Kaua'i's 2018 Record-Setting Rain Caused by a Series of Supercell Thunderstorms
upstart writes:
Thunderstorms, not a cyclone, were the source of Kaua'i's 2018 record-setting rain:
A record-setting rainstorm over Kaua'i, Hawai'i in April 2018 resulted in severe flash flooding and estimated damage of nearly $180 million. The deluge damaged or destroyed 532 homes, and landslides left people along Kaua'i's north coast without access to their homes. Atmospheric scientists have now revealed that severe supercell thunderstorms were to blame.
The rainstorm inundated some areas with nearly 50 inches of rainfall in a 24-hour period, smashing the previous 24-hour U.S. rainfall record of 42 inches set in Texas in 1979. An interesting finding is that the rainstorm described in this paper was associated with a kona low and not a tropical cyclone as featured in previous U.S. rainfall records.
[...] "Updrafts with rotation are more intense and longer lived, and have been observed to produce large hail and tornados in Hawai'i," said Businger. "In this case, the updrafts were forced by Kaua'i's steep mountain cliffs, with the result that the thunderstorms were more vigorous and anchored to the terrain, thus setting a new US 24-hour rainfall record!"
[...] Although supercells thunderstorms are the least common type of thunderstorm in Hawaii, they have the greatest likelihood of producing severe weather, including large hail, tornados, and strong straight-line winds.
Journal Reference:
Terrence J. Corrigan, Steven Businger. The Anatomy of a Series of Cloud Bursts that Eclipsed the U.S. Rainfall Record, Monthly Weather Review, 2022,
DOI: 10.1175/MWR-D-21-0028.1
Read more of this story at SoylentNews.