Sunday, June 21, 2020

Hurricane history snapshot may hold surprises

Aftermath of Superstorm Sandy,
near Breezy Point, NY










By Jane Feehan

The North Atlantic hurricane season begins June 1 and ends Nov. 30. Always cause for speculation by the media, government, and the public, hurricanes are the topic of discussion for six months a year. 

Many tend to contrast and compare seasons in their life time, but weather history (and climatological history) has a backdrop of many decades and centuries.

Official hurricane tracking, however, spans a comparatively short time though an early printed weather map showed a hurricane off the U.S. coast between Jacksonville and Savannah Sept. 28, 1874. 

Early reporting came via oral accounts of local conditions. Decades later, ship radios played a key role in transmitting storm conditions and information from sea. Aircraft reconnaisance began in the mid 1940s. The first satellite for hurricane observation was deployed for the 1967 season.

Statistics for damage costs go up each decade, in part because more people live on coastlines and construction costs may rise each decade, if not year.

1. Hurricane deaths: most then, as now, die of drowning.

Most deaths:
Great Hurricane, mid-October 1780 in the Lesser Antilles: 22,000
9,000 died in Martinique
4,000-5,000 in St. Eustatius
4,326- Barbados
Thousands off shore

Also before the 20th century (and there were several, but stats not official):
Cheniere Caminada Hurricane, 1893, also known as Great October Storm
770 died in Louisiana
An estimated 2,000 died in Mississippi

Most US deaths 20th century:
Galveston Hurricane, Aug 27, 1900: official number is “at least” 8,000 with s
ome estimates at 12,000

Second Deadliest in US 20th century:

Hurricane of 1928 or Okeechobee hurricane
2,500 deaths - official count as of 2003. Unofficially, the number exceeds 3,000. Bones of human remains continue to be recovered in rural areas.

Three others-not US- most deaths attributed to:

Aug. 25, 1930-Dominican Republic - about 8,000 died
Oct. 2, 1963-Flora in Haiti and Cuba - about 7,000 deaths
Sept. 18, 1974-Fifi in Honduras - between 3,000 and 10,000 deaths 

2. Forecasting Errors. There are many variables in forecast accuracy but there seems to be a correlation in: 

Years dominated by hurricanes or tropical storms that move through the low latitude easterly trade winds typically hold the lowest number of forecast errors.

Years in which hurricanes or tropical storms move through the mid-latitude westerlies (as during El Nino years) hold the largest number of errors.

3. Worst decades for Florida hurricanes:

1940-49: 10 hurricanes
1920-29:   8
1960-69:   8
2000-09:   7
2010-19:   3 and several near misses and tropical storms. Irma in 2017, Cat 5 Michael in 2018. 

Hurricane Ian of 2022, a Cat 5, was the deadliest hurricane to hit Florida since the 1935 storm, with a 161 deaths. 

4. Number of hurricanes to strike mainland U.S. each decade. A report is not yet published for the post 2004 decade. "Most-ever" assessments of all Atlantic tropical storms when basin activity couldn't be widely observed and measured accurately until the satellite era are questionable. Since 2000, another metric--Accumulated Cyclone Energy (ACE)--is also reported. This metric was developed by William Gray and his associates at Colorado State University during the 1990s. 

U.S. hurricane strikes by decade:
         




Years since 2004
Below are highlights only, not complete analyses, of Atlantic hurricane season summaries produced by the National Hurricane Center and Statista. Numbers change at times depending on new data, thus a delay in complete reporting.

2005
There were 28 named storms, 15 hurricanes, seven major and four hit the US. Since reliable records began around the middle of the 20th century (1944) only one season had exceeded 20 named (no names then but classified) storms before 1944 and that was 1933.

2012 
Two destructive hurricanes hit the US: Sandy and Isaac.
 The season ranks "above nornal, but not exceptionally so."

2017
Three major hurricanes struck the US in 2017: Harvey, Irma and Maria

2018
Two hurricanes, Florence and Michael made U.S. landfall (and two of tropical-storm strength) in 2018. That year, the North Atlantic hurricane season saw 15 named storms, 8 hurricanes, and two major hurricanes. This is above the 1981-2010 average of 12.1 named storms, 6.4 hurricanes, and 2.7 major hurricanes. The number of named storms ranked as a tie for the tenth most on record. 

2020
The North Atlantic had 30 named storms, which broke the previous record of 28 in 2005. Of those 30 storms, 13 were hurricanes, six of which were major hurricanes that struck the U.S. Both these totals are the second highest on record behind 2005.

2021
Two major hurricanes hit the U.S. in 2021. Eight tropical cyclones, including the two major hurricanes, made landfall in the contiguous U.S. in 2021, down from eleven in 2020.

2022 
Three major hurricanes struck the U.S. mainland in 2022. The North Atlantic hurricane activity was near its 1991-2020 average. Near normal but below basin activity slightly below average.

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Sources:
National Hurricane Center:
https://www.nhc.noaa.gov/pastdec.shtml