Around August 23, a tropical wave that had entered the Atlantic basin back in mid-August began to generate some concentrated thunderstorm activity as it crossed into the Caribbean Sea. Most of the vorticity associated with the system was quite far south, though, and still embedded in the intertropical convergence zone. On the 25th, a broad low formed along the wave axis. In part due to the influence of an upper-level trough over the northwest Caribbean, the system consolidated farther north, culminating in Tropical Depression Nine the next day. At that point, it was located just southwest of Jamiaca and was lifting to the north-northwest.
Initially, most of the rain was displaced north and east of the low-level circulation, causing considerable flooding in Jamaica. The storm was over very warm water and in an environment of high relative humidity, though, so it wasted no time in organizing. By that afternoon, it was upgraded to Tropical Storm Ida. Overnight, vigorous convection began a trend of rapid intensification, which continued through August 27. By the time its center was baring down on western Cuba that afternoon, Ida was already a hurricane. The system first crossed over Isla de la Juventud, before making landfall in mainland Cuba that evening as a category 1. Land interaction barely slowed down the storm, and before long it had continued northwest into the Gulf of Mexico.
Conditions in the Gulf were nearly ideal: wind shear died down even more, the atmosphere was moist, and Ida's path took it directly over a warm eddy that had some of the highest oceanic heat content in the Atlantic basin. Intensification was at first slow and steady as the cyclone cleared out an eye on the 28th and became a category 2 hurricane. During the final day of its approach to the Gulf coast, however, Ida exploded. The minimum central pressure was observed to drop from 985 mb to 929 mb in just 24 hours, bringing the hurricane to category 4 strength with top sustained winds of 150 mph. The storm had also grown significantly and carried an enormous storm surge into southeast Louisiana upon landfall during the early afternoon of August 29. These top winds matched those of Laura a year earlier, tying the record for the highest recorded in a Louisiana landfall.
The storm brought hurricane-force winds well inland as it turned north and weakened. Early on August 30, it was downgraded to a tropical storm and crossed into Mississippi. It became a tropical depression and turned northeastward that evening. Even after bringing 10+ inches of rain to a large swath of Louisiana and Mississippi, Ida caused more tremendous rainfall on its journey toward the Atlantic. An interaction between it and an approaching cold front led to the cyclone's post-tropical transition on September 1, but more importantly led to enhanced precipitation over parts of the mid-Atlantic and widespread flooding. The next day, Ida's remnants moved over Atlantic Canada before dissipating.
The above image shows Ida at peak intensity as a strong category 4 hurricane just before landfall in Louisiana.
Ida's track took it directly across areas of high oceanic heat content in the northern Gulf of Mexico; this contributed to the rapid intensification just before landfall.
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