Hurricane Florence Was the Nation's Second Wettest Storm Behind Harvey

An average of over 17.5 inches of rain fell as measured by five weather reporting stations covering 14,000 square miles from Fayetteville, North Carolina, to Florence, South Carolina, according to preliminary calculations from Dr. Ken Kunkel, a climate extremes researcher from North Carolina State University.

When analyzing a similar-size area, only Hurricane Harvey's 25.6 inches in August 2017 was wetter than Florence, dating to 1949, Kunkel found. The August 2016 Louisiana flood event came in third on Kunkel's list, meaning all three of the wettest storms have occurred within roughly two years' time.

Overall, Hurricane Harvey's deluge on southeastern Texas and far southwest Louisiana in 2017 was much greater than Florence's in the Carolinas.

(MORE: Florence Recap | Harvey Recap) 

Both storms drenched their respective regions for more than four days bringing massive flooding, but that's where their similarities end. 

The area drenched by more than 20 inches of rainfall covered more than three times more area in Texas and Louisiana during Harvey than in the Carolinas during Florence, according to an analysis by Dr. Shane Hubbard, a researcher from the Cooperative Institute for Meteorological Satellite Studies at the University of Wisconsin.

"They were two quite different storms and really not even comparable in terms of the amount of water that fell, " Hubbard said in an email to weather.com.

Two locations reported just over 60 inches of rain from Harvey, and five other stations reported totals that smashed the previous U.S. tropical cyclone rain record of 52 inches set in Hawaii during Hurricane Hiki in 1950.

Florence's peak total, while still prolific - just under 36 inches - was about 40 percent less than the peak total from Harvey.

(CLOSE UP: Harvey's Rainfall | Florence's Rainfall)

Another way of looking at the difference between the two storm's rainfall is to simply move Harvey's rainfall to the Carolinas. 

Hubbard's hypothetical analysis of Harvey's rain in the Carolinas shows how much more rain fell in Texas and how expansive Harvey's rainfall was. 

The total amount of water that fell during the two hurricanes is quite different: 33 trillion gallons in Harvey vs. 10 trillion gallons by some early estimates in the Carolinas from Florence. 

Both rainfall events are historic in their own right, with only a 0.1 percent chance of happening in any given year, or a 1,000-year rainfall event. Significant historic rainfall occurred over portions of southeastern North Carolina and a portion of northeastern South Carolina, according to Hubbard's analysis.  

The comparisons between storms are only that – for comparison's sake in history. Both hurricanes caused devastating flooding, but Harvey was a wetter storm overall from a scientific standpoint.