MASTER MASTER Oct 23

Storm Tides

in Twelve Tropical Cyclones

(including Four Intense New England Hurricanes)

Brian R. Jarvinen

National Hurricane Center, Retired

FOREWORD

Accompanying this document is a CD containing the following:

1. A PDF file of this document. 2. A .rex file for each one of the 12 storms. 3. A .stm or .trk file for each one of the 12 storms.

The .rex file can only be viewed in the SLOSH display program. It contains useful information for studying the storm surge in these hurricanes.

The .stm file contains the input data for the SLOSH model simulation at six hour intervals for 72 hours of track. This includes latitude, longitude, pressure drop and RMW. In some cases, hourly values before and after landfall may also be given.

The .trk file is an expansion of the .stm file to hourly values with extrapolations on each end of the track resulting in 100 hours of input data.

A SLOSH model simulation can be made from either the .stm or .trk file.

Cover Picture:

This picture shows the Edgewood Yacht Club (EYC) during the passage of hurricane Carol on August 31, 1954. The storm tide has risen up and flooded the building. Waves propagating on top of the storm surge are impacting the structure and causing further damage. The Yacht Club is located south of Providence, Rhode Island, near the head of Narragansett Bay. This photo was taken by C. Flagg.

TABLE OF CONTENTS SECTION 1 INTRODUCTION.................................................................1 SECTION 2 THE GREAT COLONIAL HURRICANE OF 1635..........................6 SECTION 3 THE GREAT SEPTEMBER GALE OF 1815................................13 SECTION 4 THE 1938 NEW ENGLAND HURRICANE.................................20 SECTION 5 HURRICANE CAROL (1954)..................................................26 SECTION 6 COMPARISON OF FOUR INTENSE HURRICANES THAT

AFFECTED NEW ENGLAND.................................................30 SECTION 7 THE SEA ISLAND HURRICANE OF 1893.................................33 SECTION 8 THE 1935 LABOR DAY HURRICANE......................................48 SECTION 9 COMPARISON OF OBSERVED AND SLOSH MODEL

STORM TIDE IN TROPICAL STORM ISIDORE (2002).................56 SECTION 10 COMPARISON OF OBSERVED AND SLOSH MODEL

STORM TIDE IN HURRICANE LILI (2002)...............................63 SECTION 11 HURRICANE AUDREY (1957)...............................................68 SECTION 12 THE 1900 GALVESTON HURRICANE.....................................76 SECTION 13 THE 1915 GALVESTON HURRICANE.....................................87 SECTION 14 HURRICANE ALICIA (1983)..................................................92 REFERENCES.....................................................................................97 ACKNOWLEDGEMENTS.......................................................................99

SECTION 1

A LOOK AT THE STORM TIDES IN TWELVE TROPICAL CYCLONES INCLUDING FOUR INTENSE NEW ENGLAND HURRICANES

BRIAN JARVINEN (RETIRED)

NOAA/TROPICAL PREDICTION CENTER/NATIONAL HURRICANE CENTER

OCTOBER 1, 2006

INTRODUCTION

The United States Atlantic and Gulf of Mexico coastlines have repeatedly been modified and reshaped by hurricane storm tides over the years. Since the arrival of immigrants from Europe, the coastline has steadily been developed with the addition of many homes and other buildings and an ever increasing coastal population. The consequences of this increase are visible, with each passing year, as hurricanes make landfall at different locations. However, for a specific location along the coast the frequency of an intense hurricane impact is low. Decades may pass between intense storms and in some locations such as New England; there may be hundreds of years between storms. Having an accurate historical data base on the most intense hurricanes is one of the main goals of hurricane research. One of the problems until the advent of reconnaissance flights into hurricanes in the 1940's was determining an intensity at landfall. Early sixteen and seventeen hundred eye-witness accounts of destruction from wind forces tell us little about the intensity. When wind and pressure measuring sensors began appearing in the nineteenth and twentieth centuries they rarely measured near the core of a hurricane where the maximum winds occur. Even when they were in the right place to measure the strongest winds, the device or its support mechanism failed. This problem still plagues us today. Some historical hurricanes had sea-level pressure readings taken as the center passed over and are excellent measures of the intensity. However, almost all of the historical accounts make reference to elevated water levels. Since these water levels are generated by the wind and pressure forces in the hurricane it is yet another measure of intensity. So if one can use a combined storm surge and astronomical tide model and reproduce the observed high water levels then one can deduce the intensity; both sea-level pressure in the eye as well as the maximum wind speed. This will be done for several of the early hurricanes, specifically the Great Colonial hurricane of 1635 and the Great September Gale of 1815. Two other intense hurricanes that impacted New England will also be analyzed: the 1938 hurricane and hurricane Carol in 1954. Seven additional hurricanes and one tropical storm will also be included and each will have its own section in this report.

The purpose of this report is to investigate the storm tides reported in each hurricane as well as the intensity at landfall. The hope is that this information will aid emergency management agencies at the federal, state and local level along with individuals residing along the coast to make proper life and property saving decisions when similar hurricanes threaten the region in the future.

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PROCEDURE

Each hurricane will have a summary of available meteorological and hydrologic data. A discussion of the meteorological data and its use in determining the track, intensity and size (i.e. radius of maximum winds) will follow. Next, a numerical storm surge model will be used to simulate each hurricane's maximum storm surge for the region of interest. In addition, a tide prediction program will also be used to determine the stage of the astronomical tide during the storm surge event so that an accurate comparison can be made to high water marks, which are a combination of both phenomena. Finally, a table showing a comparison of the maximum storm surge and intensity of the hurricanes will be made. First, a brief description and discussion of the dominant water elevating forces present in a hurricane will be made as well as the high water marks that they produce. Also, a description of the numerical storm surge model will be made.

STORM SURGE

Storm surge is the abnormal rise of water caused by the wind and pressure forces in a hurricane. The dominant of these two forces is the wind. Some of the wind's energy is transferred to the water to form waves. The waves, in turn, transfer some of their energy downward to form currents. In the deep ocean these currents rotate about the hurricane with little effect on water elevation. However, as the hurricane tracks toward a coastline, it first encounters the continental shelf and the currents, especially on the right side of the hurricane, begin to be slowed and compressed resulting in a rise of water which is the storm surge. As the hurricane continues toward landfall at the coastline and moves inland, the process continues and the height of the storm surge increases. In addition, the funneling or squeezing effect of bays and estuaries enhances the storm surge and in many cases the maximum heights are found at the heads of these bays and estuaries. This will readily become apparent from the data and analyses of these hurricanes.

ASTRONOMICAL TIDE OR TIDE AND MEAN SEA LEVEL

The astronomical tide, or tide for short, is an oscillation in the ocean caused by the gravitational attraction of the moon and sun on the earth. For most of the east coast of the United States the tide is semi-diurnal. This means that generally there are two high tides and two low tides each day. People living on or near the coast are usually aware of how high and how low these tide levels reach. This was especially true in the early colonial period when almost all travel was done by ship, boat and canoe. The tides, with their associated tidal currents, helped or hindered travel. Somewhat more difficult to locate is the mid-point of the tide or mean tide. The mean tide location is closely related to mean sea level Mean sea level is often referenced as zero elevation for the land and for our purposes, the water surface also. So another way of looking at the tide is that it oscillates up and down relative to mean sea level. For example, if the tide rose from low tide to high tide and the vertical distance traveled was four feet, then we could also say that it rose from minus two feet below mean sea level to plus two feet above mean sea level.

In 1929, mean sea level was determined using tide gage records along the North American coastlines. This was called the North Atlantic Vertical Datum of 1929 or NGVD for short. All land elevations were referenced to this datum. In our example above the tide would have risen

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