The big picture: Ida intensified at an astonishing rate early Sunday, leaping from a 105 mph Category 2 storm at 11 p.m. ET Saturday to the cusp of Category 5 intensity as it spun closer to the southeastern coast of Louisiana.
Threat level: The storm is bringing a peak storm surge (water inundation above normally dry ground) of between 12 to 16 feet to south coastal Louisiana, between Port Fourchon and the Mouth of the Mississippi River.
- The Hurricane Center is calling the surge "extremely life-threatening" particularly within the region from Burns Point, Louisiana, to Ocean Springs, Mississippi.
- Lower amounts of surge are expected closer to New Orleans, and the city's Hurricane Risk Reduction System is designed to protect the city from a storm surge of this magnitude.
- In New Orleans, 15 to 20 inches of rainfall or more could fall, overwhelming the city's pumping system and causing extensive flash flooding, the National Weather Service warns.
- Water levels were already rising quickly along the coast on Sunday morning, a few hours before landfall.
Details: Where the core of the storm comes ashore, "catastrophic" wind damage is expected, the National Hurricane Center warns, with 175 to 180 mph wind gusts near the shore, and extremely dangerous winds spreading inland throughout the day.
- "Treat these imminent extreme winds as if a tornado was approaching and move immediately to an interior room or shelter," the Weather Service forecast office in New Orleans advises.
- New Orleans and Baton Rouge are likely to see winds exceeding 100 miles per hour, with widespread power outages almost certain, and some structural damage possible. If the core of the storm hits New Orleans, winds could gust to Category 2 or 3 intensity for a time, greatly exceeding those seen in recent hurricanes there.
- Numerous oil and gas facilities and chemical plants are in the path of some of the strongest winds and storm surge, including the strategic Port Fourchon, which is integral to the Gulf of Mexico's oil and gas production.
- Damage to infrastructure there and upriver, between New Orleans and Baton Rouge, could lead to environmental hazards and delays in resuming oil and gas production in the Gulf.
Context: The rapid intensification, which exceeded forecasts, was due to extremely warm ocean waters and ideal conditions in the atmosphere as well. The Gulf of Mexico served as gasoline thrown onto the fire of the storm.
- Climate change, by warming air and ocean temperatures, is leading to both stronger and wetter hurricanes, and also more storms that rapidly intensify.
- The Gulf of Mexico has seen a recent trend of storms like Ida, which strengthen right up through landfall.
