How Large Was Tropical Storm Isaac As He Passed By South Flo

[artist]

Does anyone know how large across Tropical Storm Isaac was as he passed south Florida? This is a really important question. Or maybe a better question is from its center to either side. Thanks in advance.

[tolakram]

You might be able to determine the size by looking at the archived images.

http://www.nhc.noaa.gov/archive/2012/IS ... hics.shtml

Surface windfield image

[vbhoutex]

Do you mean the wind field or the cloud mass? Two totally different ideas there. Still both might be available in the archives.

[wxman57]

Does anyone know how large across Tropical Storm Isaac was as he passed south Florida? This is a really important question. Or maybe a better question is from its center to either side. Thanks in advance.

Isaac was a little larger than average as far as the extent of its tropical storm force wind field. On average, TS winds will extend out about 125-130nm. Isaac's extended out to 180nm north and east of the center. That's in the top 30% of all named storms from 1988-present.

[artist]

thank you all! And yes, actually the cloud mass as well.
I will see if I can find the archived images.

[artist]

Does anyone know how large across Tropical Storm Isaac was as he passed south Florida? This is a really important question. Or maybe a better question is from its center to either side. Thanks in advance.

Isaac was a little larger than average as far as the extent of its tropical storm force wind field. On average, TS winds will extend out about 125-130nm. Isaac's extended out to 180nm north and east of the center. That's in the top 30% of all named storms from 1988-present.

wxman, thanks. And, if I recall correctly, some of the major rainbands extended even further than that?

[tolakram]

I saved a bunch of radar loops artist, and they should still be viewable in the archived threads. I try to save an annoying amount of pictures for research purposes.

This page has one: viewtopic.php?f=54&t=113366&st=0&sk=t&sd=a&start=5000

Here is one of the archived sat pics



this page has more: viewtopic.php?f=54&t=113366&st=0&sk=t&sd=a&start=4880

[wxman57]

wxman, thanks. And, if I recall correctly, some of the major rainbands extended even further than that?

Of course, rain bands in tropical cyclones typically extend WELL beyond the sustained tropical storm force winds.

[artist]

thank you tolakram and wxman for this latest info.

As some may know, our area was flooded from Isaac. And according to some that should have known and whose response we relied on, our being outside the cone...

I think you can gather from that what I am alluding to.

I just want as much fact behind me as possible.

[vbhoutex]

wxman, thanks. And, if I recall correctly, some of the major rainbands extended even further than that?

Of course, rain bands in tropical cyclones typically extend WELL beyond the sustained tropical storm force winds.

This gives rise to a question from me. How is it determined that a "rainband" is part of a TC? The reason I ask is because with Issac as with some others there appeared to be some "rainbands" that were detached and split away from the outer fringes that produced some very heavy rains for parts of FL even when Issac was near landfall. The particular one I am thinking of was over NE FL and iirc moved off to the NE.

[Sanibel]

The US got lucky because climatology probably says most storms that take that track would have been big trouble at that time of the year.

[MiamiensisWx]

The US got lucky because climatology probably says most storms that take that track would have been big trouble at that time of the year.

I respectfully but wholeheartedly disagree. The tremendous 24-hour flooding (officially 15 inches of rain but radar-indicated over 20 inches) in the western suburbs and urban areas of Palm Beach County was the most unappreciated repercussion of Isaac, but it was arguably the largest flooding event in South Florida, even within part of a single county, since Irene 1999--which produced over 18 inches at Boynton Beach--and Gordon 1994 and Dennis 1981 before then. I know that this is the case...because I have read numerous resources and official NOAA sources on this subject...and I also have personal experience on my side. Isaac was clearly the most significant rainfall event in South Florida over the past 13 years...and one of the worst since the flooding produced by the 1947 rainy season and hurricanes. Some areas in Wellington and Loxahatchee were actually still flooded a little more than a week ago...showing just how severely Isaac overwhelmed the drainage system in the historic Everglades...an area that was much less populated only 35+ years ago.

Further, while it was by no means Katrina 2005 (who even expected it to be?)...Isaac was a significant test to Greater New Orleans and produced widespread wind damage and very serious flooding...more than eight feet deep...that breached levees in sections of Plaquemines and Saint Bernard Parishes. At least tens...if not hundreds...of structures received interior flood damage...meaning hundreds of structures or furnishings, food, etc. irredeemably gutted or spoiled by floods...meaning more strain on the federal emergency budget and more misery in a vulnerable land. The wind damage in many areas was also close to that done by Katrina and Wilma of 2005 in South Florida...due to the very large wind field...i.e., the extent of sustained TS- and hurricane-force winds...of the very slow-moving Hurricane Isaac in Louisiana.

So Isaac really should not be minimized in light of what-if scenarios.

(I was in North Broward County in an area that received a foot of rain during Gordon 1994...then only a tropical storm in FL...days after it killed 1,000+ in Haiti while still a torrential TS. So I know how severe flooding is...and do not just take it from me: ask people who experienced Isaac in Greater New Orleans and Plaquemines and Saint Bernard Parishes...as well as survivors of Agnes 1972, Claudette 1979, Allison 2001, Mitch 1998 in Central America, and Floyd 1999.)

[SootyTern]

Add Homestead/Redland area to your So Fla flood archives for Katrina's first landfall: 14 to 16 inches of rain in less than 12 hours. Floodwaters into homes and businesses downtown on Krome Ave, in many residential areas, and in farm and nursery fields but the water did drain off a lot more quickly than the flooding from Isaac in PBC.