Projections for the Number of Future Severe Rain Events Likely to Increase

Louisiana will likely see an increase in projections for the number of expected severe rain events going forward.

The increase is likely to be a part of an update to NOAA’s Atlas 14 rainfall frequency forecast. State Climatologist Barry Keim said over the last ten years it appears that we are getting more frequent, powerful rainstorms that drop water faster than they did previously.

“We’re not so much talking about annual rainfall but what this is really drilling down on is those extreme storms and the analysis is done on the biggest storms that occur,” said Keim who notes the August 2016 Flood alone will account for a big part of the forecasted increase. “No doubt that one storm event across about a quarter of Louisiana with horrific rainfall totals would absolutely have an impact on what those precipitation frequency totals would look like.”

Atlas 14 creates projected rain totals over the next year, ten years, hundred years, and further out then predicts the projected rainfall in major events down to the minute. Keim says the Great Flood of 2016 is likely to play a large increase in those potentially increased forecasts due to its widespread and historic impact.

Keim said if we are getting more frequent storms capable of flooding then this certainly will have an impact on your flood insurance rates and the cost of building increasingly flood-resistant government infrastructure.

“Obviously if we are getting more storms dumped in shorter periods of time and things like that it puts all of the infrastructure under more stress,” said Keim. “We need better drainage networks to be able to cope with that and that is not an easy thing to do quickly, and it is very expensive on top of that.”