The email landed in the inbox of Dave Parker, an Arkansas government employee, in 2021: Hey, we’ve got this eclipse coming.

“I wasn’t even aware of an eclipse coming in ’24,” Mr. Parker said.

But after the first meeting, the headlines became clear: “This could be possibly the biggest economic moment for Arkansas ever,” said Mr. Parker, who became the point eclipse spokesman for the state’s Transportation Department.

For more than two years, he and others in state and local governments have been bracing for a flood of tourists. Much of Arkansas is in the path of totality, meaning those areas will be plunged into darkness for about four minutes.

“Many people will be coming to our state for the first time,” Gov. Sarah Huckabee Sanders said at a news conference last month, “and we want to make sure they keep coming back.”

Vendors with eclipse-themed merchandise in Russellville, Ark., on Sunday.Alex Kent for The New York Times
Eclipse-themed merchandise leading up to the solar event in Russellville.Alex Kent for The New York Times

Arkansas has miles of rugged terrain and an array of state parks, but it does not have a major professional sports team. Officials have struggled to think of an event comparable to the April 8 eclipse. The 2004 opening of the Clinton presidential library in Little Rock? That attracted around 30,000 people. A football game at the University of Arkansas? That has topped out at about 76,000 fans.

The state is forecasting that the eclipse may attract as many as 1.5 million tourists to Arkansas, as well as hundreds of thousands of the state’s residents driving to get to a better viewing spot.

“We really don’t know what to expect,” said Ellen Coulter, a spokeswoman for the Transportation Department. “So we’re just trying to overprepare as much as possible.”

Several schools will be closed. There is a special traffic plan, crafted in part by looking at where hotels are booked and where people are expected to drive in. Several state parks are ready for an influx of guests.

For the state Emergency Management Division, planning for the eclipse was like gearing up for severe weather or a natural disaster.

Attending an eclipse-themed event in Russellville.Alex Kent for The New York Times
Gathering outside an American legion on Sunday, before the eclipse in Russellville.Alex Kent for The New York Times

The biggest surprise, said A.J. Gary, the division’s director, was that “there are that many people that are planning to come into the state to view it.”

His department and others reached out to South Dakota, Missouri and other states that were in the path of totality during the 2017 eclipse to review how they handled the influx.

On Monday, several officials plan to be downtown at their headquarters in Little Rock, the state capital, to monitor traffic and keep the public updated.

But everyone will take a few minutes around 1:51 p.m. Central time to step outside, glasses in hand, and take in the eclipse.

“After all this planning,” Ms. Coulter said, “we’re going to look at it.”