|Category 4 major hurricane (SSHWS/NWS)|
|Formed||June 28, 2020|
|Dissipated||July 23, 2020|
|(Remnant low after July 20)|
|Duration||3 weeks and 1 day|
|Highest winds||1-minute sustained: |
140 mph (220 km/h)
|Lowest pressure||938 mbar (hPa); 27.7 inHg|
|Fatalities||68 direct, 7 indirect|
|Damage||$11.72 billion (2020 USD)|
|Areas affected||Southeastern United States, New England, Lesser Antilles, Canada, Puerto Rico, Bahamas|
|Part of the 2020 Atlantic hurricane season|
Hurricane Bertha was the 3rd longest-lasting hurricane in the Atlantic Basin on record, lasting for a total of 25 days as a tropical cyclone, only behind Hurricane Ginger and the San Ciriaco Hurricane. It was a devastating Category 4 hurricane that struck the state of North Carolina, causing severe flooding and wind gusts in that area. The second storm, first hurricane, and first major hurricane of the 2020 Atlantic hurricane season, the origins of Bertha trace back to a tropical wave, that emerged off of Africa on June 20.
A tropical wave emerged off the coast of Africa on June 20, slowly drifting west while gradually organizing over warm waters. On June 24, it was finally recognized by the NHC and on June 26 at 18:00 UTC, it was upgraded to Potential Cyclone Two, the NHC giving it a 90% chance of forming in the next 48 hours. It had tropical storm strength six hours later and at 00:00 UTC on June 28, it was finally a tropical storm, the NHC naming it Bertha. It then intensified a little quickly and on June 30 at 06:00 UTC, it was upgraded to a hurricane and exactly one day later, strengthened into a Category 2 hurricane. It reached its first initial peak intensity on July 1 at 12:00 UTC, with 100 mph (160 km/h) winds and a pressure of 978 mbar.
Due to it moving into a small area of wind shear, it abated slightly gradually, falling back to a Category 1 on July 2 06:00 UTC and then a tropical storm the next day, as it made a small loop around. Once it fully completed its loop, it exited the area of wind shear, and started gradually intensifying again. On July 4 at 12:00 UTC, it intensified back into a Category 1 hurricane and 18 hours later, strengthened into a Category 2. On July 7 at 12:00 UTC, it further intensified into a major hurricane, reaching its second initial peak intensity another 18 hours later, with winds up to 120 mph (190 km/h) and a minimum pressure of 960 mbar.
During the period of July 8, 18:00 UTC to July 9, 12:00 UTC, Bertha then impacted some islands in the Lesser Antilles, hitting the islands of Barbuda, Saint Barthélemy, Saint Martin/Sint Maarten, and Anguilla respectively. At the same time, it also underwent an eyewall replacement cycle, causing it to start weakening. It fell below major hurricane strength on July 9, 12:00 UTC and weakened to a Category 1 24 hours later. It took a turn to the north and then further diminished into a tropical storm on July 11 at 12:00 UTC, where it held that strength for 12 hours before intensifying back into a hurricane. That same time, it then took a sharp turn to the west. On July 12 at 18:00 UTC, the hurricane unexpectedly rapidly intensified, reaching major hurricane strength on July 14, 06:00 UTC and then a Category 4 12 hours later. It reached its peak intensity on July 15, 06:00 UTC, with maximum winds of 140 mph (220 km/h) and a minimum central pressure of 938 mbar (hPa).
|Longest duration Atlantic tropical cyclones|
|1||"San Ciriaco"¶||1899||28 days|
|Sources: HURDAT, Atlantic hurricane best track, HRD, NHC|
|¶ Fluctuated between tropical and post-tropical|
during its existence, so the number of days
After that, it began another eyewall replacement cycle, again diminishing the hurricane as it approached the Carolinas. It weakened to a Category 3 on July 16, 06:00 UTC and then fell below major hurricane on July 17, 12:00 UTC. Bertha made its landfall in southern North Carolina on July 18 at 00:00 UTC. It quickly abated over land, weakening to a tropical storm on July 19, 00:00 UTC and then to a tropical depression 12 hours later. It then became a remnant low on July 20, reaching Canada quickly as it attained tropical storm force winds.
The southern United States planned ahead for the hurricane, closing 300,000 businesses and schools there. The Carolinas held a state of emergency in case the states were devastated by the hurricane. Those state ordered a mass evacuation for the areas that are in/near the coast, with 900,000 people evacuating. Those people in these two states got their supplies and they evacuated or stayed behind for the hurricane to come.
- ↑ Neal Dorst (January 26, 2010). "Subject: E6) Which tropical cyclone lasted the longest?". Hurricane Research Division. National Oceanic and Atmospheric Administration. Archived from the original on September 24, 2008. https://web.archive.org/web/20080924074803/http://www.aoml.noaa.gov/hrd/tcfaq/E6.html. Retrieved October 3, 2012.
- ↑ Lixion Avila & Robbie Berg (October 4, 2012). "Remnants of Nadine Discussion Eighty-Eight (Final)". National Hurricane Center. National Oceanic and Atmospheric Administration. http://www.nhc.noaa.gov/archive/2012/al14/al142012.discus.088.shtml?. Retrieved October 4, 2012.