On 07SEP95, Hurricane Luis intensified from about 100 kt winds and 940 mb minimum sea-level pressure (MSLP) to 120 kt and 935 mb MSLP as it moved northwestward away from the Lesser Antilles. During the course of the day (UT) an outer concentric eyewall formed surrounding the original eyewall at 50 nmi radius. Early on 08SEP95, the new eyewall became the dominant feature and the maximum winds decreased to about 100 kt again. Natural eyewall cycles such as Luis’ are virtually identical to the expected result of the STORMFURY modification experiments carried out in the 1960s. Two radar composites transmitted in real time from a NOAA research aircraft to forecasters at the OAR show Luis’ well defined outer eyewall surrounding the dissipating partial inner eyewall

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Lili originated from a tropical wave that moved over the tropical Atlantic Ocean from the west coast of Africa on September 16th. The wave developed a low -level cloud circulation center midway between Africa and the Lesser Antilles on the 20th. Convective clouds became sufficiently well organized on the 21st 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. Graphs of best-track maximum one-minute surface wind speed and minimum central surface pressure, as a function of time. The six-hour best track positions and intensities are listed in.

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 23rd and then its winds briefly reached 60 knots on the 24th. The storm weakened to an open tropical wave on the 25th and 26th in the east-central Caribbean as its organization was disrupted by vertical wind shear.

Lili re-acquired a low-level closed circulation on the 27th, then its forward speed slowed to about 5 knots by the 28th 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 30th, 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 1st , 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 3rd, with an estimated 80-knot maximum wind speed. However, between Cuba and Louisiana, Lili intensified to 125 knots early on the 3rd 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 4th 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.

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