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Atlantic Hurricane Variability

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Atlantic Hurricane Variability Powered By Docstoc
					        The Atlantic Hurricane Database
    Re-analysis Project – Results for 1851 to
      1910 and 1992’s Hurricane Andrew
                           Chris Landsea
                   NOAA/Hurricane Research Division
                        Miami, Florida, USA
                            CSU/CIRA
                          April 2nd, 2004
 Co-Authors: Craig Anderson, Noel Charles, Gil Clark, Peter Dodge, Jason Dunion,
Jose Fernandez-Partagas, James Franklin, Paul Hungerford, Charlie Neumann, Mark
              Zimmer, and the NHC Best Track Change Committee
   Acknowledgments: Sim Aberson, Auguste Boissonnade, Emery Boose, Mike
 Chenoweth, Hugh Cobb, Jose Colon, Neal Dorst, Paul Hebert, Brian Jones, Lorne
Ketch, Cary Mock, Ramon Perez Suarez, David Roth, Al Sandrik, and David Vallee.
          The Atlantic Hurricane
       Database Re-analysis Project
 What is the historical hurricane database
  and how is it utilized?
 Why revise HURDAT and how is it done?
 Databases provided
 Results thus far:
     – Example: The 1886 Indianola Hurricane
     – 1851 to 1910
     – Hurricane Andrew
    Acknowledgment: NOAA grant (NA7P0369), a grant from the Risk Prediction
       Initiative and supplemental funding from the Insurance Friends of NHC
 Track and
 Intensity NOAA   Dork Logo
  Forecast
Development
    and
Verification
Climate Variability and Change Studies
Building Codes and
 Insurance Rates
   HURDAT -
  Developed in the
    late 1960s in
support of the Apollo
   space program
Hurricane Bret (1999)
Intensity Estimates and “Best Track” Values
Center Fix and “Best Track”
Smoothed Representation in Best Track




Jarvinen et al. (1984)
Observational Platforms for Atlantic Hurricanes




            Neumann et al. (1999)
 Incorrect
  intensity
and location
 at landfall
Too Rapid During
  Last 6 Hours
Pressure-Wind
 Relationship
          Atlantic Major Hurricanes


                      Bias-removed




Landsea (1993)
 GPS Dropsondes
Measures the wind around and in hurricanes
 from the aircraft to the ocean’s surface


Wind in Hurricane Georges    Mean Wind Profile




 Franklin and Black (1999)
           Work of Jose Partagas:
Historical Reconstruction from 1851-1910
 Ship
Tracks
 Using Ship
Observations to
 Estimate the
 Hurricane’s
  Location
 Estimating Intensity with and
without Aircraft Reconnaissance
  The Beaufort Wind Scale
Beaufort Knots   Description     Number
 0        <1     Calm
 1       1-3     Light air
 2       4-6     Light breeze
 3       7-10    Gentle breeze
 4       11-16   Moderate breeze
 5       17-21   Fresh breeze
 6       22-27   Strong breeze
 7       28-33   Near gale
 8       34-40   Gale
 9       41-47   Strong gale
10       48-55   Storm
11       56-63   Violent storm
12       > 63    Hurricane
 ATLANTIC WIND/PRESSURE RELATIONSHIPS
           Winds (knots) computed from regional P/W relationships

1)For GLFMEX: Wind(knots)=10.627*(1013-p)**0.5640 Sample size =664; r=0.991
2)For <25N Wind(knots)=12.016*(1013-p)**0.5337 Sample size =1033; r=0.994
 3)For 25-35N Wind(knots)=14.172*(1013-p)**0.4778 Sample size =922; r=0.996
 4)For 35-45N Wind(knots)=16.086*(1013-p)**0.4333 Sample size =492; r=0.974
   5)For Kraft Wind(knots)=14.000*(1013-p)**0.5000 Sample size =13; r= ??


    P(MB) GLFMEX        <25N    25-35N 35-45N KRAFT         P(MB) P(IN)
     960       100      100       94      90      102       960 28.35

      Estimating the Central Pressure
         (Pr – Pc)/(Pe – Pc) = exp(-RMW/R)
Storm Surge
Surveys of Wind-caused Damage
             Metadata File for Storm #5, 1886:
             Estimated central pressure from Ho (1989) of 915 mb at landfall in Texas is incorrect since it
relied upon a pressure measurement from San Antonio, Texas, which has been found to be a surface
pressure rather than a sea level pressure value. Additionally, it is likely that this was not a central
pressure measurement either as strong winds were still observed at the time of lowest pressure and that
winds only shifted from northeast to southeast. This sea level pressure measurement of 971 mb
(corrected from the 948 mb surface pressure value) at 19Z on the 20th implies a central pressure of
around 965 mb, assuming that the RMW estimate of Ho (of 12 nmi) is slightly too small (15 nmi
utilized instead). 965 mb suggests winds of 94 kt from the Gulf of Mexico wind-pressure relationship
for a marine exposure - 85 kt utilized in best track for this inland location. Using methodology in Ho et
al. (1987) as modified by B. Jarvinen (personal communication), a 6.5 hr transit time from landfall to a
position near San Antonio, and the 965 mb central pressure near San Antonio, a new value of 925 mb at
landfall is estimated for this hurricane. This suggests winds of 133 kt from the Gulf of Mexico wind-
pressure relationship. The estimate of 15 nmi for RMW is slightly smaller than climatology (18 nmi)
for this latitude and central pressure (Vickery et al. 2000), supporting slightly stronger winds for this
particular storm. 135 kt is chosen as the maximum sustained winds at landfall. This is consistent with
the very high storm tide and extreme destruction in Indianola, Texas. Storm surge modeling efforts
with the SLOSH model (B. Jarvinen, personal communication) indicate that a 925 mb central pressure
and RMW of 15 nmi provides reasonable matches to observed surge values. Positions are altered
slightly after landfall to better account for passage of the hurricane's center near San Antonio at 19Z on
the 20th. A storm tide of 15' was reported for Indianola, Texas in Roth (1997b).
                 Center Fix Data for 1886/5:
1886/05 (Synoptic/intensity):
Date         Time        Wind/Dir    Pressure     Location    Source
8/14/1886 ???? UTC 80 kt/ESE-SW ???? mb 17.7N 67.5W "Gertie M. Rickerson"
8/15/1886 0700 UTC ? kt/N-SE         1000 mb 18.8N 70.0W Santo Domingo
8/17/1881 2000 UTC 50 kt/NE-WS           ???? mb 22.5N 80.0W Cardenas
8/18/1880 ???? UTC 50 kt/NE-SE       1005 mb      24.8N 82.0W Key West
8/18/1886 0900 UTC 70 kt/NE-S            994 mb 24.0N 82.5W "Manhattan"
8/19/1886 0700 UTC 60 kt/NE-SE       ???? mb      24.8N 83.0W "Arbutus"
8/20/1886 1400 UTC 70 kt/E               999 mb   28.4N 96.8W Indianola
8/20/1886 1930 UTC ? kt/??               971 mb   29.6N 98.5W San Antonio


1886/05 (Center positions):
Date     Time    Location       Source
8/20/1886 1930 UTC 29.6N 98.5W San Antonio
   Revised “Best Track” (HURDAT) Data for 1886/05:
Month Day Hour      Lat.   Long.   Dir.   --------Speed---------   ---------Wind-----------   Pres. ------------Type-----------

August   19 0 UTC 25.6N 87.9W 280 deg 16 kt 18 mph 29 kph 80 kt 95 mph 150 kph                 -- mb Hurricane - Category 1
August   19 6 UTC 25.9N 89.7W 280 deg 16 kt 18 mph 29 kph 90 kt 105 mph 170 kph               -- mb Hurricane - Category 2
August   19 12 UTC 26.3N 91.9W 280 deg 20 kt 23 mph 37 kph 100 kt 115 mph 180 kph             -- mb Major Hurricane - Category 3
August   19 18 UTC 26.5N 93.3W 280 deg 12 kt 13 mph 22 kph 110 kt 130 mph 210 kph             -- mb Major Hurricane - Category 3
August   20 0 UTC 26.8N 94.5W 285 deg 11 kt 12 mph 20 kph 120 kt 140 mph 230 kph              -- mb Major Hurricane - Category 4
August   20 6 UTC 27.4N 95.6W 300 deg 11 kt 12 mph 20 kph 130 kt 150 mph 250 kph              -- mb Major Hurricane - Category 4
August   20 12 UTC 28.0N 96.6W 305 deg 10 kt 11 mph 18 kph 135 kt 155 mph 260 kph 925 mb Major Hurricane - Category 4
August   20 18 UTC 28.8N 97.6W 310 deg 11 kt 12 mph 20 kph 85 kt 100 mph 160 kph 965 mb Hurricane - Category 1
August   21 0 UTC 29.7N 98.4W 320 deg 11 kt 12 mph 20 kph 60 kt 70 mph 110 kph                -- mb Tropical Storm
August   21 6 UTC 30.8N 99.3W 325 deg 13 kt 14 mph 24 kph 50 kt 60 mph 90 kph                 -- mb Tropical Storm
August   21 12 UTC 32.0N 100.0W 335 deg 13 kt 14 mph 24 kph 35 kt 40 mph 60 kph               -- mb Tropical Storm
August   21 18 UTC 33.5N 101.3W 325 deg 18 kt 20 mph 33 kph 25 kt 30 mph 50 kph               -- mb Tropical Depression
               U.S. Landfalling Hurricanes
#/Date      Time Lat    Lon Max SS# RMW Storm Central States
                            Wind        Surge Pressure Affected

5-8/20/1886 1200Z 28.0N 96.6W 135kt 4   15nmi   ---   925mb   BTX4
Minutes of the NHC best-track change commmittee meeting

Members Jack Beven, Jim Gross, Richard Pasch, Ed Rappaport, and chair (Colin McAdie) present. (meeting 5 –
22 March, 2002)


The committee met to continue consideration of the most recent set of best-track changes provided by Chris
Landsea et al. The committee resumed discussion with storm 1 of 1897, as agreed, completed discussion on the
second third (1890-1899) of the material and then proceeded through storm 5 (becoming 6) of 1901.
Jack Beven noted that the use of 3- or 4-cup anemometers in the early portion of the record could affect wind
estimates. Although there may be a systematic way to handle this, it is not clear whether this has been accounted
for.
 < Yes, this has been accounted for as best possible. In use during the period being revised - 1851 to 1910,
   though anemometers were mainly available from the 1870s onward at coastal stations - was the four
   cup Robinson anemometer. However, the primary difficulties with this instrument were its calibration and its
   mechanical failure in high wind conditions. Even as late as 1890, the highest wind that could be reliably
   calibrated with this instrument was only about 30 kt (from a whirling machine), due to lack of a strict
   comparison with a known quantity of stronger winds (Fergusson and Covert 1924)…. >
     Estimated average position and intensity errors in best track for
     the years 1851-1910. Negative bias errors indicate an
      underestimation of the true intensity.
     _________________________________________________________________________

     Situation    Dates          Position        Intensity Error Intensity Error
                                 Error           (absolute)      (bias)
     _________________________________________________________________________
     Open ocean 1851-1885        120 nmi/220 km 25 kt/13 m s-1   -15 kt/-8 m s-1
                 1886-1910       100 nmi/185 km 20 kt/10 m s-1   -10 kt/-5 m s-1

     Landfall in    1851-1885    120 nmi/220 km   25 kt/13 m s-1   -15 kt/-8 m s-1
     unsettled area 1886-1910    100 nmi/185 km   20 kt/10 m s-1   -10 kt/-5 m s-1

     Landfall at  1851-1885      60 nmi/110 km   15 kt/8 m s-1   0 kt/0 m s-1
     settled area 1886-1910      60 nmi/110 km   12 kt/6 m s-1   0 kt/0 m s-1
     __________________________________________________________________________
__
Strongest U.S. Hurricane – 1851 to 1910
Most Intense (Category 3, 4, 5) Continental United States Hurricanes: 1851-
1910
#/Date      Time Lat Lon                       Max Saffir-   Storm      Central    States
                                    Winds Simpson Surge      Pressure   Affected

5-8/20/1886 1300Z 28.1N 96.8W       135kt 4     15'          925mb      BTX4
1-8/10/1856$            1800Z 29.2N 91.1W       130kt 4      11-12'%    934mb      LA4
1-9/9/1900 0140Z 29.1N 95.1W        125kt 4     20'%         936mb      CTX4
10-10/2/1893            0800Z 29.3N 89.8W       115kt 4      ---        948mb      LA4
7-10/2/1898 1600Z 30.9N 81.4W       115kt 4     16'          938mb      GA4,DFL2
6-9/16/1855$            0300Z 29.2N 89.5W       110kt 3      10-15'%    (950mb)    LA3,MS3
1-8/11/1860$            2000Z 29.2N 90.0W       110kt 3      12'%       (950mb)    LA3,MS3,AL2
4-9/1/1879$ 1600Z 29.5N 91.4W       110kt 3     ---          (950mb)    LA3
2-8/13/1880#            0100Z 25.8N 97.0W       110kt 3      ---        931mb      ATX3
3-8/16/1888$            1900Z 25.8N 80.1W       110kt 3      14'%       (945mb)    CFL3,BFL1
4-9/29/1896 1100Z 29.2N 83.1W       110kt 3     ---          960mb      AFL3,DFL3,GA2,SC1,NC1,VA1
10-10/12/1886 2200Z 29.8N 93.5W     105kt 3     12'%         (955mb)    LA3,CTX2
9-10/13/1893            1300Z 33.0N 79.5W       105kt 3      14'%       955mb      SC3,NC2,VA1
5-10/9/1894 0300Z 30.2N 85.5W       105kt 3     ---          (955mb)    AFL3,GA1
3-8/18/1899 0100Z 35.2N 75.8W       105kt 3     ---          (945mb)    NC3
8-10/18/1906            0930Z 24.7N 81.1W       105kt 3      ---        953mb      BFL3,CFL3
8-9/21/1909 0000Z 29.5N 91.3W       105kt 3     15'%         952mb      LA3,MS2
4-8/23/1851$            2100Z 30.1N 85.7W       100kt 3      12'%       (960mb)    AFL3,GA1
1-8/26/1852 0600Z 30.2N 88.6W       100kt 3     12'%         961mb      AL3,MS3,LA2,AFL1
2-9/8/1854 2000Z 31.7N 81.1W        100kt 3     ---          950mb      GA3,SC2,DFL1
6-9/8/1869 2200Z 41.4N 71.7W        100kt 3     8'%          965mb      RI3,MA3,CT1
3-8/17/1871$            0200Z 27.1N 80.2W       100kt 3      ---        955mb      CFL3,DFL1,AFL1
5-10/7/1873$            0100Z 26.5N 82.2W       100kt 3      14'%       959mb      BFL3,CFL2,DFL1
3-9/16/1875 2100Z 27.7N 97.2W       100kt 3     15'%         (960mb)    BTX3,ATX2
4-10/3/1877$            0500Z 30.0N 85.5W       100kt 3      12'%       (960mb)    AFL3,GA1
2-8/18/1879 1200Z 34.7N 76.7W       100kt 3     7'           971mb      NC3,VA2
2-9/10/1882 0200Z 30.4N 86.8W       100kt 3      ---         949mb      AFL3,AL1
2-8/25/1885 0900Z 32.2N 80.7W       100kt 3     ---          (953mb)    SC3,NC2,GA1,DFL1
6-8/28/1893 0500Z 31.7N 81.1W       100kt 3     9-10'        954mb      GA3,SC3,NC1,DFL1
4-7/21/1909 1650Z 28.9N 95.3W       100kt 3     10'%         959mb      CTX3
Longest lived hurricane on record
Four Hurricanes Simultaneously
 U.S. Deadliest
 Hurricanes of
the 19th Century
Busiest U.S. Hurricane Season on Record
Changes to U.S. Hurricanes - 1899 to 1910
#/Date       Original     2003 HURDAT Category/State
             HURDAT       Revision  Changes

2-8/1/1899 TS             AFL2       Upgrade by two categories
3-8/18/1899 NC3           NC3        No change
8-10/31/1899              NC3,SC3    NC2,SC2      Downgrade by a category
1-9/9/1900 CTX4           CTX4       No change
3-7/11/1901 NC1           NC1        No change
4-8/14-15/1901 LA2,MS2 LA1,MS1,AL1 Downgrade by a category, add in Alabama
1902 - No U.S. hurricanes
3-9/11&13/1903 CFL2,AFL1 CFL1,AFL1 Downgrade by a category in SE Florida
4-9/16/1903 NJ1,NY1       NJ1,DE1    No change in category, add in Delaware, remove New York
2-9/14/1904 SC1           SC1        No change
3-10/17/1904              TS         CFL1         Upgrade by a category
1905 - No U.S. hurricanes
2-6/17/1906 CFL1          BFL1,CFL1 No change in category, add in SE Florida
5-9/17/1906 SC3,NC3       SC1,NC1    Downgrade by two categories
6-9/27/1906 MS3,AL3       MS2,AL2,AFL2,LA1 Downgrade by a category, add in NW Florida and Louisana
8-10/18/1906              CFL2       BFL3,CFL3 Upgrade by a category, add in SW Florida
1907 - No U.S. hurricanes
3-7/31/1908 NC1           NC1        No change
2-6/29/1909 TS            ATX2       Upgrade by two categories
4-7/21/1909 CTX3          CTX3       No change
6-8/27/1909#              ATX2       ATX1         Downgrade by a category
8-9/21/1909 LA4           LA3,MS2    Downgrade by a category, add in Mississippi
10-10/11/1909 CFL3        BFL3,CFL3 No change in category, add in SW Florid
3-9/14/1910 ATX2          ATX2       No change
5-10/17/1910              BFL3       BFL2         Downgrade by a category

Notes: Overall: 2 hurricanes upgraded 2 categories, 2 hurricanes upgraded 1 category, 10 hurricanes no change
in category, 7 hurricanes downgraded 1 category, 1 hurricane downgraded 2 categories.
Incomplete
 Records
“Settled Area”
   In 1850
Busy Atlantic Seaboard Decade – The 1890s
Sandrik and Landsea (2003)
Three Major
 Hurricanes
 In Georgia
        Atlantic Hurricane Re-Analysis Project
        http://www.aoml.noaa.gov/hrd/data_sub/re_anal.html
                   1.  Re-analysis results for 1851 to 1910
                       a. Overview and Highlights
                       b. Documentation
                       c. Data
              2.   Hurricane Andrew's Upgrade
              3.   Books by Jose' Fernandez Partagas

    1911 through 1940 being re-analyzed currently (working with William
     Bredemeyer, Steve Feuer, John Gamache and Lenworth Woolcock)




Picture from: "Florida's Hurricane History", by Jay Barnes
NOAA Dork Logo
                                   But nobody lives
                                   at 10,000 ft.
                                   How can we use
                                   flight-level data to
     90 kt                         estimate surface
                    95 kt          winds?
   90 kt

                       105 kt




   RECON FLIGHT-LEVEL WINDS
HURRICANE GEORGES 9/20/98 20-23Z
In the early 1990’s,
reduction factors used by
NHC ranged from 75%-90%
of the flight-level wind.
Powell and Black (1990)
concluded 63-73% for
700mb to surface reduction
factor, but had few eyewall
high-wind cases.
           EYEWALL SCHEMATIC




                                                    AIRCRAFT
                                                    TRACK




                   DROPSONDE       100   90 80 70
10000 ft           TRAJECTORY




                                ~1-2 miles
AVERAGE OF 357 GPS
DROPSONDE PROFILES
IN THE HURRICANE
EYEWALL.


ON AVERAGE, THE
SURFACE WIND IS 90%
OF THE WIND AT 700 MB
AIRCRAFT
RECONNAISSANCE
LEVELS (75-80% AT
LOWER ALTITUDES).




  Franklin et al. (2002)
New H*WIND Analysis
 For Hurricane Andrew

      150 kt –
  93% of flight level
Some New Hurricane Andrew Data:
     Radar Feature Tracking
              The Re-analysis
        of Hurricane Andrew (1992)
   Flight-level wind to surface extrapolation   145 kt (+10)
   Feature tracking from the Miami radar        145 kt (+15)
   Pressure-wind relationships                  145 kt (+20)
   Satellite intensity estimates                145 kt (+20)
   Storm surge and SLOSH implications           145 kt (+25)

   Structural damage survey estimates           135 kt (+30)
Revised
Best Track
            A RE-ANALYSIS OF ANDREW’S INTENSITY

       1992’s Hurricane Andrew originally was assessed as a Category 4
hurricane, based primarily upon extrapolation of flight-level winds to the
surface.

       Research using GPS dropwindsondes in the late 1990s and early
2000s has demonstrated that stronger winds exist at the surface the
hurricane eyewall than originally believed.

        A re-analysis indicates that Hurricane Andrew reached Category
5 status at its landfall in both the northern Bahamas and in southeastern
Florida (145 kt +10 kt).

       Because of this reclassification, the return period of catastrophic
hurricanes like Andrew increases from about 30 years to around a
century for southeastern Florida. Thus the risk from Andrew-like
hurricanes there is significantly LESS than previously estimated.
          The Atlantic Hurricane
       Database Re-analysis Project
 What is the historical hurricane database
  and how is it utilized?
 Why revise HURDAT and how is it done?
 Databases provided
 Results thus far:
     – Example: The 1886 Indianola Hurricane
     – 1851 to 1910
     – Hurricane Andrew
    Acknowledgment: NOAA grant (NA7P0369), a grant from the Risk Prediction
       Initiative and supplemental funding from the Insurance Friends of NHC
“Settled Area”
   In 1890
      Atlantic Multidecadal Mode
     Local Correlation of SST versus REOF




Mestas-Nunez and Enfield (1999)
           Atlantic SST Multidecadal Mode (AMM) (rotated)
           0.6

           0.4

           0.2
SST (°C)




              0

           -0.2


           -0.4

           -0.6
                  1870
                  1874
                  1878
                  1882
                  1886
                  1890
                  1894
                  1898
                  1902
                  1906
                  1910
                  1914
                  1918
                  1922
                  1926
                  1930
                  1934
                  1938
                  1942
                  1946
                  1950
                  1954
                  1958
                  1962
                  1966
                  1970
                  1974
                  1978
                  1982
                  1986
                  1990
                  1994
                  1998
                        Annual means and    5-year RM for N. Atlantic Box
                               from Goldenberg et al.   Science , July 20, 2001
  WHAT IS THE INTENSITY OF A TROPICAL
CYCLONE AND HOW IS IT MEASURED TODAY?
 Maximum sustained surface wind: Maximum
  wind, averaged over 1 minute interval at an altitude
  of 33 ft (10 m), associated with the circulation of
  the tropical cyclone at a given point in time.
 With very, very few exceptions, direct observations
  of the maximum sustained surface wind in a
  tropical cyclone are not available.

 Satellite imagery using the Dvorak technique
    Aircraft reconnaissance flight-level winds
              GPS dropwindsondes
EYEWALL STRUCTURE
CAN VARY
SIGNIFICANTLY FROM
STORM TO STORM, OR
EVEN DURING
DIFFERENT STAGES OF
THE LIFE CYCLE OF A
SINGLE STORM.




Franklin et al. (2002)
         Step 1: Flight Level to a Mean Boundary Layer (0 to 500m)
           1.7
                                                                                   -1              3               -1              2               -1
                                                            UMBL = U700 [2.31x10        (R/RMW )       - 6.82x10        (R/RMW )       + 3.04x10        (R/RMW ) + 1.26]

           1.6                                                                                                                                          Apply pol ynomi al
                                                                                                                                                        if R/Rm ax <=2.0
                                                                                                                                                        and
           1.5                                                                                                                                          Apply x1.3 boos t
                                                                                                                                                        if R/Rm ax <0.25
                                                                                                                                                        and R/Rmax>=0
           1.4



 MBL       1.3


  to       1.2

700mb
           1.1
 Ratio
           1.0



           0.9
                       Bi n Ave (R/Rmax: 0.1 bins )
                       Data
           0.8
                              Inside Flight-Lev el
                                                                                                          Outside Flight Lev el
                              RMW
           0.7
                 0.2           0.4             0.6        0.8           1.0                 1.2                1.4                     1.6                 1.8               2.0



                                         Distance as a Function of RMW
                                                      Dunion, Landsea, Houston and Powell (2002); Dunion and Powell (2002)
                                                               Step 2: Mean Boundary Layer (0 to 500m) to the Surface
                                      1.10

                                                                                                                                   -7               3                -4               2                 -2
                                                                                                   U SFC = U MB L [-2.84x10             (U MB L )       + 1.58x10         (U MB L )       - 1.25x10          (U MB L ) + 1.08]


                                      1.00




                                      0.90
Surface Wind Speed / MBL Wind Speed




                                      0.80




                                      0.70
                                                 Use P BL model if
                                                                     -1
                                                 W MB L <55 ms

                                                 Apply polynomial
                                                                               -1
                                      0.60       if W   MB L   >=55 ms
                                                                     -1
                                                 and <=72 ms                                                                                                                                     Data
                                                 Use 0.9(W                                                                                                                                       Bin Ave (w/ 5 min gus t)
                                                                 MB L )   if
                                                 W MB L >72 ms
                                                                     -1                                                                                                                          HRD PB L Model
                                      0.50
                                             0                     10                    20                  30                    40                         50                      60                     70                  80
                                             0          10      20             30   40        50     60      70    80         90        100             110    120        130     140         150     160     170     180

                                                                                                             MBL Wind Speed (ms-1)                                                              Dunion, Landsea, Houston (2002);
                                                                                                             MBL Wind Speed (mph)                                                                  Dunion and Powell (2002)
   Hurricane Andrew -
Satellite Dvorak Estimates
      127 kt/935 mb
Hurricane Andrew’s
   Storm Surge
       And
  SLOSH Runs
     Structural Damage
Surveys of Hurricane Andrew

				
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