Many of the toppled containers were empty, Cooper/Ports America general manager Alex Montoya said, but some full containers were also overturned.
According to Lt. John Krueger with the La Porte Police Department, there were two injuries reported at the port, but it was not immediately clear where in the terminal or how the two injuries occurred. He added that no tornadoes appear to have touched down in La Porte.
Employees at the scene said the heavy winds also moved a modular trailer across the parking lot.
PHOTOS: Storm damage across southeast Texas
"Containers were falling over, buildings were moving, trucks were being flipped upside down -- it was just really scary," recalled one employee.
VIDEO: Witnesses recount severe weather at Ship Channel
"It just got bad and dark really quick," another employee said.
Heavy winds ripped several large pieces off the roof of the Best Transportation facility near the Pasadena-La Porte border, carrying the debris into a neighboring field. Several cars and an 18-wheeler were also overturned in the building's parking lot.
VIDEO: Wind damage to Best Transportation facility in Pasadena
Although property managers are still completing a damage assessment, they said nobody was injured within the building.
A Pasadena ISD bus stalled in street flooding near Almeda and the Gulf Freeway. Students on their way home from school are on the bus, according to a Pasadena ISD spokesperson, and waiting for another bus to reach them to take them home.
Heavy street flooding also occurred in several parking lots and other areas off of the Gulf Freeway, but the freeway itself and its feeder roads remained largely dry.
Near the intersection of I-45 and Beltway 8, a pastor and staff at Sagemont Church sprung into action as floodwaters rose around a woman and her two children parked in a car on the median.
The rescuers waded through waist-deep water to rescue the family.
"We want to be living proof of a loving God to a watching world, so we saw people in need and we couldn't help ourselves but to give them some assistance," said junior high minister Matt Armendarez.
In Pearland, rising floodwaters threatened several homes in low-lying areas.
"Once it started coming up, it kept coming. Even after the rain stopped, it still rose," said one homeowner as he stood in several inches of water in his living room. "Most of the water that's in the house came in after it started raining."
A Flash Flood Warning has been issued for Liberty and Chambers counties until 7 p.m.
In addition, a Tornado Watch is in effect until 9 p.m. for portions of southeast Texas and western Louisiana, but not including Houston.
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