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Windspeed

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Everything posted by Windspeed

  1. Good lord, so much activity going on world-wide (despite the usual suspect WPAC), I can't keep up. Of course, work...
  2. Shear. Development? Sure. But a long duration hurricane? Very unsure.. A few clicks west, even now, and this vortex gets shredded. And any amount of poor modeling of that shear axis might still not account for it getting shredded tomorrow. For a hurricane, Tammy has been living on the edge. It has remained just barely east of some very strong shear values and has kept pulsing just enough to maintain its open eyewall. Even the more NNW turn likely kept the mid-level circulation from being decapitated tonight. I never expected Tammy to become a hurricane, and I definitely didn't think it would remain one this long. That being said, the title could use a bit of an edit, @Ed, snow and hurricane fan
  3. Tammy has made a direct hit on the island of Barbuda. An official landfall as well. Edit: The hospital in Barbuda recorded 78 kt sustained winds in the eyewall. Unofficial, of course; I am sure the station anemometer will need to be checked. Tammy has a very small core, but clearly, the LLC vorticity maximum remains healthy. Additionally, it is riding against the ridge to its NW. The gradient is strong, so I am not surprised at the wind reading if it is verified. Especially if elevated.
  4. A rare case of low shear over the NIO with the TC positioned perfectly under vast anticyclonic flow aloft. This may very well become a Category 4 on Sunday local time there. Expected to make landfall near the Yemen-Oman border and most likely major flooding for both countries.
  5. ECMWF wants Tammy to miss the trough and stall just north of Puerto Rico. It would likely be in a sheared environment there while in a blocked steering flow. The GFS still allows the trough to capture Tammy and bring it SE of Bermuda, then leaves it behind. The GFS does place Tammy in a better environment for intensification as it moves N, prior to a being left behind, however. Some of the TC models even show a major hurricane, though I'm not sure I buy that.
  6. Wow, didn't expect the TC to reach hurricane intensity with shear in place. May be a short-term classification.
  7. Look at what 24 hours can do to modeling. Nearly everything is trending down in intensity guidance for 94L. Shear and subsidence are being picked up, and the ensembles look much less enthusiastic about a well organized TC near or NE of the Lesser Antilles. We may still very well get a named TC threatening the Leewards, but less likely to be a formidable hurricane.
  8. Two camps diverge around day three. However, it is important to note that the GFS struggles with developement of 94L despite the potential favorable setup that may be in place. The ECMWF and CMC both like and pick up on development. Clearly, the EPS suites show multiple scenarios of a hurricane traversing the Lesser Antilles. The camps that split do so over differences in modeling of the mid-level steering flow between a stronger versus weaker ridge just north of the MDR. Also, whether the placement of a ULL being in a favorable position to ventilate versus impact on motion of the potential TC. If you split hairs, you get a strong TS near the NE Antilles. Obviously, a stronger ridge combined with a stronger hurricane gives us all the EPS members screaming major impacts from Barbados to Puerto Rico. It's still quite early, though. The GFS/GEFS camps could quickly swing towards the Euro and Canadian solutions in the coming days, or vice versa. OHC is plenty high in the western MDR for a strong hurricane. Just need to watch for atmospheric conditions and any potential mid-level shear.
  9. Need to watch placement of the ridge. This might actually get driven into the E. Caribbean.
  10. Not so sure. Mid-level cloudfill in the eye at the timing of landfall may not matter. A product of shear, but might've been too late before induced weakening. The eyewall was pretty intense and intact. Just bad timing for landfall.
  11. Interesting to note that the upper-level shear values over Lidia are very high based on satellite analysis. However, notice how there is a weak region of the mid-level shear pivoting with the circulation. Dead giveaway that Lidia's forward motion within the circulation is remaining stacked due to mid-level flow and low-level flow swinging ENE with the trough. It's put that same core in a region of intense divergence aloft; ventilation for high instability. Lucky for RI of the TC, unlucky for those at landfall point.
  12. Impressive lightning currently around the eyewall. Pretty explosive intensification at the worst time. Lidia is a compact hurricane however. Should be a small region of hurricane force winds, though that will obviously be intense, especially with the abrupt rise in elevation for whoever or whatever is at that point inland.
  13. Forecast looks a lot more confident since last night. Not really much to add. Bermuda may get some nastiness, but nothing they can't handle. Phasing with the low could impact Maine, however.
  14. The low-level easterly steering flow in Philippe's locale isn't that strong. Due in part to Rina moving north in a pseudo-Fujiwara motion and also weakening ridge and trades. This has allowed for two critical developments. 1) Though mid-to-upper westerly flow has kept shear in place, the LLC has never been allowed to fully outrun and dissipate. Convection has built back repeatedly or just close enough to sustain the surface vorticity maximum. But the vortex has never aligned or stacked. So the weak low-level steering flow keeps the LLC moving west albeit slowly. 2) Time. The longer it takes for the TC to remain weak, the longer it will take to feel a deeper southerly flow and weakness in the ridge. This allows the downstream pattern to evolve longer, which ultimately can have consequences on eventual track. Essentially, shear vs steering flow isn't enough to kill Philippe, but is keeping it weak enough to let other steering features or synoptic players have more time to develop, which, in turn, could change the eventual track. I should also add that modeling has been poor. But that isn't surprising given the more chaotic nature of what evolved between the two TCs and steering currents. All of the above made the official NHC forecast take a right beating. It is hard to be critical about that given the nature of how the pattern and systems evolved.
  15. TS Philippe, a storm I never thought had a chance to affect the Lesser Antilles, is doing that and more. Persistent convection is remaining nearly stationary in the SE quadrant of the cyclone as strong low-level convergence lifts rapidly, feeding into robust westerly mid-level flow. Significant flooding may occur into Wednesday for the islands with this setup. As for track, due to Philippe's motion WNW, the door is opening for a more W. Atlantic track. It should still turn north but may combine into a large ET cyclone that could even affect maritime Canada.
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