"We've got about twice the normal number of vessels waiting," the Coast Guard spokesman said.
A total of 32 vessels inbound and 34 outbound were waiting to enter or leave Houston, Galveston and Texas City, all served by the 53-mile (85-km) Houston Ship Channel through Galveston Bay, the spokesman said.
Most of the traffic into and out of the area involves oil and petroleum products tankers with a significant number of container and grain ships in the mix.
Fog is a seasonal problem in winter along the Texas Gulf Coast. A weather front pushed through the area, causing visibility and operational problems for vessels transiting the bay. (Reuters)