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Ok this about 1960 and there was apperently a cat 5 that nearly made landfall in new orleans at that strength, But here is what boggles me the nhc prelim sais recon reported 140knt winds and a pressure of 972 millibars? I am assuming thats not at the surface but even so it calculates to 125 knts 145mph with that pressure? Prelimanry report |
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Robert, I was actually referring to Donna from 1960, but Ethel indeed reached CATV status for a very short period of time. Fortunately she landfalled as "only" a CAT I. Date: 14-17 SEP 1960 Hurricane ETHEL ADV LAT LON TIME WIND PR STAT 1 23.90 -90.60 09/14/12Z 40 - TROPICAL STORM 2 25.60 -89.70 09/14/18Z 75 - HURRICANE-1 3 27.00 -89.10 09/15/00Z 110 981 HURRICANE-3 4 28.10 -88.90 09/15/06Z 140 - HURRICANE-5 5 29.10 -88.90 09/15/12Z 80 - HURRICANE-1 6 29.90 -89.00 09/15/18Z 60 - TROPICAL STORM 7 30.70 -89.00 09/16/00Z 45 - TROPICAL STORM 8 31.30 -89.00 09/16/06Z 35 - TROPICAL STORM 9 32.00 -88.90 09/16/12Z 35 - TROPICAL STORM 10 32.90 -88.50 09/16/18Z 30 - TROPICAL DEPRESSION 11 33.90 -88.10 09/17/00Z 25 - TROPICAL DEPRESSION 12 35.00 -88.00 09/17/06Z 20 - TROPICAL DEPRESSION 13 36.00 -87.60 09/17/12Z 15 - TROPICAL DEPRESSION 14 36.80 -87.00 09/17/18Z 15 - TROPICAL DEPRESSION Wow...what could have been...thankfully was not. |
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You sure picked an interesting case study! Ethel formed in the central GOM on September 14th at 12Z at 23.9N 90.6W with sustained winds of 40 knots - based on observations from the automated marine platform. Unfortunately the Storm Summary does not give the time of the Recon report - just that it was in the afternoon. From the best track files, here is what Ethel did: 14/18Z 25.6 89.7 75 knots 15/00Z 27.0 89.1 110 knots 15/06Z 28.1 88.9 140 knots, pressure 981mb 15/12Z 29.1 88.9 80 knots 15/18Z 29.9 89.0 60 knots Ethel intensified 100 knots in 18 hours. When the dry air entrained into the system it significantly reduced the intensity, and fortunately this was prior to landfall (near Biloxi, Mississippi). But note the 06Z surface wind speed of 140 knots (160mph = Cat V) against a pressure of only 981mb. There are a few noted exceptions to the wind/pressure relationship, but in this case the surrounding pressure must have been uncommonly high. Since this storm was before the satellite era, Ethel must have continued her rapid intensification long after the Recon report and the core wind speed would have to have been extrapolated from ship reports or fixed platforms - its the only thing that I can think of to allow for such a high wind speed. And of course Ethel formed quite a bit more to the south of the current near-shore activity. Any other ideas out there? Cheers, ED |
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Ed, See if you can do this from memory, cause I'm too lazy today to look it up... Donna & Ethyl: back to back CAT V's. How many other times has this occurred? It would seem to me to be a very rare occurrence, no? Just curious. LI Phil |
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No, from memory I cannot recall another case, although I'm sure that one many have happened. Note: I moved this line of thought to the History Forum where it seems to be more appropriate. ED |
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Thanks. And this is the appropriate forum. It's amazing how throwing in a quick JB update can lead to a discussion of 1960 hurricanes. |
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I read it a little differently at Unisys Best Track ..it shows that the 981 pressure was during 09/15/00Z . When the winds were 110 That is the only time that a pressure was listed. There was not a pressure listed for the time when the winds were listed at 140 below is a cut/past form teh unisys besttrack page for Ethel Date: 14-17 SEP 1960 Hurricane ETHEL ADV LAT LON TIME WIND PR STAT 1 23.90 -90.60 09/14/12Z 40 - TROPICAL STORM 2 25.60 -89.70 09/14/18Z 75 - HURRICANE-1 3 27.00 -89.10 09/15/00Z 110 981 HURRICANE-3 4 28.10 -88.90 09/15/06Z 140 - HURRICANE-5 5 29.10 -88.90 09/15/12Z 80 - HURRICANE-1 6 29.90 -89.00 09/15/18Z 60 - TROPICAL STORM 7 30.70 -89.00 09/16/00Z 45 - TROPICAL STORM 8 31.30 -89.00 09/16/06Z 35 - TROPICAL STORM 9 32.00 -88.90 09/16/12Z 35 - TROPICAL STORM 10 32.90 -88.50 09/16/18Z 30 - TROPICAL DEPRESSION 11 33.90 -88.10 09/17/00Z 25 - TROPICAL DEPRESSION 12 35.00 -88.00 09/17/06Z 20 - TROPICAL DEPRESSION 13 36.00 -87.60 09/17/12Z 15 - TROPICAL DEPRESSION 14 36.80 -87.00 09/17/18Z 15 - TROPICAL DEPRESSION |
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Hmmm. I was using my old NOAA database file, but putting that pressure against the 15/00Z position sure makes more sense. I'll have to correct my database. Thanks, ED |