All eyes have been on Tropical Storm Isaac soon to be Hurricane Isaac this weekend. This storm has been interesting to watch from a forecasting prospective. Late last week many computer models were showing a variety of tracks. Some had Isaac heading into the Gulf of Mexico while others had it veering right and moving into the Atlantic. Now the models have a better idea of where it’s going to go. The track doesn’t look good for the states along the gulf – and to make matters worse it’s going to hit the exact same day Katrina hit New Orleans seven years later.
While Isaac isn’t as strong as Katrina, both storm paths are eerily similar. I thought I would take a look back at Katrina - a storm many of us will never forget.
Katrina formed near the Bahama’s on August 23, 2005 as a tropical depression.
Satellite Image: NOAA
The storm quickly strengthened to a category one hurricane and made its first of two landfalls on August 25th near North Miami Beach, Florida.
The storm only spent seven hours over Florida and intensified once it hit the warm waters in the Gulf of Mexico. Sea surface temperatures were one to two degrees above normal and the warmer water wasn’t just at the surface. The was a large depth of water that was warmer back in 2005. There was also little to no vertical wind sheer which means the thunderstorm tops weren’t ripped apart. These are the perfect conditions for a hurricane to thrive. Katrina fed off of these factors and by August 26th hit “major” status which is a category three storm or higher.
Katrina as a category 5 storm; Image from NOAA
By August 28th it reached category five strength with winds near 170mph. The eye of the storm was well defined, waves were high and so were the winds. It was on track to hit the gulf coast and no one knew it would cause so much destruction.
On August 29, 2005 Katrina made it’s second and most damaging landfall. It weakened to a category three storm as it hit Grand Isle, Louisiana but it still was a strong storm. Winds topped out at 125 mph and the central pressure dropped to 920millibars which is the third lowest on record for a land falling Atlantic storm. Rain fell at one inch per hour in some locations and the storm surges were 10-19 feet in Louisiana, 24-28 feet in Mississippi.
Here’s a link to a radar animation as Katrina was making landfall in Louisiana.
Rainfall and wind gusts; Image from NOAA
Now Isaac is a different storm even though it’s going to make landfall on the same day almost in the exact same place. Isaac formed east of the Leeward Islands and brought Haiti and Cuba heavy rain. The storm was disorganized due to the mountainous terrain from both countries however once over the open gulf Isaac started to organize a little more. There was no direct landfall in Florida from Isaac but rain bands hit the state hard producing heavy rain and tornadoes.
Isaac is not expected to be as strong as Katrina but that may not matter. The storm is moving slowly and will likely produce heavy amounts of rain near New Orleans. Here’s a look at one of our computer model’s rainfall forecast.
The worst part of a hurricane is near the right front quadrant – the rain is heavier here and the winds are stronger. That’s because not only do you get the wind from the rotation of the storm but also the forward motion of the storm. The right front quadrant is where the strongest winds occur and those are heading right for Louisiana.
Here’s the path updated Monday morning:
Eerily similar…however Katrina spent a little more time in the warmer waters of the Gulf while Isaac is taking a more westerly track.
I have read many reports saying that Louisiana and New Orleans have learned from Katrina and have plans in place. I am happy to hear this and I hope we don’t see a repeat of seven years ago.
If you want to track Isaac’s path we have set up a great feature on our website. Click HERE to find out where Isaac is and the latest forecast. We have also set up a photo gallery of Isaac images. Click HERE to view the photo gallery.