On Friday, Hurricane Ida rapidly intensified. The storm went from a 30-kt Tropical Depression to a hurricane (35-kt) in 24 hours. This meets the NOAA definition of rapid intensification (RI). Of more concern, Ida is not even to the Gulf of Mexico where ocean temperatures and wind shear are very favorable for more strengthening. I am worried about this storm. The National Hurricane Center is using wording like “life-threatening” in recent weather discussions. Ironically, Hurricane Ida could make landfall on August 29th, which is the same date that Hurricane Katrina made landfall in 2005. Katrina was a catastrophic storm for the Gulf Region and New Orleans for a variety of reasons. Ida is a different storm, but I will be watching for the following small changes that could have big implications for that same region.
Will the storm have a second rapid intensification phase? This is a question that has haunted me all day. As I noted in a previous Forbes article, the Gulf of Mexico is significantly warm to support intensification, and there is a supportive wind shear environment. However, UCLA weather expert atmospheric scientist Daniel Swain astutely tweets, “50 – 100 mile jog to the right/east from the current ensemble mean track centerline would bring Ida right over the warmest part of the Loop Current (seea map above) and put highly populated SE LA (Louisiana) in the right front quadrant of a cat 4+…” At this time, it is not certain that Ida will strengthen to a Category 4 storm, but it is within the realm of possibility. I get his point.
Let’s break down a few of Swain’s points. The Loop Current is a current of warm water in the Gulf of Mexico that can often boost hurricane intensification. Scientists linked some of Hurricane Katrina’s intensification to traversing the Loop Current (map above). Ida, which is the fourth hurricane of the 2021 season, will intensify whether it moves over the Loop Current or not, but this is something worth watching in the coming days.
Swain’s point about the right front quadrant is also worth a deeper explanation. As horrific as Katrina was, it could have been “meteorologically-worse.” The eastern eyewall and right front quadrant of Katrina was east of New Orleans and impacted much of the Mississippi Gulf Coast. Let me stop right here and emphasize that the lives and property of less populated regions than New Orleans are equally important so don’t miss the overall point being made. I am very sensitive to the “urban” bias that is quite prevalent in coverage and warning of extreme weather events.
The map above shows one potential landfall scenario from the H-WRF model. While this is subject to change, this landfall location would place many parishes and the city of New Orleans on the right side of the eye. Historically, the right front quadrant is where the strongest winds are because of the addition of the movement of the storm with the counter-clockwise circulating winds. The storm surge and tornado threat are also greatest in that quadrant. To Swain’s point, this position or even a nudge eastward increases the exposure of New Orleans to some of the strongest winds, rainfall, and surge.
Another facet of the storm that I will be watching for is the angle of approach. New Orleans is a low-lying city with the Gulf of Mexico to its south and Lake Ponchetrain to its north. A hurricane approaching from the southeast to the northwest would bring “worst-case scenario” surge to the region.
Officials seem to have gotten the notice. As of Friday afternoon, I have seen the following notices (and many others are likely to come):
- Mandatory evacuations in Louisiana Parishes and New Orleans for areas with limited levee protection. Voluntary evacuations are also in effect.
- New Orleans Public Schools and Central Offices will be closed on Monday, August 30th.
I am worried about this one y’all.
FOLLOW US ON GOOGLE NEWS
Read original article here
The post Small Changes In Hurricane Ida Could Bring Big Risks For New Orleans And The Gulf Coast appeared first on Gamers Grade.