FL Backdoor hurricane question

[Anonymous]

I've wonderred could there ever be a situation where there was a hurricane coming from the Gulf crossing fla into the Atlantic (or vice versa) and it stay strong enough for the east coast coastal residents to need to evac? I know hurricane warnings would be issued and flood prone areas and mobile home reidents would have to leave but not sure if storm surge would still be a problem for the opposite coast. Local news usually says here if a storm is in the gulf that its just a heavy rain event and "its on the wrong side". But this graphic says if a cat IV storm was moving at 16kts, it would be a problem. Not sure if thats possible though cuz when storms start moving N or NE at that speed, they usually are weakenning due to influences from a front... Andrew was a good example though...Did west coasteners have to leave with him?

[Derek Ortt]

Surge would not be a problem for the EC s the surge heights are the lowest for the mianland even for a cat 5 landfall on the EC (andrew only produced 16.9 feet, about that of what Opal, 2 cats lower produced on the Panhandle). There would be some problem for the GC though on a cross over. Andrew did cause a 7.9 foot surge at Flamingo, which I believe, would be much higher if Tampa took a "backdoor" direct hit due to the Bay and the shallower water

[vbhoutex]

The actual surge the East coast on a West to East run would not be as much of a problem as it would not be moving across water for any length of time being pushed by the wind. There would definitely be some surge but not like on the West coast as it came in. 2 Differences-the first I addressed above. The second is the West coast has a shallow shelf that extends miles out into the GOM that the surge would be building up on also. That shallow shelf is not so prominent on the East coast. That is not to say that storm surge would not happen on the East coast. Just look at Andrew.

What surge there would be on the West coast during an East to West passage would be to the South of the centers passage and even though it would be enhanced by the shallow shelf mentioned above it would be minimal due to once again lack of time to build up.

On an West to East passage the surge on the East coast would be to the North of the center and minimal for reasons above.

[Anonymous]

OK and surge is usually the only reason coastal residents have to leave correct? Unless they in a mobile home or flood area.

[HURAKAN]

It is possible, you just need a major hurricane to see your wonderred situation to happen.

[MWatkins]

Surge wouldn't be as much of a direct problem as would inland and coastal flooding.

Like in the case of Irene...the easterly flow on the right side of the storm causes ocean water to get pushed back inland. This tends to block the canals heavily relied upon for drainage...and the rainwater backs up.

Slow moving systems...like Cleo of '64...could cause 50 or 100 year flooding events.

MW

[vbhoutex]

OK and surge is usually the only reason coastal residents have to leave correct? Unless they in a mobile home or flood area.

It is the only reason coastal residents would be ordered to leave. Wind damage possibilities are not used to determing evacuations. As we all know the damage in S Florida from Andrew was indiscriminate whether you lived in a mobile home or not, but there are no decisions to order evacuations that I know of based on anything other than flooding and storm surge. I don't believe people can even be ordered out of their mobile home unless it is a flooding concern. Heck, in Texas we don't even have mandatory evacuations!!! However, they will go door to door when it is a bad situation and ask for a list of your next of kin.

[Derek Ortt]

Mobile home areas have been ordered for evacuation purposes before in major cane events, due to their vulnerability.

Here in South Miami, even though I am about 5 miles from the coast, I am in a mandatory evac zone (zone 2, I believe), meaning I am "required" to leave for all major hurricanes. However, I wont be doing so and in fact, may be in my office, if necessary, during any cane event

[Guest]

Jekyhe, you need to read about the September 29, 1896 storm that affected North Florida. It came ashore as a cat 4 at Cedar Key. If this storm was on a more direct path for the Jacksonville area, then there would be a storm surge sufficent to call for evacs of the east coast. This storms eye crossed over Lake City, and pretty much destroyed all of inland North Florida..
There are two places in the United States that have the potential for the worst storm surge. First is Southeast Louisiana, second is the Northeast Coast of Florida, and Southeastern Coast of Georgia.
Why, Northeast Florida? Because of the curvature of the coast. This of course would have to be a cat 4-5 hurricane, which one accured ion October 2, 1898. This storm hit Cumberland Island on a due west track. It left a pilot boat on a 20 foot bluff at High Point, Ga. The storm had a 16 foot storm surge in Brunswick, Ga. Plus, based on records from diaries and old newspapers, plus some additional investigation in the Okeefenokee Swamp, that the storm surge traveled inland to the swamp via the St. Mary's River. This caused massive flooding to all of Southeastern Georgia and Northeastern Florida. This particular storm is compared to Hurricane Hugo in 1989.
So what I'm trying to say, is it doesn't matter where the storm comes from, the Gulf of Mexico or the Atlantic. What does matter is the size, strength, aforward speed, and the exact track of the storm.
Best bet would be, if a storm of cat 4 or 5 was on a track to cross North Florida, and that track to go over Jacksonville, I would be conserned of a storm surge, especially because of the erosion we have seen the past 10 years along the coast.

[Brent]

Surge wouldn't be an issue, but a hurricane would DEFINTELY not lose a whole lot of strength crossing Florida, especially if it moves quickly(15 mph or so).

[Derek Ortt]

Brent, a cane would weaken at least 3 categories while crossing Florida. Even Andrew weakened from 145KT to 110KT, and it was only onshore for 4 hours. Most storms take 8-12 hours to cross Florida; thus, they would lose about 30-50% of their wind speed that they had while making landfall

[Brent]

Brent, a cane would weaken at least 3 categories while crossing Florida. Even Andrew weakened from 145KT to 110KT, and it was only onshore for 4 hours. Most storms take 8-12 hours to cross Florida; thus, they would lose about 30-50% of their wind speed that they had while making landfall

WHOA. I didn't think that would happen. Florida is very flat.

[King6]

Florida may be flat,but it's still Land:) Glad Andrew was an overnight storm,Imagine a storm traveling 7mph,taking a day in a half,would be terible.

[Anonymous]

Well, this weekend, I may get my question answered by mother nature herself *IF* the NHC is correct

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OUTLOOK VALID 15/0000Z 31.0N  82.0W...INLAND
MAX WIND  65 KT...GUSTS  80 KT.


[bahamaswx]

Don't expect much.

[soonertwister]

A storm passing over south Florida may retain much of its strength due to the large amounts of wetlands and no geographical obstruction, especially if it is moving fairly quickly and is a large storm.

Nobody can convince me that anyplace could be worse than Collier County, Florida (Naples) when it comes to storm surge danger. According to what I read from the NHC, almost the entire populated area of the county would be inundated in the event of a category 4-5 hurricane that either made a direct hit, or headed up the Florida west coast immediately offshore. Not only would those at risk be afloat in a hurricane, they very possibly would be washed out to sea.

<img src="http://www.collierem.org/sloshweb.gif">

[PTPatrick]

not to say Collier doesnt have issues BUT...if you look at other counties you will see that A: they all have low topography, and are very vulderable to storm surge(even more so between Apilachicola and Tampa) and B, the vast majority of them all have the populations concentrated very near the coast. In other words, most of the counties on West Florida would be in the same boat...Try evacuating ALL of Pinellas county. All I can say is if a cat 4+ ever goes in there I would NOT what to be on the civil defense team. Fasten ya seatbelts, its going to be a bumpy night.

[Steve H.]

REmember also this storm will be moving rapidly. Won't lose that much steam.

[Aimless]

My thoughts/concerns ...assuming Charley follows the current track, enters Flordia somewhere in the vicinity of Tampa as a strong 1 or Cat2, and crosses Fl NE, at the current speed ( it is moving fairly fast):

It probably would not gain strength as it crosses Florida, but wouldn't lose much either. It would dump more water on already saturated areas - so flooding is a problem everywhere along its track ( hoping for continued speed in that respect). But, as it exits Florida and into the Atlantic ...perhaps around Jacksonville, wouldn't it have the potential to begin gaining strength again and wouldn't points north of the exit point ( and some south) then have surge potential?

[Anonymous]

This Jacksonville/Duval Co forecast is enough to cause damage and power outages to an area not used to such storms.

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Friday. Mostly cloudy. A chance of showers and thunderstorms then showers and thunderstorms likely in the afternoon. Becoming very windy. Highs in the upper 80s. Shifting winds 30 to 40 mph with gusts to 50 mph possible. Chance of rain 60 percent.