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Hurricane Dorian Relief; Green Turtle Cay & Marsh Harbor

Discussion in 'General Yachting Discussion' started by Irish Wake, Sep 3, 2019.

  1. olderboater

    olderboater Senior Member

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    I found this chart interesting. Just shows the force and how drastically things changed as Dorian went from CAT 1 to 2 to 3 to 4 to 5.

    Wind Damage.JPG
    Damage at 185 nearly 10 times that at 140 mph. Even 170 mph 20 times more than a 120 mph CAT 3. To my knowledge the information is not available, but I'd be very interested in measurements of it's wind speed on the ground in various locations. I think we'd see the difference reflected in the damage variables at different locations.

    A standard that's been used for decades in construction is building to withstand 150 mph winds. Even a CAT 5 seldom delivers more than that on the ground, or if it does it's a very small cut of land to receive it. However, Dorian hit buildings with force from 2 to 4 times that or more.

    I had never seen this chart before. I pulled it from the NWS.

    https://www.weather.gov/jetstream/tc_potential
  2. Pascal

    Pascal Senior Member

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    Interesting chart

    Duration is also critical and Dorian slow movement, like cat 5 Luis in 95 over St Barth’s and St Maarten, adds another layer of multiplier. Things that may hold 2 hours at 160mph will fail after 5 or more hours

    One thing often overlooked is vibration. I ve seen it personally like Hurricane shutters Lag screws into lead anchors in concrete backing out because of the vibrations. Same thing with nails. The vibration in a severe storm will get them loose

    I remember back in 89 when Hugo passed close to st Barth’s, we only got about 100mph. We had a 16” alum sat dish on top of the hill, it had light damage but every single bolt was loose
  3. Ken Bracewell

    Ken Bracewell Senior Member

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    Somewhere Sunny
    I spent three weeks in the Abacos, working with MV Pacific Hope. www.mvpacifichope.org
    Our effort at Grand Cay began when the Deputy Prime Minister directed me there with a small group of Doctors and Medical Professionals. We managed to open the local clinic, and saw nearly every one of the 300 residents on the island.
    We then focussed our efforts on providing water to the island via a small temporary water maker we set up, supplemented by 250 gallon totes that I was filling at the neighboring island of Big Grand Cay.
    Next we directed our resources toward cleaning the debris left from the Dorian, as well as preparing the homes and buildings for repairs. Luckily, one of our volunteers was a retired contractor who managed to put together a complete list of the needed building supplies and materials. These are being provided through donations, and Pacific Hope has recruited volunteer labor to rebuild the entire island of Little Grand Cay.
    Proud to have been a part of the whole operation.
  4. PacBlue

    PacBlue Senior Member

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    1st class relief effort, props to all!