Tropical Cyclone Report

Hurricane Lili

Hurricane Lili crossed western Cuba as a category two hurricane on the Saffir-Simpson Hurricane Scale and made landfall on the Louisiana coast as a category one hurricane. Lili also affected the Windward Islands as a tropical storm, the northeastern Cayman Islands as a category one hurricane and caused serious rainfall flooding in Jamaica. Thirteen deaths are attributed to Lili. Lili reached category four intensity over the Gulf of Mexico.

a. Synoptic History

Lili originated from a tropical wave that moved over the tropical Atlantic Ocean from the west coast of Africa on September 16^th. The wave developed a low -level cloud circulation center midway between Africa and the Lesser Antilles on the 20^th. Convective clouds became sufficiently well organized on the 21^st to qualify the system as a tropical depression, centered about 900 n mi east of the Windward Islands. The "best track" of the tropical cyclone's path starts at this stage and is shown in Figure 1. Graphs of best-track maximum one-minute surface wind speed and minimum central surface pressure, as a function of time, are shown in Figure 2 and Figure 3, respectively. The six-hour best track positions and intensities are listed in Table 1.

Lili's track followed the pressure contours of the southern and western periphery of the semi-permanent Atlantic subtropical high pressure ridge. The tropical cyclone moved just north of due westward at over 20 knots, crossed the Windward Islands as a developing tropical storm on the 23^rd and then its winds briefly reached 60 knots on the 24^th. The storm weakened to an open tropical wave on the 25^th and 26^th in the east-central Caribbean as its organization was disrupted by vertical wind shear.

Lili re-acquired a low-level closed circulation on the 27^th, then its forward speed slowed to about 5 knots by the 28^th while beginning a slow northward jog around the north coast of Jamaica. The storm dumped heavy rain on Jamaica and also Haiti. Resuming a west-northwestward track, Lili became a hurricane on the 30^th, while passing over Cayman Brac and Little Cayman Islands.

The center of the hurricane moved over the southwest tip of the Isle of Youth on the morning of October 1^st , and over western mainland Cuba a few hours later, with wind speeds as high as 90 knots. Gradually accelerating its forward speed to about 15 knots, Lily turned northward and made landfall on the Louisiana coast on the 3^rd, with an estimated 80-knot maximum wind speed. However, between Cuba and Louisiana, Lili intensified to 125 knots early on the 3^rd over the north-central Gulf of Mexico and then rapidly weakened to 80 knots during the 13 hours until landfall. Lili was absorbed by an extratropical low on the 4^th while moving northeastward near the Tennessee/Arkansas border. Lili was the first hurricane to make landfall in the United States since Irene hit Florida in 1999.

b. Meteorological Statistics

Observations used to estimate wind speed and pressure are plotted in Figure 2 and Figure 3, along with the best-track wind speed and pressure curves. These observations include satellite-based Dvorak technique intensity estimates from the Tropical Analysis and Forecast Branch (TAFB), the Satellite Analysis Branch (SAB) and the U. S. Air Force Weather Agency (AFWA), as well as flight-level and selected dropwindsonde observations from flights of the 53^rd Weather Reconnaissance Squadron of the USAF Reserve Command and from the NOAA Aircraft Operations Center.

Ship reports of winds of tropical storm force or higher are given in Table 2, and selected surface observations from land stations and data buoys are given in Table 3.

Sustained wind speeds were near 45 to 50 knots as Lili moved quickly across the Windward Islands. A sustained wind speed of 47 knots with a gust to 68 knots was observed at Martinique early on the 24^th.

The forward motion slowed to five knots as Lili moved between Haiti, Jamaica and eastern Cuba. This slow motion contributed to the copious rainfall over Jamaica from the 27^th through the 30^th, where over 20 inches of rainfall was recorded (Table 3). Haiti also received considerable rainfall.

Lili developed an eye which passed over the Isle of Youth and then western mainland Cuba on October 1^st. The highest wind report from Cuba was a ten-minute average of 87 knots with a gust to 98 knots from Francia on the Isle of Youth and this is the basis for a best-track wind speed of 90 knots over Cuba. The highest aircraft -measured flight-level wind speed during this time was 87 knots. Over six inches of rainfall was recorded at locations in Granma and Santiago de Cuba provinces in eastern Cuba.

The highest best-track wind speed is estimated at 125 knots at 0000 UTC on the 3^rd, while the hurricane was centered in the north-central Gulf of Mexico. This is based on an aircraft 700-mb flight-level wind speed of 142 knots along with 938-mb surface pressure. The aircraft flight level-wind speed reduces to a surface wind of 128 knots using a 90 percent eyewall reduction factor. There were also several GPS-sonde surface wind speed measurements of 115 to 123 knots near this time. The east eye wall passed over NOAA data buoy 42001 at 2000 UTC on the 2^nd. This buoy reported a ten-minute wind speed of 98 knots with a gust to 130 knots, which is the highest wind speed ever recorded by a National Data Buoy Center buoy.

Hurricane Lili made landfall along the south-central coast of Louisiana near Intracoastal City. The highest observed sustained wind over land is 64 knots (Table 3), from a Texas Tech. tower near Kaplan or about 15 n mi north-northwest of Intracoastal City. The highest recorded wind gust is 104 knots at Intracoastal City. The highest aircraft flight level wind speed near the time of landfall is 88 knots at 700 mb. The highest surface wind speed estimate obtained from GPS-sondes during the last few hours before landfall is 73 knots. A mobile SMART radar measured 101 knots just above the surface south of New Iberia. The lowest surface pressure observed was 963.9 mb at the Louisiana Agriclimate Information System at Crowley. Based on the above data, the best-track maximum wind speed at landfall is estimated at 80 knots. The landfall area is sparsely populated. Most of southern Louisiana experienced sustained winds of 65 knots or less.

Lili's eyewall collapsed as its wind speed decreased during the 13 hours before landfall. The radius of maximum wind speed may not have been close to the center at landfall. Aircraft Flight level winds near the coast just south of Morgan City suggest that the highest winds were perhaps 50 n mi east of the center, so that wind speeds near the coast south of Morgan City could have been as high or higher than wind speeds near Intracoastal City, where the center crossed the coast.

Rainfall across south-central and southeastern Louisiana ranged from four to eight inches, with the highest amount of 8.57 inches at Perry, just north of Intracoastal City. Over four inches was measured in northern Louisiana and southern Mississippi and over two inches spread into Arkansas. Portions of Florida and Alabama had over an inch of rain. A tide gage at Crewboat Channel near Calumet measured a storm tide water height of 12.3 feet and another at Vermillion Bay measured 11.7 feet. The water height at Burn's Point, south of Morgan City, is estimated at 10 to 12 feet above normal, based on the observed water level inside a house. A combination of storm surge and heavy rain caused levees to fail at Montegut and Franklin, Louisiana. Tide gauge waters levels were already 2 to 4 ft above normal prior to Lili's arrival.

Tornadoes were reported in Acadia, Evangeline, Lafayette, Rapides, and St. Landry Parishes. Most were short-lived and damage was in the F-0 to F-1 range on the Fujita scale.

c. Casualty and Damage Statistics

Lili went through the Windward Islands as a tropical storm. Landslides killed four in St. Vincent, including an infant. There was damage to 400 homes in Barbados and half the banana crop of St. Lucia was destroyed.

Jamaica was hard hit by heavy rain from Lili. Four people, including a 3-year-old child, died when flood waters swept them away. Flood waters also swept away livestock and crops and caused extensive damage to homes, bridges, roadways, and other infrastructure. Flood damage was compounded by heavy rain earlier in September from Hurricane Isidore. This is also the case with rainfall over western Cuba and Louisiana. Lili also pelted Haiti's south coast with wind and rain and four flood-related deaths occurred there.

There are news reports of high winds uprooting trees, knocking out electricity and damaging roofs in Cayman Brac in the northeastern Cayman Islands.

The hurricane cut a swath of destruction across western Cuba, damaging buildings and farmland and disrupting communications. Some 360,000 people were reported to have been evacuated from their homes. There was one direct death in Pinar del Rio province.

Lili made landfall on the central Louisiana coast as a category one hurricane and left behind a trail of muck and misery from widespread wind and flood damage. Strong winds toppled trees onto houses and into roadways, stripped shingles from roofs, and blew out windows. The wind and driving rain flattened sugar cane fields throughout southern Louisiana. A combination of storm surge and rain caused levees to fail in the southeastern part of the state. Lili also temporarily curtailed all oil production in the Gulf of Mexico. The latest insured property damage total from the American Insurance Services Group is $430 million U.S. dollars, $415 million for Louisiana and &15 million for Mississippi. The total dollar damage estimate is twice this value or $860 million dollars. President Bush declared that Louisiana is eligible for federal assistance.

One indirect fatality occurred in Crowley, Louisiana, when an elderly woman died from carbon monoxide poisoning from a generator. Another indirect fatality occurred in Vermilion Parish where a 79 year old Erath man died when he fell from a ladder cleaning up storm debris.

d. Forecast and Warning Critique

Table 4 is a listing of average errors (with the number of cases in parentheses) for official forecasts and for a selection of guidance models. The official track errors are between 30 and 48 percent lower than the average official track errors for the previous 10-yr period, also listed in Table 4. The GUNS and GUNA guidance consistently had smaller errors than the official forecast at all forecast periods. These two guidance models are equally-weighted combinations of the GFDI, UKMI, and NGPI models (GUNS) and of GFDI, UKMI, NGPI, and AVNI models (GUNA).

Average official intensity errors are near the previous 10-yr averages and are smaller than all of the guidance errors.

Table 5 lists the watches and warnings issued for Lili. The hurricane made landfall on the Isle of Youth, Cuba 20 h after hurricane warnings were issued and made landfall on the western Cuba mainland 23 hours after warnings were issued. Hurricane warnings were issued for coastal Louisiana 28 h before landfall.

Figure 1: Best track positions for Hurricane Lili, 21 September - 4 October 2002.

Figure 2: Selected wind observations and best track maximum sustained surface wind speed curve for Hurricane Lili, 21 September - 4 October 2002. Aircraft observations have been adjusted for elevation using 90%, 80%, and 80% reduction factors for observations from 700 mb, 850 mb, and 1500 ft, respectively. Dropwindsonde observations include surface estimates derived from the mean wind over the lowest 150 m of the wind sounding (LLM) and from the sounding boundary layer mean (MBL).

Figure 3: Selected pressure observations and best track minimum central pressure curve for Hurricane Lili, 21 September - 4 October 2002.