President Trump on Friday declared a state of emergency in Florida as the state prepares for Hurricane Dorian.

The president ordered federal assistance to supplement state and local efforts responding to the hurricane, which is expected to strengthen into a potentially catastrophic Category 4 storm and slam into Florida’s eastern coast late Monday or early Tuesday.

Trump took the unusual step Thursday of canceling a weekend trip to Poland so he could stay in Washington to monitor the storm and “ensure that all resources of the federal government are focused on” confronting Dorian.

“It’s something very important for me to be here,” Trump told reporters in the Rose Garden. “The storm looks like it could be a very, very big one indeed.”

The White House said Trump’s emergency declaration authorizes the Department of Homeland Security and the Federal Emergency Management Agency to coordinate all disaster relief efforts.