Now playing
01:10
Hurricane warning in effect along Gulf Coast
Larry Pierson, from the Isle of Palms, S.C., purchases bottled water from the Harris Teeter grocery store on the Isle of Palms in preparation for Hurricane Florence at the Isle of Palms S.C., Monday, Sept. 10, 2018. (AP Photo/Mic Smith)
Larry Pierson, from the Isle of Palms, S.C., purchases bottled water from the Harris Teeter grocery store on the Isle of Palms in preparation for Hurricane Florence at the Isle of Palms S.C., Monday, Sept. 10, 2018. (AP Photo/Mic Smith)
PHOTO: Mic Smith/AP
Now playing
00:57
How to prepare for a hurricane
IN SPACE - In this handout photo provided by NASA, Hurricane Patricia is seen from the International Space Station. The hurricane made landfall on the Pacfic coast of Mexico on October 23. (Photo by Scott Kelly/NASA via Getty Images)
IN SPACE - In this handout photo provided by NASA, Hurricane Patricia is seen from the International Space Station. The hurricane made landfall on the Pacfic coast of Mexico on October 23. (Photo by Scott Kelly/NASA via Getty Images)
PHOTO: NASA
Now playing
01:07
Why hurricanes are so hard to predict
PHOTO: Courtesy Amy Lloyd
Now playing
01:06
Why flash floods are so dangerous
Now playing
01:26
Hurricanes: What you don't know
LAS VEGAS, NV - JULY 07:  Lightning strikes during a thunderstorm on July 7, 2015 in Las Vegas, Nevada. The monsoon storm dropped heavy rain and hail in parts of the valley causing street flooding and power outages.  (Photo by Ethan Miller/Getty Images)
LAS VEGAS, NV - JULY 07: Lightning strikes during a thunderstorm on July 7, 2015 in Las Vegas, Nevada. The monsoon storm dropped heavy rain and hail in parts of the valley causing street flooding and power outages. (Photo by Ethan Miller/Getty Images)
PHOTO: Ethan Miller/Getty Images North America/Getty Images
Now playing
01:36
How to protect yourself from lightning
how hurricanes are named orig_00002729.jpg
how hurricanes are named orig_00002729.jpg
Now playing
01:38
How are hurricanes named?
Now playing
01:21
What is a polar vortex?
PHOTO: Franck Verdière/Twitter
Now playing
01:10
What 'rapid intensification' means for storms
A plea for help on a New Orleans rooftop, days after Hurricane Katrina struck the city in 2005.
A plea for help on a New Orleans rooftop, days after Hurricane Katrina struck the city in 2005.
PHOTO: AFP/Getty Images
Now playing
02:14
Top five costliest hurricanes in US history
Storm chasing photographers take photos underneath a rotating supercell storm system in Maxwell, Nebraska on September 3, 2016. Although multiple tornado warnings were issued throughout the area, no funnel cloud touched down. / AFP / Josh Edelson / XGTY
RESTRICTED TO EDITORIAL USE  / MANDATORY CREDIT:  "AFP PHOTO / Josh EDELSON" / NO MARKETING / NO ADVERTISING CAMPAIGNS /  DISTRIBUTED AS A SERVICE TO CLIENTS  ==        (Photo credit should read JOSH EDELSON/AFP/Getty Images)
Storm chasing photographers take photos underneath a rotating supercell storm system in Maxwell, Nebraska on September 3, 2016. Although multiple tornado warnings were issued throughout the area, no funnel cloud touched down. / AFP / Josh Edelson / XGTY RESTRICTED TO EDITORIAL USE / MANDATORY CREDIT: "AFP PHOTO / Josh EDELSON" / NO MARKETING / NO ADVERTISING CAMPAIGNS / DISTRIBUTED AS A SERVICE TO CLIENTS == (Photo credit should read JOSH EDELSON/AFP/Getty Images)
PHOTO: JOSH EDELSON/AFP/AFP/Getty Images
Now playing
00:59
The difference between a tornado watch and a warning
DODGE CITY, KS - MAY 24: A tornado is seen south of Dodge City, Kansas moving north on May 24, 2016 in Dodge City, Kansas. About 30 tornadoes were reported on Tuesday in five different states from Michigan to Texas. Damage to homes and property was also reported in Ford County, Kansas. (Photo by Brian Davidson/Getty Images)
DODGE CITY, KS - MAY 24: A tornado is seen south of Dodge City, Kansas moving north on May 24, 2016 in Dodge City, Kansas. About 30 tornadoes were reported on Tuesday in five different states from Michigan to Texas. Damage to homes and property was also reported in Ford County, Kansas. (Photo by Brian Davidson/Getty Images)
PHOTO: Brian Davidson/Getty Images
Now playing
01:41
How to prepare for severe weather
weather storm chaser convergence nccorig_00010423.jpg
weather storm chaser convergence nccorig_00010423.jpg
Now playing
06:39
Traffic puts tornado chasers' lives in danger
Now playing
01:20
A 'dry' monsoon? They're more common than you think.
ring of fire chad myers weather orig_00003221.jpg
ring of fire chad myers weather orig_00003221.jpg
Now playing
01:13
What is the 'Ring of Fire'?
This picture taken on July 26, 2015 shows a child playing in a fountain on a square to cool himself amid a heatwave in Binzhou, eastern China
This picture taken on July 26, 2015 shows a child playing in a fountain on a square to cool himself amid a heatwave in Binzhou, eastern China's Shandong province. CHINA OUT AFP PHOTO (Photo credit should read STR/AFP/Getty Images)
PHOTO: STR/AFP/AFP/Getty Images
Now playing
01:14
What NOT to do in a heat wave
(CNN) —  

Much of the central Gulf Coast was under a hurricane warning late Monday as Tropical Storm Gordon, which is expected to strengthen, continued its march from the Florida Keys.

The warning covers all of coastal Mississippi and Alabama, the National Hurricane Center said.

Gordon could be a Category 1 hurricane before it makes landfall as early as Tuesday night. About 2 million people are under a hurricane watch or warning.

Gordon is expected to produce rain accumulations of 4 to 6 inches over southern Alabama, southern and central Mississippi, and southeastern and northeastern Louisiana, with isolated maximum amounts of 8 inches through late Thursday, according to the hurricane center.

Tropical Storm Gordon is expected to get stronger by Tuesday.
Tropical Storm Gordon is expected to get stronger by Tuesday.
PHOTO: CNN

By evening, the storm was headed west-northwest at 17 mph into the Gulf of Mexico and had maximum winds of 60 mph.

Gordon lashed south Florida with rain and tropical storm-force winds.

Geo Rodriguez decided to go for a walk on Hollywood Beach, north of Miami, on Monday morning and got caught in the storm. He captured video of people who were out and about, including a soaking-wet delivery person. Rodriguez said he is not concerned about the storm damaging his home

A storm surge watch was in effect from the Mississippi-Alabama border westward to the mouth of the Mississippi River.

“Gordon will bring heavy rainfall and tropical storm conditions to portions of South Florida and the Florida Keys today and a tropical storm warning is in effect for these areas,” the hurricane center said Monday.

’Get prepared’

PHOTO: CNN

Across the region, governments made their preparations. Louisiana Gov. John Bel Edwards declared a state of emergency, activating members of the National Guard.

New Orleans Mayor LaToya Cantrell issued a voluntary evacuation notice for areas outside of the New Orleans levee system ahead of Tropical Storm Gordon. Cantrell said the city expects to see impact of the storm beginning late Tuesday and continuing through Wednesday. City Hall and government offices will close Tuesday for nonessential employees.

In anticipation of heavy rains, the Flood Protection Authority-East (FPA) has closed 21 floodgates on the Lake Borgne Surge Barrier near New Orleans, according to a press release.

These gates are all in Orleans and St. Bernard parishes, primarily along the Industrial Canal and susceptible to high-tide conditions if not closed, the city says.

At this time, the FPA does not anticipate that the three pump stations at Lake Pontchartrain will be activated, but it is prepared to do so if the forecast changes and water levels reach key thresholds, according to the press release.

Florida Gov. Rick Scott tweeted that Floridians and visitors should monitor the weather system and remain vigilant.

“Right now, according to @NHC_Atlantic, the biggest impact to our state will be heavy rain, but in Florida, we know how quickly weather can change,” he said.

“With the peak of hurricane season upon us, now is the time to get prepared. Make sure that you and your family have a plan in place in case of disaster.”

CNN’s Dave Hennen, Haley Brink, Taylor Ward, Keith Allen and David Williams contributed to this report.