ATL: IAN - Post-Tropical - Discussion

[Jag95]

Anyone has the closeup view of trayectory with the line?

I just zoom in on the NHC interactive cone and make sure to have "track" checked. Now showing landfall just north of Venice.

https://www.nhc.noaa.gov/refresh/graphi ... k#contents

I just zoomed in on the track and saw Port Charlotte a little to the south. Getting pretty close to Charley-land.

[Category6]

Hasn't stopped raining here in Plantation (just west of Fort Laud) for the last 12-15 hours. Some light to moderate pockets mixed in with heavier bands. Looks like we've received about 4 inches of rain already. No wind at all so far.

[USTropics]

Unless I'm mistaken, Wxman57 discussed the shear that will affect Ian, and weaken it somewhat upon its approach to land...this is an excerpt from the 5am NHC discussion..."By 24
to 36 hours, increasing southwesterly vertical wind shear and drier
mid-level air are likely to result in some gradual weakening." By favorable wind shear, do you mean favorable because it will weaken Ian somewhat?....Just to be clear Ice, thanks!

The direction of the wind shear is currently favorable for more intensification because the storm is moving in the same direction as the shear, but the direction will eventually change in the next 48-72 hours to unfavorable direction combined with dry air behind this cold front.

I've been wondering about this too.

I know the placement of the front and its steering currents were major considerations when we were trying to figure all this out. Now, we've not heard anymore about where the front is, where it's going to be, and how much it will continue to "steer" the storm.

In regards to the shear, the difference is the flow between the lower-levels and upper-levels. Here is the GFS forecast for 24 hours showing 850mb heights with wind barbs. We have our trough located towards the north but behind it we have building high pressure (outlined in yellow). This creates a sharp gradient with flow roughly highlighted in purple:


For an even better illustration of this, we can use GFS data forecast here (https://earth.nullschool.net/) to create a more "fluid" representation. Here is an image 24 hours out of the low-level flow:


Now let's go look at the flow in the upper-levels of the atmosphere (200mb), outlined in purple:


Here we can see the flow is out of the SW towards the NE, which is the complete opposite of the flow we have at 850mb (low-levels). This is the quintessential definition of shear (flow in opposite directions at different levels of the atmosphere). Again, here is the flow on earthnull:


We can see that while shear will increase as Ian continues past 25N, a more eastern or southern track (as we're seeing today) would not be nearly as detrimental and only likely tamper off strengthening as the system approaches the coast. If you take a look at Euro soundings, shear to the north is in excess of 50-60 knots but only ~10-15 knots over Ian.

[SouthFLTropics]

I've always been interested in what role the frictional effects of land have on the motion of a developed storm. We've seen numerous times where a storm center would dance around a land mass. Ivan going around Jamaica was one of the most memorable. I'm wondering how much, if any, frictional effect that the peninsula may be having on the direction of Ian? I'd be interested to see if there has been a study done on this topic.

[Rail Dawg]

Guys I chased 16 hurricanes and ‘retired” after Hurricane Michael.

I used to be almost all alone doing it but with social media the dynamics changed. Lots and lots of chasers now.

185mph gusts in Michael with Fists of God punching down 300-year-old oak trees. Houses flying away.

It was a good run over the years. So many good people here on storm2k… Couldn’t have done it without all ya’lls help.

Chuck

[ScottNAtlanta]

I would say this is in a great location to significantly intensify. It is at the perfect angle/distance from the trough to ventilate and it will be traveling over 30/31 degree waters right up to landfall. This isn't going to get far enough north for shear to weaken it.

[eastcoastFL]

When you look at the NHC line on the SFWMD radar the shift east at 11am seems more pronounced


https://apps.sfwmd.gov/sfwmd/common/images/weather/noaaport/radar_flanim.gif

I wonder what the rainfall estimates per hour are, as seen in the heavier bands, shown on this radar loop?

On the SFWMD website they have “raindar” estimates page

[tolakram]

[ScottNAtlanta]

Guys I chased 16 hurricanes and ‘retired” after Hurricane Michael.

I used to be almost all alone doing it but with social media the dynamics changed. Lots and lots of chasers now.

185mph gusts in Michael with Fists of God punching down 300-year-old oak trees. Houses flying away.

It was a good run over the years. So many good people here on storm2k… Couldn’t have done it without all ya’lls help.

Chuck

I would call that going out at the peak of a chasing career.

[eastcoastFL]

I've always been interested in what role the frictional effects of land have on the motion of a developed storm. We've seen numerous times where a storm center would dance around a land mass. Ivan going around Jamaica was one of the most memorable. I'm wondering how much, if any, frictional effect that the peninsula may be having on the direction of Ian? I'd be interested to see if there has been a study done on this topic.

Laura was pretty interesting in that respect. You had the euro constantly killing her off or failing to develop her and she continued to develop as she crossed each island.

[Iceresistance]

Lots of lightning in the Northern Eyewall, he's ready to RI again.

[eastcoastFL]

https://i.imgur.com/RkKaB9l.gif

Not a whole lot to say about that other than Wow. What a magnificent storm to watch.

[underthwx]

https://www.nhc.noaa.gov/storm_graphics/AT09/refresh/AL092022_3day_cone_with_line_and_wind+png/100939_3day_cone_with_line_and_wind.png

With a core that big, which will likely expand upon landfall, there’s little doubt that even if landfall is south of Tampa, that the city could unfortunately experience high winds and rain. This is not Charley 2.0. It’s much bigger.

Tampa bay area survived Irma and Ian may not be much worse for Tampa bay depending on the evolution of the track. All the shear is further NW so probably not the best outcome imaginable.

The 11 am NHC update stresses the fact, that significant wind, storm surge, and rainfall hazards will extend far from the center of Ian...those hazards, coupled with a "very uncertain track", warrant a heightened sense of awareness, and appropriate action taken now, to protect yourselves...given the proximity of this cyclone to the warned areas, do now, what you need to do, before conditions deteriorate...

[ScottNAtlanta]

I've always been interested in what role the frictional effects of land have on the motion of a developed storm. We've seen numerous times where a storm center would dance around a land mass. Ivan going around Jamaica was one of the most memorable. I'm wondering how much, if any, frictional effect that the peninsula may be having on the direction of Ian? I'd be interested to see if there has been a study done on this topic.

Laura was pretty interesting in that respect. You had the euro constantly killing her off or failing to develop her and she continued to develop as she crossed each island.

If you look at this loop you can see how Ian hugged the coast before going back out

https://weather.cod.edu/satrad/?parms=m ... =undefined

[TheHurricaneGod]

Clearing out nicely.

[Jr0d]

Anyone has the closeup view of trayectory with the line?

https://i.imgur.com/fyvdsyC.png

For those of us in tampa,st pete, and like me in land o lakes, this track is so much better. Hopefully my now complacency today doesn't end up biting me

This shift is not looking good for Key West. I think we will be seeing close to hurricane force winds, perhaps a little more.

Given the track shift, Im surprised we do not have a hurricane warning. The surge will likely be higher than Irma for Key West. Many forget we were on the weak side of Irma, with minimal hurricane conditions and not much surge(while 30 miles east got battered).

Considering the surge as well, Key West may have worse conditions than Irma while being grossly under prepared.

My location bias is certainly plays a role in my concern, but I dont like what im seeing

[eastcoastFL]

https://i.imgur.com/fyvdsyC.png

For those of us in tampa,st pete, and like me in land o lakes, this track is so much better. Hopefully my now complacency today doesn't end up biting me

This shift is not looking good for Key West. I think we will be seeing close to hurricane force winds, perhaps a little more.

Given the track shift, Im surprised we do not have a hurricane warning. The surge will likely be higher than Irma for Key West. Many forget we were on the weak side of Irma, with minimal hurricane conditions and not much surge(while 30 miles east got battered).

Considering the surge as well, Key West may have worse conditions than Irma while being grossly under prepared.

My location bias is certainly plays a role in my concern, but I dont like what im seeing

How’s the weather been so far ?

[wxman57]

Once again, NHC track moved right on top of mine. With SW-W sheared storms in the Gulf, they almost always move more quickly and turn sharper east than predicted. I have it inland in the Sarasota-Venice area around sunset tomorrow (always at night). Could be south of Venice. The farther south it tracks, the stronger it will remain up to landfall. SLOSH indicates 12-14 ft where the center meets the coast. Wouldn't be anything into Tampa Bay.

[psyclone]

I'm definitely still concerned about the northwest side rain bomb that may develop...but if the cyclone keeps ticking east that will end up east of here too.

[tolakram]

With a core that big, which will likely expand upon landfall, there’s little doubt that even if landfall is south of Tampa, that the city could unfortunately experience high winds and rain. This is not Charley 2.0. It’s much bigger.

Tampa bay area survived Irma and Ian may not be much worse for Tampa bay depending on the evolution of the track. All the shear is further NW so probably not the best outcome imaginable.

The 11 am NHC update stresses the fact, that significant wind, storm surge, and rainfall hazards will extend far from the center of Ian...those hazards, coupled with a "very uncertain track", warrant a heightened sense of awareness, and appropriate action taken now, to protect yourselves...given the proximity of this cyclone to the warned areas, do now, what you need to do, before conditions deteriorate...

As sanibel stated earlier, he's treating it like a direct hit with hours and hours of bad conditions and is bugging out. People either treat these storms with respect or let luck decide their fate. We will know landfall location at the point of landfall.