Hurricane Luis - Meteorological History

Meteorological History

The origins of Hurricane Luis trace back to an area of disturbed weather associated with a tropical wave over the eastern Atlantic Ocean on August 26. A low-level circulation center formed and moved westward until it developed a weak surface low on August 27; consequently, a tropical depression was designated at 1200 UTC that day. The depression attained 36 hours later into an Tropical Storm named "Luis" on August 29. Though convective activity fluctuated for the next two days as a result of nearby wind shear, the storm slowly intensified while pressure rose. The shear relented the next day, allowing an eye to gradually form, and the system attained hurricane status thereafter on early August 31 then a Category 3 major hurricane 18 hours later.

Hurricane Luis continued to strengthen as it tracked west-northwestward into a Category 4 on the Saffir-Simpson Hurricane Scale on September 2 and the cyclone turned more towards the west earlier that day as it maintained a rectilinear slow motion. on September 3, a reconnaissance aircraft confirmed that the storm, that reached Category 4 status earlier, peaked with 140 mph (230 km/h) and maintained it for two days and a half. At this time, it was located approximately 540 miles (870 km) to the east of the Lesser Antilles. As a result, the storm grew as it moved along a subtropical ridge due to the absorption of Karen by the stronger Iris.

By the evening of September 4, Luis sustained a very large wind field with tropical storm-force winds extending outward up to 350 mi (560 km) of the center as it moved very near Antigua and then directly passing over Barbuda while weakened slightly on the morning of September 5. Islands such as Dominica and even Guadeloupe, where it experienced hurricane-force winds on the northeastern coast, has been relatively spared by the storm. During the time, it proceeded northwestward affecting Montserrat, Saint Kitts and Nevis, Sint Eustatius and Saba causing moderate damage. Later, Luis moved along St. Barthelemy, St. Martin and ultimately crossed Anguilla, where maximum sustained winds within the eyewall were estimated to have reached 135 mph (217 km/h), and its central pressure had dropped from 945 to 942 mbar (27.9 to 27.8 inHg).

A large and powerful hurricane, Luis retained Category 4 intensity until September 7, situated about 150 mi (240 km) to the north of Puerto Rico. The storm gradually re-curved over the northern Atlantic as a Category 2 after having spent 7 consecutive days as a major hurricane. From there on, the center of the storm passed 200 miles (320 km) to the west of Bermuda on September 9 causing minor damage, and then later weakened to a Category 2 hurricane, with winds of 110 mph (165 km/h). Several hours later, the hurricane made its closest approach to Bermuda, passing about 200 mi (320 km) west of the island. Later that day, the storm began to accelerate as it traveled northeast ahead of a strong trough located to the northwest of Luis. During the afternoon of September 10, Hurricane Luis began to undergo an extratropical transition as it rapidly approached the Canadian coastline. Due to the rapid movement of the storm, significant weakening did not occur until Luis was at an unusually high latitude as the central pressure of the storm decreased to 961 mbar (28.38 inHg) but sustained winds did not exceed 90 mph (140 km/h) according to the NHC.

Luis maintained this intensity until it made landfall on the Avalon Peninsula in eastern Newfoundland early on September 11. While tracking over Newfoundland, cold, dry air became entrenched in Luis's circulation and the system began to merge with the approaching trough. The NHC issued their final advisory on Hurricane Luis at 0900 UTC on September 11 as it tracked nearly 65 mph (100 km/h) to the northeast and transitioned into an extratropical cyclone on September 11 as it moved ashore on eastern Newfoundland. The extratropical remnants persisted for 30 more hours over the North Atlantic Ocean before being absorbed by the trough near the southern coast of Greenland late on September 12.