO 3-26-81: ENSO Neutral; W QBO 3-1-2001: SSW event Feb 11; La Nina; E QBO To be honest it doesn't seem like any of those dates could have been big time snow producers for valley locations (could be wrong) and I will also add that many of the "worst" outcomes that I picked were at the end of March, so climo. may have played a part in those outcomes. I have attached images of composites of 500mb geopotential height anomalies for the time the -1.0 NAO began (top image), then the progression by one week (middle), and then by two weeks (last image).
  12. Holston_River_Rambler
    So, to be fair, I thought it might also be useful to look at big -NAOs (-1.0 or higher) that failed to produce anything in March. I went through the NAO data on ftp://ftp.cpc.ncep.noaa.gov/cwlinks/norm.daily.nao.index.b500101.current.ascii and searched for values or -1.0 or higher. Below are my results: -1 or higher 3-10-51 3-28-51 3-27-52 3-12-54 3-6-58/ 3-21-58 3-1-62 (almost the whole month lower than -1.0) 3-6-69 3-30-70 3-30-71 3-28-75 3-24-77 3-18-79 3-20-80 3-18-81 3-26-81 3-1-2001 3-11-2005 3-1-06 3-10-2010 3-24-2011 3-21-2013 -2 or higher 2-13-78 (only one that was close to the dates we're looking for; there were some April ones, but that'e getting pretty late in the season) -3 or higher None in the winter If John is willing, I thought it might be useful to look at his family records for a couple weeks after these dates to see if there were storms. If no storm, then I would like to build a composite for those dates as well so we can see what sort of pattern with a -NAO might not produce winter weather.
  13. Holston_River_Rambler
    So this AM I thought it might be fun to add to the above image by looking at how we got to those dates. We often see analogues for the date of a particular storm, but not the weeks before and if many storms come at the end of major blocking, it might be a good idea to check out how things looked before. Below are the images for one week (top) and then two weeks (bottom) before the events above. It seems to me the NAO snaps and holds the ball while the Pacific finally kicks it.
  14. Holston_River_Rambler
    I know I had two other links, but THIS is the correct link for the daily reanalysis page: https://www.esrl.noaa.gov/psd/cgi-bin/data/composites/plot20thc.day.v2.pl
  15. Holston_River_Rambler
    Alright, I have the first one. Below are the dates I picked. I started with the biggest ones on John's list and added ones I found in the KU book this AM. I have figured out how to work the system better and found the correct link (in the links thread) to the daily 20th century reanalysis data, so am happy to plug any combination in y'all want! 3-2-1942: No ENSO data; No QBO data 3-1-27: same as above 3-17-35 same as above 3-12-93: ENSO Neutral; W QBO 3-24-40: No data for either ENSO or QBO 3-1-54: EL Nino transitioning to Neutral; E QBO 3-2-60: ENSO Neutral; W transitioning to East based QBO 3-9-60: same as above 3-14-60: same as above 3-3-80: El Nino transitioning to neutral; E QBO 3-7-96: La Nina; E QBO 3-6-1992: El Nino; E QBO
  16. Holston_River_Rambler
    Sounds good. We can always start with that and see what happens. Then I can try to dig into newspapers in the area I mentioned yesterday. Found a good online source for Knox News going back to the 1800s, but still digging for others places. To be fair I didn't have as much time as I thought I would today, but its a process and every bit helps.
  17. Holston_River_Rambler
    So that analogue website has a limited number of data entry points, so I have to pick a few from John's list. I thought maybe try Miller A and B events first, since they would have the potential to impact more of us than NW flows, but thought I'd see what y'all thought.
  18. Holston_River_Rambler
  19. Holston_River_Rambler
    I went ahead and looked through the KU book and have a list if storms that look to have impacted the TN Valley. I will add to it as I get more dates from y’all or other research. The KU maps typically show the whole Eastern CONUS, so I was able to see which of their storms impacted us. Some caveats though: 1. This is not intended to be a full list of everything just yet. Their book is aimed at Northeast urban corridor storms so southern sliders aren’t in it. I have also added a few extra already. I mainly want to get some of these dates out there so people with more knowledge of local climates can add to it or tell me “Hey, that one didn’t do much here”. I will go back through this thread later today and add the storms all of you have put into it already. 2. The KU larger maps are at low resolution so our microclimates in the high and low elevations may have had dramatic impacts not reflected in the book 3. I know we had talked about just doing March, but I just put them all in here for future reference. I see people talking about “changing wavelengths” in Spring and am not sure exactly what that means, but I suspect it means many of these storms may not be helpful as analogues. 4. I tried to look for uncomplicated Miller As that affected parts of the area. Some Miller Bs were included if they looked like they may have produced snow for some of the area (example, January 1965). I also live in the Great Eastern Valley so I may have excluded some storms just because I naturally key in on that area. If you have one that affected you and you want me to add it, let me know. 5. I tried to go by the start date listed in the KU book, but if we are going to plug these into the analogue generator I’m not sure what dates are best since we’re looking for 500mb patterns, not sensible weather. November events: 22 November 1950 December events: 24 December 1966 25 December 1969 23 December 1963 31 December 1970 16 December 1973 January Events: 5 January 1988 22 January 1966 21 January 1987 27 January 1922 23 January 1935 23 January 1940 11 January 1964 29 January 1966 18 January 1978 21 January 1987 25 January 1987? Mixing issues 5 January 1988 22 January 1966 21 January 1987 27 January 1922 23 January 1935 23 January 1940 11 January 1964 29 January 1966 18 January 1978 21 January 1987 25 January 1987? Mixing issues 16 Jan 1965 14 January 1982 7 January 1988 13 January 1978 February events 13 February 1960 11 February 1899 15 February 1900 7 February 1907 20 February 1921 21 February 1929 7 February 1936 20 February 1947 (western areas) 15 February 1958 13 February 1960 19 February 1979 2 February 1996 15 February 1996 March events March 3 1980 March 7 1996 March 13 1993 6 March 1932 18 March 1958 (close miss to east) 2 March 1960 2 March 1994 (Interesting track, but looked to be cone of those rare rain to snow storms that worked) 14 March 1999 (looked dynamic but rainy) April events April 1987
  20. Holston_River_Rambler
    In regards the the winter of 95-96, I think most people remember January and after, but in Kingsport I remember a clipper type of system around Dec. 9, 1995? (not sure I could tell you the difference between types of systems then, but the track seems to have been out of the N. plains and across TN). Greatest, most epic clipper in history for me! I think I got 6-9" at my house in Kingsport and for my lifetime, at least within my memory, that was the best December snow.
  21. Holston_River_Rambler
    Kind of an other side of the same coin question here, but there is an epic fail storm that I've always wanted to ask y'all about. I can't remember the actual date, so I was wondering if any of you did. It must have been between 94 and 99 since I had begun to watch the Weather Channel after 93 and got out of that after 2000. (I used to leave it on, volume down, while I slept and would love to wake up at 2-3 am sometimes and hear some of the crazier shenanigans late night on air.) Anyway I would watch the 5 day business planner and sometimes you'd see snow at day 5 and I'd then track it (just by watching the snow icon each day) until it was on the local on the 8s or whatever that was called when there was just music and no voice. I had no knowledge of models or anything like that then, I just thought they updated the forecast around or after 2 AM and 2 PM every day. Well if those snows made it to the first night on the local on the 8s (12 hours off) I thought I could pretty much bet on what they were forecasting. There was one night I went to sleep and the forecast was something like "Snow. Heavy at times. Accumulations of 8-12 inches possible". I figured if I didn't 8-12, well 6 would probably be ok. Woke up to nothing. I turned on the Weather Channel and remember their meteorologist Bruce Edwards saying something like "Well we were expecting this moisture to come north and it just didn't happen". {**Please note I'm not blaming him here or grumping, just rehearsing my experiences. This happened nearly 20 years ago and that would be crazy**}. Knowing what I do now, it sounds to me like Gulf convection cut off the moisture or something, but it always stuck with me how that one busted, but I can't remember what or when that happened. I was living in Kingsport at the time.
  22. Holston_River_Rambler
    One of my most distinct memories from that time and my entire youth (I was 10) was watching Johnny Wood on WCYB stand in front of a radar map, gesturing too a blob of precip in Texas and saying something like: "I know a lot of these seems to have missed us this year, but it doesn't look like this one is going to". Good times and thundersnow!
  23. Holston_River_Rambler
    While checking out twitter today, I came across this link to a Compendium of SSW data sets: https://www.esrl.noaa.gov/csd/groups/csd8/sswcompendium/
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