Did hurricanes Katrina, Gustav, Issac, Harvey and Ida all make landfall on the same day of the calendar? No, that's not true: While they made landfall within a few calendar days of each other in different years, they did not all make landfall on the same day. A scientist in the Department of Atmospheric Science at Colorado State University said that only three of the hurricanes listed share landfall on the same date, and this is because "highly impactful storms typically occur in late August and early September since that's when the Atlantic hurricane season tends to be at its busiest."
The claim appeared in a Facebook post (archived here) on August 30, 2021. The caption opened:
Interesting...
The text in the meme reads:
Katrina 8/29/2005
Gustav 8/29/2008
Issac 8/29/2012
Harvey 8/29/2017
Ida 8/29/2021
This is what the Facebook post looked like on August 31, 2021:
(Source: Facebook screenshot taken on Tue Aug 31 22:23:20 2021 UTC)
Lead Stories reached out to Colorado State Research Scientist Phil Klotzbach via email regarding this claim. Concerning the dates Hurricane Katrina, Hurricane Gustav, Hurricane Issac, Hurricane Harvey and Hurricane Ida made landfall, Klotzbach said:
the dates of these storms actual landfalls are as follows (dates are listed in Greenwich Mean Time, not local time):
Katrina: 8/29/2005
Gustav: 9/1/2008
Isaac: 8/29/2012
Harvey: 8/26/2017
Ida: 8/29/2021
Although these hurricanes did hit within a seven-day window on the calendar, they did not all make landfall on the same day and none hit in the same year. Klotzbach said there's a scientific explanation for the timing:
While Atlantic hurricane seasons runs from June 1 - November 30, the peak of the Atlantic hurricane season occurs between August-October, with over 60% of all Atlantic hurricanes forming between August 20 - October 10.
Consequently, it's not a surprise that highly impactful storms typically occur in late August and early September since that's when the Atlantic hurricane season tends to be at its busiest. And also, while Gustav and Isaac were damaging storms, they certainly weren't in the same league in the damage department as Katrina, Harvey and Ida!
