ATL: HELENE - Post-Tropical - Discussion

[chaser1]

Official forecast from NWS Tampa Bay:

Put up a weather station last week at the house my sons got me as a birthday gift. It had been pretty boring with no weather of significance since, but that's coming to an end. Will probably have to take it down at the last minute before things get too bad.

Mine has been up for 3 years now, it handles TSs pretty well

Mine is a small one screwed onto a wooden fence, it's not on a pole. It'll be toast if winds starting getting up in the 50s and beyond.

I would think you'd be able to pick up a not-so-massive post from Home Dept and drive it into the ground perhaps with a heavy rubber mallet or hammer. Unlike in S. Florida with all its Coral rock where it's damn near impossible to dig down inches without dynamite LOL. Theoretically you might then reinforce your wood fence in the process?

[Travorum]

Recon seems to have found a center relocation in the convection 1007mb as opposed to the center they found earlier which wasn’t below 1008mb. This could be the beginning of real organization

not seeing an LLC relocation per recon, seems to be in the same general area it was before.

Thunderstorms have pressure drops on their own, pretty common to see these thunderstorms have lower pressure than the center when storms are just forming and there has been no deepening/stacking yet.

Looks like this is the case based on the latest HDOB, 1006.7mb in the area of the original LLC so it has deepened a bit since the last pass.

[cheezyWXguy]

Recon seems to have found a center relocation in the convection 1007mb as opposed to the center they found earlier which wasn’t below 1008mb. This could be the beginning of real organization

not seeing an LLC relocation per recon, seems to be in the same general area it was before.

Thunderstorms have pressure drops on their own, pretty common to see these thunderstorms have lower pressure than the center when storms are just forming and there has been no deepening/stacking yet.

Looks like this is the case based on the latest HDOB, 1006.7mb in the area of the original LLC so it has deepened a bit since the last past.

Agreed, the windfield data from recon is pretty cut and dry on where the llc is, no evidence that I see of a secondary wind shift. Still, looking at satellite it seems the llc and the convection to the east are revolving around a common point, which is probably why the idea of center relocation is being discussed. Probably means the llc and mlc will just gradually converge until they are colocated.

[Sciencerocks]

Musing around a little considering pass storms here and this looks like Wilma when it become a td 150 miles southeast of where this is at. The track in the models reminds me of michael 2018(gfs, ecmwf) and 1921(hmon, etc). One of michael or 1921 will be closes to its track and intensity wise I'd guess dollars to donuts probably closer to 1921 or maybe as weak as Wilma 2005 in the gulf if John messes with its upper level high. lol


Right now probably 110-120 knts 90 miles north of Tampa.

[kevin]

There's now a very sharp pressure drop from 1013 to 1006 mbar in roughly the same location where recon found the center in the first pass. The pressure drop seems to indicate a further consolidation of this center, which would make a relocation less likely.

[cycloneye]

For those who live in Tampa, look at this about the storm surge from Dr Jeff Masters.

 https://x.com/DrJeffMasters/status/1838270283930616073

[cheezyWXguy]

There's now a very sharp pressure drop from 1013 to 1006 mbar in roughly the same location where recon found the center in the first pass. The pressure drop seems to indicate a further consolidation of this center, which would make a relocation less likely.

I saw that too but it looks suspicious. As they approached the center, the pressure rose from around 1010 to 1013, then dropped to 1007. Looks like an error to me

[Nederlander]

There's now a very sharp pressure drop from 1013 to 1006 mbar in roughly the same location where recon found the center in the first pass. The pressure drop seems to indicate a further consolidation of this center, which would make a relocation less likely.

Agreed.. Looks like it has a better than decent shot at shooting the channel clean.

[kevin]

A very clear center at 17.7N and 82.1W with 1006.0 mbar and 10 kt winds. Supports a current intensity of 1005 mbar. So far FL winds have peaked at 45 kt and SFMR peaked at 43 kt. Blends together to a toss up between 40 and 45 kt. Due to the broadness of the system conversion factors are usually higher so I'd go with 45 kt. Together this thus results in a 1005 mbar / 45 kt TS Helene. Interested to see what NHC will do with the data in about 1 hour when the next advisory comes out.

[Jr0d]

This afternoon's east trend is obviously troublesome for Tampa Bay and even for me in Key West..it won't take much of a jog further east for the lower Keys to see widespread and long lasting tropical storm winds and significant storm surge. I did notice we are part of the state of emergency which will make it much easier for FEMA relief if there is significant damage. Monroe county never declared an emergency for Ian, despite seeing strong tropical storm conditions and many homes being flooded to and not habitable, it took us over 3 weeks before we got FEMA relief while paying out of pocket to live in a hotel because it took that long for Monroe County to be declared part of the Ian disaster zone.

Stocking up on water and non perishables now. Might make a Home Depot run tonight or early tomorrow if this trend continues.

[caneman]

Caneman, My son lives right across the intracoastal from Indian Rocks Beach. He does not seem to be concerned about surge. What are your plans?

regards,

jad

That is about where I live just on the eastern side of the intercostal. My house fortunately is about 20 feet up so I'm not worried. Everything else around me would likely be flooded though. It all depends how high above sea level is he?

Not exactly sure the exact elevation, but I am sure he knows as he is a Civil Engineer by trade.

That's the big thing. I'll ride out wind and torrential rain but will not mess with storm surge. Since he's an engineering and thinks logically, I'm sure he would know the risk of storm surge.

[wx98]

With the still somewhat elongated center, I’d say NHC will stick with PTC for another advisory cycle. Winds should come up with this update. TD/TS likely overnight.

[robbielyn]

On the current path even parts of Naples and Marco Island is looking at 3-6 feet of water. This is shaping up to be a major surge event for the entire west coast of Florida. I imagine mandatory evacuations of Zone A will have to be called for pretty much the whole west coast.

What I hate about zone A at least in hernando county, it includes all mobile homes no matter how far inland we are. Im 20miles from the coast. I wish it only included maybe those close to us 19 on the east side.

[StPeteMike]

This afternoon's east trend is obviously troublesome for Tampa Bay and even for me in Key West..it won't take much of a job further east for the lower Keys to see widespread and long lasting tropical storm winds and significant storm surge. I did notice we are part of the state of emergency which will make it much easier for FEMA relief if there is significant damage. Monroe county never declared an emergency for Ian, despite seeing strong tropical storm conditions and many homes being flooded to and not habitable, it took us over 3 weeks before we got FEMA relief while paying out of pocket to live in a hotel because it took that long for Monroe County to be declared part of the Ian disaster zone.

Stocking up on water and non perishables now. Might make a Home Depot run tonight or early tomorrow if this trend continues.

Tomorrow will be the day that the stores will be ransacked I feel like. If you don’t have supplies, water, food now; I would do it before the news start showing headlines with “major hurricane” “catastrophic damage” etc. Not saying they overhype things, you just know what get people going after seeing it for about 20 years (Charley).

[Jr0d]

A very clear center at 17.7N and 82.1W with 1006.0 mbar and 10 kt winds. Supports a current intensity of 1005 mbar. So far FL winds have peaked at 45 kt and SFMR peaked at 43 kt. Blends together to a toss up between 40 and 45 kt. Due to the broadness of the system conversion factors are usually higher so I'd go with 45 kt. Together this thus results in a 1005 mbar / 45 kt TS Helene. Interested to see what NHC will do with the data in about 1 hour when the next advisory comes out.

If the threat level was not so high, I could easily make the argument of no upgrade due to such a broad center.

However a named storm will get people's attention much faster than PTC advisories, calling this Helene at 5pm could help motivate those in vulnerable areas to start getting their plan together and supplies tonight instead of waking up surprised tomorrow(and possibly in a bit of a panic), because of this I think an upgrade is justified for public safety.

[NXStumpy_Robothing]

There's probably enough of an argument to have a 35-40kt TS Helene at 5 PM, though it's a bit borderline I suppose. Decent support from recon through the convection for a pretty east-weighted swath of TS or near-TS winds around the heaviest convection, and pressure/winds have tightened up significantly near our developing LLC.

NHC still has the final call, of course.

[wx98]

I think you are misunderstanding the NHC forecast process and trying to use it as justification for insinuating that this storm won’t get as strong as most think. The intensity forecast will only go up with time.

He's a great example of why I believe the NHC needs to change their NHC intensity forecast products. I ran into it with Michael, so many people only see that one number and say "that's the forecast!" when in reality the forecast is for a wide intensity range, most people just don't read the discussion.

And then on the flip side there are those that enjoy the sensationlized aspect of danger. It goes both ways. I err on the side of being a current realist and let the developmenting situation unfold. I am in no way stating anything profoundly wrong here. I am posting the real and simple fact it is currently expected to be a CAT2 by landfall. Nothing less nothing more. Pretty simple.

All being said. I can read and comprehend very well thank you. And to those in the projected path stay alert get ready and MOVE as soon as possible in the event this comes your way. Regardless of intensity it makes ZERO sense to stay in the path of any hurricane if you can leave to safe ground for a day or two.

The next advisory will show a Cat 3 forecast point…

[AnnularCane]

I have a bad feeling we're going to wake up to a beast tomorrow morning. For those who remember Ian in this area of the Caribbean, we went to bed with an ugly-looking storm and when we woke up in the morning, it blew up into a monster. I have a strong hunch we're in for that same scenario tonight.

I don't actually remember that, but I do remember going to bed with Opal expected to be Cat 1 or 2 at landfall, and waking up to find a strong 4. Fortunately (for me) she was going well east of me in NOLA back then, but I imagine there were more than a few palpitations in the FL panhandle that morning.

[Ubuntwo]

Looks like this recon flight has a bit of a high bias. Lowest pressure on the center pass was 1006.0mb while Grand Cayman almost two degrees to the north is reporting 1005.0mb at the moment. Extrapolation would put this around 1003 or so.

[tropicwatch]

Looks like this recon flight has a bit of a high bias. Lowest pressure on the center pass was 1006.0mb while Grand Cayman almost two degrees to the north is reporting 1005.0mb at the moment. Extrapolation would put this around 1003 or so.

Buoy42057 reporting 1004.4.