Hurricane Helene

[Thunder Snow]

Helene slightly stronger on latest update

[WeatherArc]

The sun sets on an increasingly organising Helene

Earlier today her low level circulation was exposed, however with windshear fast beginning to fade on her western quadrant, its likely she will finally be able to blow up more towers on the western side and form a more compact center, she will also likely attempt to couple her low and mid level circulations, once Helene has completed this she will be able to freely intensify, the question is what/how much will she be able to do tonight.

 

A buoy just off the coast of the Yucatan has recorded a large drop of pressure inside Helene, down from 1004mb to 999mb, likely another sign shes beginning to get her act together.

Personally, im of the belief below that Helene will not make landfall (or receive only a glancing blow) from the Yucatan peninsular.

Edit-Pressure now down to 992mb, drop of 1mb per 10 mins. Helene really going for it tonight.

Edited September 24 by WeatherArc

[WeatherArc]

Given the data coming in tonight im fairly sure Helene has now entered a period of rapid intensification, pressure now down to 990mb. She could well be a hurricane in 12 hours. She has also begun a more northerly track instead of her earlier westerly one.

Shes currently outpacing all the models on her intensity, barring landfall on the Yucatan Helene will have pristine conditions to continue this rapid intensification into a Major Hurricane by Thursday night.

 

[Jo Farrow]

The Mexican met service, as Helene brushes past today. https://smn.conagua.gob.mx/es/

 

Florida prepares for the threat of Hurricane Helene

WWW.NETWEATHER.TV

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Cyclones John and Helene bring torrential rain and high winds this week. Hurricane John hit western Mexico and Helene is forecast to strike Florida as a major hurricane on Thursday.

 

[Jo Farrow]

From a pal in Orlando

[matty40s]

 

[karyo]

The NHC 4am update is out. Helene is continuing to strengthen!

Maximum  sustained winds 65mph

minimum central pressure 985mb

It looks like Helene will scrape the northeast Yucatan in the next few hours before entering the GOM.

[Alderc 2.0]

Looks like any dry air has been ingested and dealt with. Looking at the imagery the centre of the circulation looks like staying just offshore from Cancun so Helene should have a full green light to strength. Only thing preventing a massive ramp up is the shear size of the storm, sometimes takes a bit longer to consolidate the core and then if there are any potential ERC’s other I would have side a high end cat4 or cat5 would have been likely. 

[karyo]

The 7am NHC update shows that Helene has strengthened more and nearing hurricane strength!

Maximum  sustained winds 70mph

Minimum central pressure 979mb

The pressure drop is particularly noteworthy

[FetchCB]

Cuban Radar image

[Thunder Snow]

Helene is now a hurricane 80mph 

[WeatherArc]

Yup, there we go Helene is now a Hurricane, NHC considering upping the landfall forecast from a high-end Cat 3 to a Cat 4.

 

[mountain shadow]

Plenty of time to make Cat 5

[WeatherArc]

 mountain shadow Honestly Helene could make the Cat 5 run imo. Dependent on light shear and less dry air though. However, over the next day or two she will enter the Gulf and some very favorable conditions, perfect outflow helping her vent and rapidly draw air up from extremely high oceanic heat content values. The only thing that could potentially hinder Cat 4/5 development is an Eye Wall Replacement Cycle.

 

Helene looking pretty amazing this afternoon (note the drier air being wrapped anti-clockwise to her south and east, unlikely to affect her much) 

[matty40s]

Bit wet in Cancun..

Evacuations have started...

 

[WeatherArc]

HAFS-A wants Helene as an 162mph Cat 5 with pressure at 923mb, forecasts that rapid intensification will start in around 12-15 hours.

Edited September 25 by WeatherArc

[Thunder Snow]

 WeatherArc wow scary 

[WeatherArc]

Cuban radar showing that Helene is really trying to get an eye formed now just off the coast of the Yucatán peninsular

[WYorksWeather]

The NHC have issued the latest update. Helene is now set to an initial intensity of 75kt / 85mph - now a mid-tier Cat 1.

The big news is that intensity is expected to reach 115kt / 130mph in 24 hours, and further strengthening is possible beyond that before landfall. Even 115kt would put Helene into Cat 4.

Quote

The environment appears primed for significant strengthening while Helene moves across the Gulf of Mexico. The forecast track more or less runs along the axis of the Loop Current during the next 24 hours, where ocean temperatures are about 30 degrees Celsius. In addition, Helene will be moving through an environment of low vertical shear and strong upper-level divergence. Some of the Rapid Intensification (RI) indices, particular DTOPS, respond to this environment by indicating at least a 90 percent chance of a 35-kt increase in intensity over the next 24 hours. The NHC intensity forecast now shows an intensity of 115 kt (Category 4) at 24 hours, which is mirrored by several of the regional hurricane models and the SHIPS guidance. It should be noted that additional strengthening is possible beyond 24 hours before Helene makes landfall Thursday evening.

 

Hurricane Helene Forecast Discussion

WWW.NHC.NOAA.GOV

 

[mountain shadow]

Now forecast to be Cat 4 at landfall.

Edit. WYorks weather beat me to it.

[matty40s]

 

[WeatherArc]

Im unfortunately getting more and more confident that Helene will be a catastrophic event when she makes landfall, the NHC has not only upped her intensity to a Cat 4 as mentioned above but has also upgraded the predicted storm surge to 20 feet or 6 meters! No sugarcoating it, if this level of surge materialised it will be catastrophic. Residents need to evacuate right now.

 

Edited September 25 by WeatherArc

[Thunder Snow]

There is every chance she could make a cat 5, going to have high impacts in its path unfortunately 

[WeatherArc]

As the sun sets over Helene it looks like she's attempting to form an eye, 

If you look closely enough on the IR gif above (ive circled the exact area below) you can see a convective hot tower fire and immediately begin to rotate counterclockwise, this is likely the beginnings of a proper eyewall formation, i would expect to see more convective towers fire around her eye, if we see any very hot towers fire near the eye we'll know she's entered rapid intensification.

[WeatherArc]

Imo the one saving grace that could stop Helene going ballistic is the drier air shes ingested, its helped stall things today.

However all eyes are on tomorrows Diurnal max, its the most favorable time for her to significantly intensify.

Continuation of my earlier post above this one, a second hot tower has fired and has begun to rotate anti-clockwise around Helene's eye, furthering my belief shes attempting to form an eyewall.

 

Edit-The latest hurricane hunters flight confirmed Helene's eyewall is closed, with the exception of a little bit of dry air remaining outside the eyewall it looks like green lights for Helene to begin rapid intensification.

Edited September 26 by WeatherArc