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Hurricane Lorenzo (2019): Difference between revisions

Revision as of 15:58, 2 October 2019

Hurricane Lorenzo

Category 5 major hurricane (SSHWS/NWS)
Hurricane Lorenzo undergoing an eyewall replacement cycle on September 28
Formed	September 23, 2019 (2019-09-23)
Dissipated	Currenty active
(Extratropical after October 2)
Highest winds	1-minute sustained: 160 mph (260 km/h)
Lowest pressure	925 mbar (hPa); 27.32 inHg
Fatalities	3 total, 8 missing
Damage	Unknown
Areas affected	West Africa, Cape Verde, Azores
Part of the 2019 Atlantic hurricane season and 2019–20 European windstorm season

Hurricane Lorenzo, also known as Storm Lorenzo for the United Kingdom and Ireland while extratropical, was the easternmost Category 5 Atlantic hurricane on record.^[1] The twelfth named storm, fifth hurricane, third major hurricane and second Category 5 hurricane of the 2019 Atlantic hurricane season, Lorenzo developed from a tropical wave that moved off the west coast of Africa on September 22. On September 26, it rapidly intensified into a Category 4 hurricane before weakening due to an eyewall replacement cycle. After completing the cycle, Lorenzo rapidly re-strengthened, peaking at Category 5 intensity.

Meteorological history

On September 19, the National Hurricane Center (NHC) began to monitor a tropical wave that was forecast to emerge from the west coast of Africa.^[2] On September 22, the tropical wave emerged into the Atlantic Ocean.^[3] Under favorable conditions, the system quickly organized afterward, and at 03:00 UTC on the next day, the NHC initiated advisories on Tropical Depression Thirteen.^[4] Twelve hours later, the depression strengthened to a Tropical Storm and was named Lorenzo south of Cape Verde.^[5] Early on September 25, still under favorable conditions, the storm further intensified into a Category 1 hurricane.^[6] Several hours later, on the same day, Lorenzo further intensified into a Category 2 hurricane while initiating an eyewall replacement cycle, which hindered the development of the system somewhat.^[7] Early on September 26, the storm completed the cycle and underwent rapid intensification, reaching Category 4 status by 15:00 UTC that day. At this point, Lorenzo had become one of the largest and strongest hurricanes on record for the eastern Atlantic in the satellite era—the only comparable hurricane in recent times with similar size and intensity was Gabrielle in 1989.^[8] Lorenzo continued to intensify, reaching its initial peak intensity with maximum sustained winds of 145 mph (230 km/h) and a central pressure of 939 mbar (hPa; 27.73 inHg) early on September 27.^[9]

As Lorenzo began to turn slowly northward, the sea surface temperature dropped slightly and the hurricane weakened with the onset of another eyewall replacement cycle late on September 27.^[10] Though sea surface temperature remained at 28 °C (82 °F), strong wind shear continued to disrupt Lorenzo, causing the hurricane to bottom out as a low-end Category 3 storm on September 28.^[11] Although restrengthening was not forecast due to moderate wind shear and low ocean heat content, Lorenzo defied expectations and re-intensified to a Category 4 hurricane upon completing its eyewall replacement.^[12] Lorenzo continued to intensify, reaching Category 5 strength early on September 29,^[13] becoming the easternmost hurricane of such intensity recorded in the Atlantic basin, surpassing Hugo in 1989.^[14][1]

Lorenzo’s peak was short lived because of increasing wind shear, cooler waters and dry air; the hurricane lost its Category 5 status several hours later.^[15] This weakening trend became faster as it encountered increasingly hostile conditions. The hurricane's large size upwelled plenty of cool water, and Lorenzo dropped below major hurricane strength early on Septmeber 30.^[16] Early on October 2, Lorenzo passed just west of Flores Island, and weakened to a Category 1 storm.^[17] After passing the Azores, Lorenzo began an extratropical transition as the cloud pattern became increasingly asymmetric in appearance.^[18]

Preparations and impact

Bourbon Rhode

On September 27, the French ship Bourbon Rhode, with 14 crew members on board, issued a distress signal after sailing through Lorenzo. A NOAA Hurricane Hunter aircraft was diverted from the storm to assist in the search for the ship.^[19][20] On September 28, it was confirmed that the ship had sunk. Three crew members were rescued on a lifeboat, but the remaining 11 went missing.^[21] Three of the missing crew have been confirmed dead as of October 1.^[22][23]

Azores

Early on September 30, the Instituto Português do Mar e da Atmosfera (IPMA) issued hurricane and tropical storm watches for the Azores,^[24] which were upgraded to warnings later that day.^[25] Lorenzo began to bring tropical storm-force winds to Flores Island on October 1. Faial Island and Pico Island began receiving them 3 hours later.^[26] Flores started to be hit by hurricane force winds on the next day.^[27]

Ireland

Early on October 2, Irish Meteorological Service Met Éireann issued status orange wind warning for six west-most counties with winds expecting to reach mean speeds 65 to 80km/h with gusts generally of 100 to 130km/h, higher in coastal regions. The status orange valid from Thursday 3 October 2019 18:00 GMT to Friday 4 October 2019 03:00 GMT.^[28]

United Kingdom

While only arriving as an "ex-hurricane" in the United Kingdom and Ireland, the UK's Met Office said "very strong winds and heavy rain" were expected in western parts of Britain,^[29] and issued a weather warning for parts of Northern Ireland,^[30] as well as flood warnings for parts of England and Wales.^[31]

United States

Despite being over 2,000 mi (3,200 km) away from the storm, the National Weather ServiceinFlorida and North Carolina warned that the swells from Lorenzo could cause rip currents and beach erosion. People in coastal areas should stay away from the beach.^[32][33]

See also

• Other tropical cyclones named Lorenzo
• List of Category 5 Atlantic hurricanes
• Hurricane Gabrielle (1989) – another large and powerful hurricane in the central Atlantic Ocean
• Hurricane Hugo (1989) – the easternmost Category 5 Atlantic hurricane prior to Lorenzo
• Hurricane Karl (2004) – took a similar track in the open Atlantic

References

External links

Wikimedia Commons has media related to Hurricane Lorenzo (2019).

• The NHC's Advisory archive on Hurricane Lorenzo