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Ground Scouring

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  • Birthday 08/25/1992

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  1. I think this event will end up verifying on the “low” side of current expectations. The two most recent GFS runs have shifted toward a higher-amplitude, blockier setup due to their resolving the situation in the North Pacific (Gulf of Alaska) better. This means that the downstream circulation over the Ozark region will have a tendency to become “pinched” due to enhanced shortwave ridging over the Great Lakes. In turn, this implies a surging cold front along with mid-level winds paralleling the surface boundary, especially toward the northern half of the warm sector. I think we may see a few supercells capable of producing a couple of strong tornadoes, but these will likely be localised along boundaries from eastern MS eastward across the southern two-thirds of AL. Most of this event should consist of QLCS and bows, with some isolated, discrete events along boundaries, as mentioned. One thing I have noticed is that “major” events since 2011–13 have ended up underperforming in terms of either severity and/or aerial coverage, perhaps due to the warming Pacific basin, the slowing AMOC, and the +PMM signature; the warmer Pacific basin and emergent -AMO over time have tended to hinder low-amplitude, progressive setups, regardless of temporary shifts toward -ENSO/-PDO.
  2. There does not seem to be sufficient, specific evidence, as opposed to speculative notion(s), as of now to call the independent existence of the AMO cycle into doubt. Spectral AMO peaks clearly exist even in the study by Mann et al. If anything, climate change and the AMO(C) may be inversely correlated, given that a weaker AMOC due to AGW → weaker +AMO signal. The freshening of the North Atlantic will likely lead to an early—that is, premature—onset of the next -AMO period, and some signs, namely temperature and salinity, are that this began in 2013–14, although overall Atlantic TC activity has yet to fully respond accordingly. I think AGW is likely leading to shorter +AMO periods over time and is likely heralding the next -AMO within five to ten years.
  3. Could climate change weaken the correlation between ENSO and severe weather as the Pacific warms?
  4. The problem with renewables is that they are highly inefficient in terms of energy output and actually add to the carbon footprint via expensive, environmentally destructive practices, e.g., mining for rare-earth metals. The more one invests in, say, solar panels and wind turbines, the more multinational corporations take over vast swaths of the Third World, while still adding vastly more to the carbon footprint than renewables eliminate, owing to the productive processes involved in manufacturing renewables. Unfortunately, Western discourse on this topic is dominated by a false dichotomy between conventional fossil fuels and a limited, pre-selected array of renewables. Intelligent countries such as China, South Korea, and Pakistan are heavily investing in building new nuclear plants and upgrading their old ones. Nuclear power is both clean and energy efficient. We as a species already have the tools in place to store nuclear waste far more effectively than we did in the recent past. Japan’s disaster in 2011 was due to neglect and negligence, not nuclear power itself. Plus, many governments and semi-private organisations likely have far more efficient, black-budget energy sources than are currently marketable in public. Free energy is not sci-fi, but very viable. This does not even cover the potential for abiotic sources to emerge. Unfortunately, the fossil-fuel monopolies have effectively suppressed information about this and other threats to their power, including nuclear. Pressure from the fossil-fuel lobbies has generated hysteria about the supposed dangers of nuclear energy while performing “bait-and-switch” for the polluters via their pseudo-“‘Green’ New Deal” based on fossil-fuel-consuming renewables.
  5. Part of the problem is that the Pacific basin is the largest on the planet and thus is warming faster overall than the other basins due to climatic forcing.
  6. Is there any overriding, large-scale, climatic forcing that is likely behind this? It definitely seems to be a theme, regardless of other factors.
  7. Models continue to advertise a potentially significant threat around 30 Jan–1 Feb, with the 12Z deterministic ECMWF and the 12Z EPS showing one of the warmest low-level air masses since 26 Dec 2015 (the date of the Garland, TX, EF4 tornado) over the southern High Plains for multiple days. In fact, even the EPS mean shows 15°C 850-mb temperatures reaching as far north as the TX/OK panhandles on at least two of the days that I mentioned. One important key is the relatively low amplitude of the upcoming pattern, with its lack of significant cold intrusions, which not only may prevent heights from rising too much ahead of any ejecting disturbance, but also allows southwesterly low-level flow to advect richer instability (as well as a noticeable if not strong elevated mixed layer, which is surprising given the subtropical jet) north from the Mexican plateau. The tongue of greatest instability is likely to be at least a bit narrower than projected at this point, but the fact that we are talking about EMLs and a potentially significant southern High Plains threat in a potent El Niño says a lot. For reference:
  8. Both the EPS and the GEFS are signaling a major long-range pattern shift toward the the end of January and the first week of February (especially around 28 Jan–1 Feb), with a restrengthening of the polar vortex and at least a transient +NAO/–EPO/–PNA period taking hold. Even at this range, models are indicating that the polar jet will take over as the dominant stream with strong hints of multiple shortwave impulses intruding into the Pacific Northwest, likely inducing lee cyclogenesis east of the Rockies. Details regarding ejection and overall evolution are obviously too early to ascertain, but the overall trend toward a more zonal look/longer wavelengths favors a Southeast ridge with likely favorable moisture vectors out of the Caribbean, setting up a potentially decent return flow over the southern High Plains for a few days in advance of any potential ejecting disturbance. There aren't many analogs from strong El Niño events since 1950, but an interesting one is 26 Feb 1958, which was somewhat similar synoptic-wise and featured several significant tornadoes across LA and MS. An interesting difference is that this case may also extend the opportunity for severe weather to the southern High Plains.
  9. Regarding the subtropical jet and its effect on the EML in recent events, where should I look to find the STJ? Is it at 200 mb, 500 mb, 700 mb? Didn’t major Plains events like 4 May 2003 feature a STJ influence? Also, if the EML is at 700 mb and comes from the Sonoran region of northern Mexico, then why is a STJ coming from N Mexico a problem? Is the STJ within the same level as the EML or not? Can, say, a 500-mb STJ affect the quality of the EML at lower levels? If so, how? Maybe I am totally wrong, but I would like to gain some meteorological understanding.
  10. Since the ECMWF did not close it off too substantially at 96 hours, does that suggest that it has an edge over the GFS within that range, especially given the ECMWF's usual tendency to cut off lows too much/early? I would add that the GFS seems to be trending toward the ECMWF's evolution by Saturday, is it not?
  11. Regarding the first point, I think my flaw was that I made an outbreak with several tornadoes seem insignificant on the whole, when I was only referring to the original outbreak area in N TX and parts of OK (and even there I was more wrong than right). There turned out to be more visible tornadoes and storm structures than I anticipated, not to mention numerous significant tornadoes (with a count still rising) that definitely caused substantial damage and loss of life. I also should have not overlooked the threat in CO/KS, where there were also significant, long-tracked supercells with strong tornadoes. I really don't know enough to be judging events in progress; even people with more experience and actual background would struggle with a difficult forecasting situation like that which existed on this past Saturday. I can come across as being unwilling to listen, and in fact I am too stubborn and prone to emotional/forecasting swings in many situations. I need to try better/harder to sit back, read, and watch, but sometimes I feel left out when serious questions don't get answered (sometimes understandably, based on my behavior). Regarding this coming Saturday: I must say that the 12Z ECMWF solution, taken ad verbatim, would almost certainly result in a major, quite possibly historic severe outbreak over a wide area, extending from OK/southern KS in the south to NE/SD in the north. What is critically important is that the ECMWF, as early as 96 hours, already begins advection of the first solid EML of the year, with a plume of high-quality inversion spreading northeastward from the Sonoran region over the southern Plains. More than a day and a half before the arrival of the deepening surface low on Saturday, there is already a robust EML in place over the southern Plains, and this EML remains in place through most of early Saturday due to the overall neutral tilt of the 700-mb trough. Moreover, there will be two full days of deep Gulf moisture spreading north, with a fairly strong low-level jet in place by 72 hours. As for the trough itself, the ECMWF has shown a notable shift toward a much broader, consolidated mid-level trough at 96 hours—an important trend as we get within the short range, the ECMWF’s kill zone. If the set-up at 96 hours verifies, then it will automatically have a significant impact by the time the trough ejects on Saturday. Shear is absolutely off the charts for mid May; even considering the ECMWF’s tendency to overdo the strength of the mid-level jet maximum, the pattern depicted would bring H5 winds of at least 55-60 kt into the warm sector Saturday, particularly over OK and southern KS, as a secondary surface low develops over the TX Panhandle. The orientation of the mid-level trough would imply fairly robust to strong backing of the surface winds all along and east of the dry line, extending well north into NE/SD. Such a set-up might also favor dry-line bulges (meaning low-level convergence as the surface low deepens) in OK and southern KS, where the best shear/instability combination seems to be present on the run. There is also no doubt that instability would be strong to very strong if the EML verifies as depicted. The very wide warm sector would also suggest a secondary severe threat along the retreating warm front in NE/SD (although the eventual location/evolution such a threat is more contingent on mesoscale details, such as early convection). All in all, the pattern on the ECMWF shows mid- to late-April dynamics juxtaposed with mid-May thermodynamics. In fact, it does so to an extent that I can’t recall in any previous Plains outbreak on or after 15 May. The overall pattern reminds me a lot of the late-May 1917 sequence, with a series of southern impulses gradually giving way to multiple large-scale, ejecting disturbances. If trends continue, I think that we may be looking at something very special this coming Saturday (and quite possibly Sunday over the Ozarks/upper MS Valley/upper Midwest, depending on how overnight convection and the upper-air pattern evolve).
  12. For the record, what do you think is likely to happen this coming Saturday? Honestly, I'd be more interested in your meteorological reasoning than another retort. You could also argue with anyone else who has been (justly) noting the lack of an EML, negative tilts/southerly tracks, etc. Argue with Brett or Jim (wxmann), for instance. A little fairness might be appropriate here.
  13. It might well come to nothing if we don't have a good EML. The trend toward a neutral/negative tilt with a "pinched" trough (i.e., one farther south with time) is not encouraging, as that would discourage a good EML from emanating over the warm sector. Anyway, we don't need more HP cells causing havoc for both communities and chasers.
  14. Even three years later, reading the accounts, and especially this book, never ceases to move me. The entire rebuilding process is like a model and a case study to be compared to those of other cities recovering after disasters. Probably the network of local businesses and the diversity of Joplin's demographics played a significant role in fostering the recovery--better than in, say, other areas that suffered comparable disasters. The bottom-up approach that worked so well in Joplin seems more plausible in a city of its size and composition than in a dense metro area like New York City.
  15. Please try to look up the correlation, if any, between the March QBO phase and landfalls based upon similar past evolutions. I would be highly interested. Keep up the great research, as always.
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