Hurricane Isaias made landfall on the US Gulf Coast, bringing strong winds and dangerous flooding as a local official in Alabama urged preparedness despite his expectation that damage would not be severe.

The hurricane grounded flights but was expected to miss oil hubs. Wind and rain lashed the coast as the storm approached the Florida Panhandle, with flooding adding to the threat facing coastal communities.

On Dauphin Island, a barrier island off Alabama, Mayor Jeff Collier said he did not anticipate major damage. He nevertheless cautioned that a change in the hurricane’s course or a late increase in its strength could alter that outlook.

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Collier’s assessment combined a relatively reassuring expectation for the island with a warning against treating that expectation as certain. He urged readiness for a worse outcome, pointing to the possibility that even a small shift in the storm’s track could matter.

The outlook for oil hubs was similarly qualified: they were considered likely to escape the storm’s path, rather than certain to do so. With flights already disrupted, Collier’s warning underscored the distinction between expectations about the hurricane and the need to prepare for changes in its course or intensity.