Oct 12, 2016

Hurricane Matthew Brought 1000-Year Record Rainstorms to North Carolina

Fayetteville, NC
Elizabethtown, NC
William O Huske Lock and Dam Number 3, White Oak, NC
Elena Gooray
Pacific Standard

The storm swept in by Hurricane Matthew has produced rainfall that exceeds the level expected about once every 1,000 years, according to a statistical analysis using National Oceanic and Atmospheric Administration data.

...The flood was also likely made worse by climate change. The 14 inches that accumulated in Fayetteville on Saturday is more than 90 percent likely to fall outside the town’s 1,000-year rainfall return period for a 24-hour rainstorm, and it more than doubled the previous single-day record of 6.80 inches from 1999’s Hurricane Floyd. In fact, only four whole months in Fayetteville’s recorded weather history have seen over 14 inches of total rainfall, Weather Underground has reported. At least two other spots in North Carolina broke the 90 percent confidence intervals for 1,000-year storms: Elizabethtown, with a reported 18.38 inches, and William O. Huske Lock, with 15.65.

Matthew has extended a growing trend of minimum-500-year rainfall events across America, as Eric Holthaus reported for Pacific Standard in August, following Louisiana’s historic storm:

Today’s rainstorm in Louisiana is at least the eighth 500-year rainfall event across America in little more than a year, including similarly extreme downpours in Oklahoma last May, central Texas (twice: last May and last October), South Carolina last October, northern Louisiana this March, West Virginia in June, and Maryland last month

“Matthew no doubt rained more than an identical storm would have 30 or 40 years ago because it is warmer,” Kerry Emmanuel, a meteorologist at the Massachusetts Institute of Technology, told the Associated Press.