Windspeed

Felicia at 18z on Tuesday per HWRF. I suspect it will weaken even faster than the HWRF is modeling due to very dry stable airmass being advected into the core with the increasing southwesterly VWS.

Felicia indeed still looks impressive. Some WSW VWS should begin increasing over the next 24-36 hrs. This combined with a subtle decrease in thermodynamic support should bring on a gradual weakening into abrupt faster weakening into Tuesday. The HWRF shows a period of rapid weakening on Tuesday as the MLC gets decoupled.

No. There is certainly nothing official with regards to forecast discussion or analysis that suggests this is a Category 5. TAFB Dvorak analysis hit T6.5/127 kts per discussion and ADT numbers are about 10 kts lower. Felicia has already maxed out for an annular-type TC within the current thermodynamic environment. It would need to drop a bit more latitude and reach warmer SSTs to get any stronger. Even with cooler upper tropospheric temperatures, Felicia's core is riding a 26.5 to 27°C isotherm. Its eyewall has probably maxed out potential intensity at its current westward vector of motion.

1) Nowhere will you ever find data to support classification or naming of an ULL. The sarcasm here is noted, but out of bounds. As far as areas of interest, there are plenty of examples of mid-level systems and cold core upper troughs transitioning to warm core systems. But that is for another discussion. 2) Satellite technology and ever increasing shipping traffic now enable us to recognize and discern warm core and assymetric warm core cyclones that warrant more subtropical classifications than in years past. There is no agenda here except to supercede and fulfill a critical obligation by the TAFB division of the National OCEANIC and Atmospheric Agency. That role is to protect life and property for maritime shipping interests, not just the inhabitants of coastlines. If a system meets the criteria, it gets classified. This is a scientific agency, there are rules, but technology and subsequently guidlines evolve over time. 3) Going to nip this in the bud right here. Any more talk of an agency misleading or lying to fit a political agenda, much less climate change, will be removed. This is not the thread for such discussion.

lol..

A symmetrical doughnut...

Ooof..

Already at the "F" named storm and we didn't even make a thread. We have not seen anything crazy at this point, but it's not exactly been quiet either. Felicia is intensifying and expected to become a hurricane by tomorrow. No threat to land. I am sure someone will want to post "bye" when it dissipates over cooler surface waters next week.

There's a good discussion ongoing about 2021 following suite with 2020, '18, '16, that late September through October will experience peak activity versus a traditional climo-favored late August to mid September peak. This would not surprise me in the least. Especially if there is robust MDR warming in September versus typical late July-August and heft poleward motion of the ITCZ. A slightly below average MDR SST anomaly is currently in place. That may be the only other negative factor against early CV August activity beyond PVs and SAL. Though we are still weeks away and slightly below mean SST data sets can reverse pretty quickly given a few weeks of decreased low level easterlies.

With a -ENSO in place, an active August may hinge upon whether the EPAC enters a suppressed regime while a strong WAM continues in the EATL. If PV anomalies are somewhat in check across the Atlantic Basin, then CV season likely kicks off early. Current Bermuda High placement is already a potential harbinger of Caribbean Cruisers. Any subtropical development could threaten Florida, but any deep MDR development likely would maintain Caribbean potential. I expect more Caribbean hurricanes this season. Weak PV anomalies and a suppressed EPAC would obviously increase their ACE potential by mitigating VWS. To further add upon this, note these graphics by Ben Noll: Keep in mind that sinking air is only prohibitive of TC development in the genesis stage. With modeled subsidence in August across the EPAC, this may squash TCG occurring there and subsequently qualm outflow induced VWS across the Caribbean and Antilles into the Subtropical Atlantic. Likewise, with atmospheric instability / lift in the EATL coinciding a +WAM, TCGs will be supported from frequent healthy tropical disturbances rolling off the African Continent. Granted, limiting factors such as strong PVs and SAL can still work against potential TCs crossing the MDR, but if those factors are limited, a TC will have no issues intensifying into the WATL. Timing of occasional favorable CCKWs enhance these regardless of overall airmass regime. At least at this point, an active August looks possible, and certainly a hyperactive September is in the cards as well.

[emoji102]

You joke but... In all seriousness, a cool upper level low can allow for some pretty intense lapse rates and thunderstorms this time of year over the hot coffee thermos that is Florida.

Convective organization consolidated into an eyewall is usually seen and needed to sustain the vortex of the tropical cyclone at ≥74. But that isn't always the case. We have seen eyewalls form in core convention in moderate tropical storms that were only producing 50-55mph winds. Likewise we have examples of hurricanes with broken cells around the vortex that were not producing a solid or even semicircle eyewall. Again, it is not merely the appearance and structure that classifies a hurricane; in situ wind data (or satellite derived estimates, if that is only available) and a closed warm core surface vortex are the requirements for TC classifications.

^This too.

Elsa had stronger surface-based convergence and trade winds on the northern semicircle of its closed circulation than Andrew had in its initial intensification phase. Background in situ tropospheric conditions are just as important as the surface vortex barometric forcing in a tropical cyclone for surface winds. Not all TCs evolve the same. Environment matters as do wind obs.

The classification has never changed. ≥74MPH sustained surface winds in a tropical cyclone is classified as a hurricane/typhoon depending on basin.

Rare that it survived the Caribbean as a classified tropical storm this time of year. Rare it reached hurricane intensity more than once while surviving land interaction this time of year. It's also worth reiterating how damn crazy Hurricane Dennis was in 2005, which reached Cat 4 intensity in the Caribbean and made landfall as a Category 3 in the Florida Panhandle sixteen years ago today.

Look out, Jacksonville...

Yikes...

Charley was already well-organized and made landfall as a hurricane in Cuba. Elsa, though convectively active, is still yet to put itself in a position to intensify rapidly. Now could that occur? Sure. But it needs to be developed to really take advantage of diffluence. Otherwise, it's high end TS to minimal hurricane at best. I don't think this will be a Charley. Too much against it.

Center/LLC relocations are allowing Elsa to thread the needle, but at the same time, such reorganization can take time to respond with pressure falls and intensification. Despite the present more symmetrical convective envelope, banding and a healthy MCS, Elsa needs to chill with the break down and reformation of low-level vorticity maximums before it's going to experience a prolonged period of reintensification.

Yeah I think they just missed earlier due to fast rate of motion and small low-level vortmax.

Convection is trying to wrap upshear around the LLC. The mid-to-upper easterly flow might be starting to amplify now. We'll see if that can counter the high speed low level flow somewhat for less of a deep layer tilt to the vortex. May still remain somewhat weak regardless.