Gulf of Mexico disturbance creating dangerous floods and tornadoes

The tropical disturbance (92L) that formed over the Gulf of Mexico this weekend has moved inland over Texas. The storm is affecting Texas, Louisiana, and Mississippi much like a tropical storm would. An upper-level trough of low pressure is interacting with 92L and bringing very heavy rains, flooding, and tornadoes. The Houston NWS weather discussion from this morning calls this a "very dangerous heavy rain event". Four to six inches of rain have already fallen over some coastal regions, with another 3-5 inches expected today. With high winds and high tides over the Gulf, draining of rivers along the coast is being hampered, adding to the flooding problems. The disturbance is generating sustained winds of tropical storm force over the Gulf of Mexico. Buoy 42362 off the coast of Louisiana has seen sustained winds of 45 mph with higher gusts this morning. Numerous waterspouts and tornadoes have been spawned in some of the heavier thunderstorms. At 3am this morning, a tornado ripped into a boat yard in Leeville, LA, hurling boats around, flipping two mobile homes, and injuring four people. Tornadoes have also been reported in Lumberton, China, and Magnolia Beach in Texas this morning, with some damage reported. Radar in Lake Charles, LA is showing numerous severe thunderstorms with possible tornadoes this morning. Heavy rains in coastal Mississippi triggered floods this morning in Waveland, forcing evacuations in that city, which was mostly destroyed by Hurricane Katrina.


Figure 1. Total estimated rainfall from 92L measured by the Houston radar.

Elsewhere in the tropics
The tropical disturbance just north of Puerto Rico (90L) is under 20 knots of wind shear, and should get torn apart by Tuesday. The disturbance will bring heavy thunderstorm activity to portions of Puerto Rico today. We'll have to watch the Gulf of Mexico this week, as shear is expected to remain low and more disturbances like 92L may develop.

I'll be back with an update Tuesday morning.

Jeff Masters