 Track of Laura, according to theSaffir–Simpson scale | |
| Meteorological history | |
|---|---|
| Formed | August 20, 2020 |
| Dissipated | August 29, 2020 |
| Category 4 major hurricane | |
| 1-minute sustained (SSHWS/NWS) | |
| Highest winds | 150 mph (240 km/h) |
| Lowest pressure | 937mbar (hPa); 27.67 inHg |
| Overall effects | |
| Areas affected | Lesser Antilles,Greater Antilles,The Bahamas,Gulf Coast of the United States,Midwestern United States,Eastern United States |
Part of the2020 Atlantic hurricane season | |
| History Effects Other wikis | |
Hurricane Laura tied the record for the strongesthurricane to makelandfall in Louisiana as measured bymaximum sustained winds, along with the1856 Last Island hurricane andHurricane Ida, and was overall the tenth-strongest hurricane to make landfall in theUnited States. The thirteenthtropical cyclone, twelfthnamed storm, fourth hurricane, and first major hurricane of the2020 Atlantic hurricane season, Laura originated from a largetropical wave that moved off theWest African coast on August 16. The tropical wave gradually organized, becoming a tropical depression on August 20. Though in only a marginally conducive environment for intensification, the depression nevertheless intensified into a tropical storm a day later, becoming the earliest twelfth named storm on record in the North Atlantic basin, forming eight days earlier than 1995'sHurricane Luis. The depression received the nameLaura and tracked west-northwest towards theLesser Antilles.
Laura first hit the Lesser Antilles and brushedPuerto Rico as a tropical storm, before it moved across the island ofHispaniola. The storm killed 21 people inHaiti and four in theDominican Republic. The storm later moved across the length of Cuba, while maintaining its intensity as convection was mainly to the south of the island, although its outer rainbands extended into theFlorida Keys andSouth Florida. Laura moved across theGulf of Mexico, strengthening slowly at first, before a period ofrapid intensification began on August 26. That day, Laura became a major hurricane, and later attained peak winds of 150 mph (240 km/h), making it a strongCategory 4 hurricane, with its pressure bottoming out at 937 mbar (27.7 inHg). Early on August 27, Laura made landfall near peak intensity onCameron, Louisiana with 150 miles per hour (240 km/h) winds, with a minimum central pressure of 939 mbar (27.7 inHg). It quickly weakened over land, degrading to a tropical storm overNorthwestern Louisiana before dropping to tropical depression status nearPine Bluff, Arkansas on August 28. It turned eastward and became a remnant low overKentucky on August 29 before being absorbed by anextratropical low overMaryland several hours later.
On August 16, a large tropical wave moved off the coast of Africa.[1] The same day, the National Hurricane Center noted the possibility of tropical development as the wave neared more favorable conditions, with the 5-day development chance being estimated at 20%.[2] The next day, the wave entered more favorable developmental conditions and the NHC raised the 5-day development chance to 50%.[3] It then merged with another disturbance to its west and alow-pressure area formed, prompting the NHC to raise the 5-day development potential to 90%.[4] The low continued to slowly organize with rainbands apparent and a well-defined low-level center forming. By 00:00 UTC on August 20, the low had organized enough to be designated asTropical Depression Thirteen and advisories were initiated on the storm three hours later. At the time, it was located around 850 miles (1,370 km) east-southeast ofAntigua. TheBermuda High over the Central Atlantic built westward, which in turned steered the system west-northwestward.[5] The system would be steered around this ridge for its entire existence.[6] Environmental conditions featured mixed signals for intensification, including lowwind shear and dry air from theSaharan Air Layer. Accordingly,forecast models displayed solutions ranging from the system degrading back into a tropical wave all the way to becoming amajor hurricane within the next five days.[7]
Initialaircraft reconnaissance into the system late on August 20 into August 21 revealed a poorly organized system with an ill-defined, elongated surface low.[8] Furthermore, the system's mid-level circulation was displaced several hundred miles southeast of the assumed surface circulation. During the early part of August 21, the depression may have degenerated into a tropical wave, although the NHC continued to issue advisories on the system.[9] The depression continued to struggle because of significant mid-level wind shear, dry air, and its fast forward motion of over 20 mph (32 km/h).[10] However, a Hurricane Hunters flight on August 21 observed gale-force winds and a center farther south then previously estimated. Consequently, the National Hurricane Center upgraded the depression to a tropical storm and named itLaura at 13:05 UTC; post-storm analysis determined that the system had become a tropical storm around 12:00 UTC.[11][1] This made Laura the earliest twelfth named Atlantic storm ever recorded, beating the record ofHurricane Luis of1995 by eight days. At the time, Laura was located around 230 miles (370 km) east-southeast of the northern Leeward Islands and had maximum sustained winds of 45 mph (72 km/h) and a minimum central pressure of 1,007 mbar (29.7 inHg). Despite being stronger, Laura remained poorly organized due to moderate wind shear as it moved over the Leeward Islands, with most of its convection and strongest winds located north and east of the center of circulation.[12] Continuing west-northwestward with no change in strength, Laura made its first landfall in Antigua around 20:30 UTC before making landfall inNevis around 23:30 UTC.[1] Eventually, Laura became slightly better organized and it strengthened a little as it passed south ofPuerto Rico, although its center remained elongated.[13][14] During the afternoon of August 22, a strongmesocyclone within the storm's broader circulation impacted Puerto Rico; sustained winds associated with this feature reached 60 mph (97 km/h) inLas Marías, although this was not representative of the storm's actual intensity.[15] Laura then madelandfall nearSan Pedro de Macorís,Dominican Republic at around 04:30 UTC on August 23 with 1-minute sustained winds of 50 mph (80 km/h) and a pressure of 1004mbars (29.64inHg).[1]
Despite moving over rugged, mountainous terrain, normally an impediment to tropical cyclone organization, the large size of Laura as well as its lack of inner core allowed it to maintain most of its intensity as it moved overHispaniola and the overall structure of the storm actually improved with expanding upper-leveloutflow and intense convection over the Barahona Peninsula. Continuing to move west-northwestward around the southern side of theBermuda High building westward over theSoutheastern U.S., Laura moved back over water in theWindward Passage and strengthened some before making landfall inEastern Cuba with 65 mph (105 km/h) winds and a 1000mbar (29.53inHg) pressure at 02:00 UTC on August 24. However, most of its convection was located south of the center due to wind shear.[1][16] Continuing to trek west-northwestward, Laura moved back over theCaribbean Sea just south of the coast of Cuba after being over land for six hours.[17] A period of dry air entertainment coupled with the continued effects of moderate northerly shear and land interaction briefly degraded and weakened the storm to 60 mph (97 km/h) as it struggled to remain organized throughout August 24 due to the lack of a defined inner-core with the most intense accompanying convection in a prominent band south of the circulation center.[18] However, this turned out to be short-lived as Laura reorganized and restrengthened over the warm waters of the Caribbean before making landfall on the western tip of Cuba inPinar del Rio province at around 00:00 UTC on August 25. At the time, it had 65 mph (105 km/h) winds and a 998 mbar (29.47 inch) pressure.[1][19]
After clearingCuba, Laura quickly began to gain more organization as it moved west-northwestward into the warm waters of theGulf of Mexico at a slightly slower speed.[1][20] The organization was accompanied by steady strengthening, and Laura was upgraded to a Category 1 hurricane at 12:15 UTC on August 25 after hurricane hunters found hurricane-force winds at the surface.[21] Laura then developed an inner core and acentral dense overcast (CDO), although it still had a somewhat ragged appearance on satellite imagery.[22] Its intensification continued to be slow due to the presence of some dry air and light northerly wind shear, but this eventually subsided, allowing Laura to become more organized and form a banding-type cloud-filledeye late on August 25 with its sustained winds reaching 85 mph (137 km/h) by 00:00 UTC on August 26.[23][1] With no more negative factors hindering strengthening andsea surface temperatures around 30 °C, Laura began torapidly intensify, becoming a Category 2 at 06:00 UTC before achieving Category 3 status just six hours later, making it the first major hurricane of the season. By this time, Laura was beginning to make a gradual northward turn in between the high-pressure ridge over theSoutheastern United States and a mid-level low nearOklahoma.[1][24]
As the day progressed, Laura's eye continued to clear out and the deep convection around it intensified and became more symmetric.[25] The satellite presentation continued to improve with the eye becoming better defined, and cloud tops colder than -70 °C in the surrounding ring of deep convection in the developingeyewall.[26] Laura continued to rapidly strengthen that afternoon and reached Category 4 intensity at 18:00 UTC.[27] The hurricane's eye reached a diameter of 30 mi (48 km) that evening and aircraft reconnaissance indicated it to have acquired sustained winds of 145 mph (233 km/h) by 21:00 UTC; this represented an increase of 65 mph (105 km/h) over a 24-hour period.[28] Laura's structure continued to improve with a very distinct, 25 nautical-mile-wide eye embedded in a symmetric central dense overcast and upper-level outflow becoming well established in all quadrants of the cyclone.[28] As it turned north-northwestward towards theLouisiana coastline, Laura reached its peak intensity at 00:00 UTC on August 27 as a high-end Category 4 hurricane with 1-minute sustained winds 150 mph (240 km/h) and a minimum central pressure of 937 mbar (hPa; 27.67 inHg), as measured by reconnaissance aircraft. At this point, the hurricane was located south ofLake Charles, Louisiana and south-southeast ofPort Arthur, Texas by a distance of 120 miles (190 km) each.[1][29]
Laura's rapid intensification then ended and its intensity more or less leveled off as it approached southwestern Louisiana.[1] Laura also began to experience some shear from the low to its west, which restricted its outflow on its west side and its pressure began to fluctuate.[30] However, Laura continued to have a very impressive appearance on satellite imagery with a well-defined eye and circular rain bands.[31] Turning almost due north, Laura made its final landfall nearCameron, Louisiana around 06:00 UTC with 150 mph (240 km/h) winds and a pressure of 939 mbars (27.73 inches).[32] The wind speed made Laura the first Category 4 hurricane to ever hit southwestern Louisiana since the1856 Last Island hurricane as well as the strongest hurricane to hit the state sinceHurricane Camille in1969 (which produced Category 5 conditions over the southeastern portion of the state).[1][33] Forecasters at the NHC described the system as "a ferocious looking hurricane with a clear circular eye, an intense eyewall, and tightly-coiled surrounding spiral bands."[34]
After landfall, Laura continued to move northward through the western side ofLouisiana. It passed just west ofLake Charles, Louisiana while still at Category 4 intensity with sustained winds at theLake Charles Regional Airport reaching 95 mph (153 km/h) with gusts up to 132 mph (212 km/h).[35] Despite this, Laura was already beginning to quickly weaken and its winds dropped to Category 3 intensity halfway betweenDe Quincy andOretta at 09:00 UTC before weakening to below major hurricane strength north ofSinger just an hour later.[36] Steadily turning more northeastward, Laura dropped to Category 1 status south ofNatchitoches, Louisiana at 14:00 UTC as its eye filled and its satellite and radar appearance degraded.[37] It weakened further to a tropical storm north ofArcadia at 17:00 UTC before moving intoSouthern Arkansas, where wind gusts in the state reached nearly 60 mph (97 km/h).[38] Convection around the storm center weakened further as the storm passed just east ofLittle Rock. Laura was downgraded to a tropical depression shortly after that at 03:00 UTC on August 28 and the responsibilities for issuing advisories on the storm was handed off to theWeather Prediction Center (WPC) since there was still a flood threat.[39][1]
Laura then accelerated as it turned northeastward and then east-northeastward as it began to lose tropical characteristics ahead of an approaching trough from the west. It moved throughSoutheastern Missouri and turned eastward intoKentucky before becoming a remnant low at 06:00 UTC on August 29. The WPC then issued its final advisory three hours later while the low was overHead of Grassy as the flood threat was generally over.[40][41] The low continued eastward throughWest Virginia andExtreme Northern Virginia intoMaryland before being absorbed by another low centered near theGreat Lakes by 12:00 UTC.[1][42]
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