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vortex95

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    MD

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  1. vortex95
    That's a solid sign. One thing that can misleading -- cool, dreary, and stable-looking can make ppl think, "how can this 'go away' so fast and big svr occur?" Well, it does and can be quite dramatic. Wichita Falls TX was socked in stable ahead of the warm front on 4/10/1979, and then an F4 cut directly through the city for the costliest tor up to this time. Same thing in Windsor CO on 5/22/2008. This was an odd one b/c it occurred the late morning, moved NNW, and the storm formed in a a very narrow sweet spot of instability/shear ahead of a sfc low. See here: https://www.weather.gov/bou/TornadoMay22nd2008 Mean-looking! https://www.youtube.com/watch?v=GfYuT0oalXQ
  2. vortex95
    It loves to make giant convective blobs on its composite reflectivity fcst. Once it goes operational, and ppl use it more, I bet that will be a sig complaint, and they will address it. A big issue w/ mesoscale models now is that the more hires they get and more directly simulate the atmosphere processes, the challenge to get everything in balance goes up in a non-linear fashion. In other words, any small tweak to fix one issue can have big impacts to another part of the model.
  3. vortex95
    Yes, quite stable looking w/w a mid level deck (almost asperitas). However, there is instability above that, as evidenced by the sharp showery nature of the rain, Driving a short time ago, I'd literally hit a wall of rain, but the shafts are very narrow. Drove another 500 ft, and it would just stop! No vis reduction. And the rain was heavy not b/c of big drops, but the density was very high, so warm rain process and shows how tropical juiced things are! I did not like that the 12z HRRR showed almost nothing for the DC area this aftn, but the 13 and 14z runs bring it all back. Not quite as intense as say the 00 and 06z runs, but at this point, we'll just have to see how the mesoscale details work. Due to the rain and cloud cover, hard to tell if this is any real front across the region. Winds are all generally light S from the PA border and S. No real temp gradient either, all in the mid-upper 70s. No 80 until RIC and that just SE of there. Still early though. The AM convection is on schedule and modeled well.
  4. vortex95
    I am thinking the dew point advection will be enough in the aftn. They all show a finger of high CAPE (HRRR shows up to 4500, but that seems overdone, GFS and ECMWF have 2500 max) to n-cntrl VA, stopped just W of DC (really close, only about 20 mi W). So there is good CAPE available, just not widespread. It appears there will be a N-S warm or stationary front bisecting VA Sun aftn. Look at the HRRR fcst for 21z Sunday. That is quite a temp gradient, and such a boundary is ripe for tornadogenesis. Any storm crossing or latching on to such a boundary can go tornadic very quickly. Even on the cooler side, it can be favorable a short distance in b/c the cooler air is very shallow so a supercell is still effectively sfc-based.
  5. vortex95
    And it shows solid destabilization despite lots of clouds. You can do a lot more for CAPE by adding to the dew point than temp per deg. GFS has DCA 69 dew point at 15z up to 74 by 00z. Also it backs the sfc winds to SSE. This is w/ WNW winds at 500 so that's over 90 deg veering sfc-500. That should mean robust supercells. Speed shear is common here but good directional shear is not so this may be a best tor risk of the year so far Sunday.
  6. vortex95
    1030pm last night. Dang! Ton of CGs as well.
  7. vortex95
    18z RRFS is the same. Both models show more than one wave of storms after the AM convection. I like the significant sfc dew point advection tomorrow aftn over the region
  8. vortex95
    Yes, i agree. and yes, avoid social media w/ all its hype and gloom and doom rhetoric! Looking at radar, you'd think that Lala is easily a min hurricane, but it shows how things can be misleading. A less apparent mitigating factor is that Lala started out as a monsoonal system, so it already had a broad pressure field and center. Monsoonal TCs generally do not tighten up much, esp. for its inner core, so I think that why you have a clear eye feature on radar, but the winds are less than what you would expect. The eye is now apparent on IR, but it is very ragged and the convection is not smoothly banded around it. That indicates shear and dry air still present. Recon not since last night, so the one en route now will be interesting, but Doppler velocities suggest little change through 15z. The overall point I was conveying from the start is that Lala is not you typical TC, and had more against it than for from the start, so odds of RI were low and it intensity curve would not be like many TC evolution we see for one moving W in the deep tropics. These kind of details count. I see far too many "social-meteorologists" and hype-masters gloss over things and treat all TCs the same as if it is "one-size fits all." Nothing could be further from the truth! For example, I bet there are some out there that are saying, "radar shows a clear eye, and now there is an eye on satellite, why isn't it upgraded to a hurricane?!" And yes, I can see why. Say Lala was far at sea. In the absence of in situ recon data, going by satellite estimates alone, when an eye is present, even if ragged, that usually mean min hurricane strength (Dvorak Technique says this). But again, one needs to examine all data available and the details for a proper assessment. My hope contributing to this forum is point out the finer details of TCs and their nuances/idiosyncrasies b/c the variance from TC to TC can be very large.
  9. vortex95
    Classic low-top, high-based "squished CAPE" cell wider than tall! Cold at 500 does wonders! And the cell just reeks "unstable" w/ its chaotic congestus appearance. Like the "chaotic sky" when ACCAS is present. This is an ACCAS on steroids you could say!
  10. vortex95
    I don't think the AM convection Sunday will be a detriment for later. There is solid support for the aftn-eve w/ a 700/500 trof moving in. PWATs increase in the aftn to as high 2.5" on the GFS/ECMWF/NAM, and there is very good directional shear w/ nicely looped hodographs and strong veering 925/850 to 700/500. Wind fields 925-500 ramp up in the aftn to 35-40 kt at all these levels. So supercells likely and the 2% tor risk is warranted. Could see upgraded to 5% given the strength of the 925 winds (30 kt+ is excellent and we have it fcst as high as 40 kt). Everything moves steadily W to E, unlike the previous events that were NW to SE and that pushed all the moisture and boundary focus S, so solid recovery for instability after the AM convection is a good bet. FF threat, as noted, is there are well. RRFS is quite aggressive for cntrl and nrn VA showing up to 7.5" of rain. This model tends to overdo things, but 4" in some locations high prob IMHO.
  11. vortex95
    More for HVN area!
  12. vortex95
    NHC gives Lala 55 kt at 00z. Yes, the pressure is down 2 to 995 mb, but peak 700 mb FL winds are only 53 kt w/ max SFMR surface winds of 48 kt. Standard reduction for 700 winds to the surface and the SFMR winds are matched well here, so 50 kt seems more appropriate. The 2330z Dvorak analysis gives T3.0 which equals 45 kt. So the satellite signature is not 55 kt, which would be a T3.5. Satellite signature does still matter even when recon is present b/c recon can only sample a small part of the storm. Satellite gives a complete view. Also, the above was a manually-done Dvorak fix. The Automated Dvorak Technique (ADT) gives a T2.6, so that is even weaker. All these things go into what to assign a TC for intensity. Looking at the EIR loop, there is no real change in organization, and the deep convection is pulsing and not banded well. Loop attached, We all see the same data, so not arm-chairing here, just giving an objective meteorological analysis, and talking about the different tools and products one can use to make their own assessment, which is a good thing to do!
  13. vortex95
    Not sure which would do this first, but I know they would do it for different reasons! @CoastalWx would do it b/c he pines for snow, and @weatherwiz would b/c he is just happy getting hail! https://www.facebook.com/reel/1613750856948083 hailPHUN.mp4
  14. vortex95
    1601z SAR pass does not show a well-organized system (see attachment). Looks like there are two LLCCs and this large N-S gap of light winds and strong asymmetry. I don't know why NHC keeps saying, "conditions generally favorable." That is vague. Dry air and shear are an issue. CMISS 18z analysis showed 18 kt of westerly shear present. Lala was 50 kt/997mb at 03z and still is 50 kt/997mb at 21z. 2156z recon shows these values unchanged. Models still show an upper-level trough developing over the western Hawaiian Island as Lala gets close to the Big Island, so that is not "favorable" in an overall sense. NHC seems to be hedging higher and using persistence IMHO. One possible factor is that topographic convergence may tighten the wind field along the srn tip of the Big Island as gets close for 64 kt winds, but that's a local mesoscale factor not directly related to actual intensification of the TC synoptically. Topographic influences for winds are to be discarded for assigning actual TC intensity AFAIK. It is similar to discarding mesoscale higher winds from intense pulsing convection when shear is present for the TC (Bertha had this big time) or a transient mesovort in the eye. Still a significant impact on Hawaii, not downplaying that, just talking above about the finer details of meteorological analysis, which I hope some find informative.
  15. vortex95
    And it was only a MRGL day! 8/12 and 8/13 were excellent examples of how "only" has gen tstm and MRGL out can be deceptive or promote the @CoastalWx MEH! MRGL say nothing about how intense any given tstm will be. And you can having honkin' supercells no problem. I recall in April 2024, MRGL for NC/SC and one storm produced 4" stones in SC! The HVN MB?, in a general tstm area, yet we get a high-end wind gust. And the PWM area ydy as noted. But the actual svr reports are isolated/sct as shown on the SPC plot from 8/12 and 8/13. https://www.spc.noaa.gov/climo/reports/260812_rpts.gif https://www.spc.noaa.gov/climo/reports/260813_rpts.gif And now for today, suddenly a narrow gen tstms area gets upgraded to MRGL at 1630z. Decent 500 s/w and temps drop to -17 C at 500 (that is quite good for August - and ydy they were -14 to -15 C). When it's good, it's good (NW flow and cold temps aloft RULZ!!!) I don't want to hear any IMBY "I didn't get anything!" whining either!
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