With five states of emergency already declared in the states of North Carolina, South Carolina, Maryland, Virginia, and Georgia, Hurricane Florence looks to make landfall on Thursday night with catastrophic impact. The category 3 storm (which is currently the size of Michigan) is expected to cause catastrophic conditions, if the predictions hold true, with gale-force winds and torrential downpours especially in the state of North Carolina.

As of Wednesday, just over 24 hours before the storm’s predicted landfall, the National Weather Service lists the two greatest impacts of the storm to be flash flooding and river flooding. What’s more, the NWS predicts upwards of 20 inches of rainfall along the coast of North Carolina, with other areas predicted to receive 10+ inches of rain as well.

Here’s what you need to know about North Carolina’s flooding predictions leading up to Hurricane Florence’s arrival.

7-Day Rainfall Forecast Predicts Mass Rainfall All Over North Carolina, Which Is Likely to Cause Flooding

Accuweather reports that residents of the Carolina coastline should expect to be “bombarded” with rain and heavy wind from Thursday to Saturday. Though NWS estimates upwards of 20 inches of rainfall along the coastline, Accuweather is estimating closer to 40 inches, which could lead to catastrophic levels of flooding from the coastline inland.

NWS confirms that “major to extreme flooding” is likely across central and eastern North Carolina, as Hurricane Florence threatens to pound the state for a full 24 hours.

Weather.com notes that the runoff from this rain will accumulate for several days, and will eventually enter the riverways of the Carolinas and potentially cause swelling of these rivers for multiple months.

North Carolina Rivers With a High Likelihood of Flooding, as of September 13

According to the NWS, the areas that are vulnerable to the most severe levels of flooding (which could surpass that of Hurricane Floyd’s river impact) are the following:

Trent River (Jones County)

New River (Onslow County)

Swift Creek (Craven County)

NE Cape Fear (Duplin County)

NSW warns of “major river flooding” that might occur for multiple weeks, and notes that “travel will be nearly impossible with numerous roads countywide impassable or washed out… [and] many homes across the county are inundated.”

Here are predicted flood maps provided by NWS so far:

New River, Near Gum Branch

Trent River in Trenton & Pollocksville

Predicted Flood Zones in North Carolina as of Wednesday, September 12

The state of North Carolina has set up a Flood Risk Information System that will allow residents to see what the risk of flooding is in their area. Currently, the NWS lists the counties believed to be at risk of flooding in the southeast area of North Carolina:

Bladen

Coastal Brunswick

Coastal New Hanover

Coastal Pender

Columbus

Inland Brunswick

Inland New Hanover

Inland Pender

Robeson

Significant Storm Surges of up to 13 Feet Are Expected Along the Coastline

Storm Surge Like You've Never Experienced it BeforeWhat does 9 feet of storm surge look like? We show you like nobody else can. This was the forecast storm surge for the Carolina coast as Hurricane Florence was approaching. ** Forecast data from Sept 12th at 5:00 PM (ET)** 2018-09-12T20:51:57.000Z

Significant storm surges are expected along the coastline, with tidal rises of anywhere from six to 13 feet, according to The Weather Channel. Combined with rainfall, this flooding could lead to incredibly damaging flooding along the coastline and much farther inland.

To put it into perspective, The Weather Channel estimates that storm surges of nine feet could cause floods that are so high they might cover the entire first floor of buildings.

Weather.com says of the expected storm surges: “A destructive storm surge will accompany the eye coming ashore sometime from Thursday night into Friday or Saturday, and coastal flooding may persist through multiple high tide cycles into this weekend east of the center of Florence. Large, battering waves will ride atop this surge. All evacuation orders from local officials should be followed because of this dangerous threat. Significant beach erosion is also likely on the southeastern U.S. coast. Elevated water levels may persist for some time after landfall in areas where onshore winds persist.”

Here are the latest storm surge estimates from the National Hurricane Center, as of Wednesday:

Cape Fear to Cape Lookout, North Carolina, including the Neuse, Pamlico, Pungo and Bay Rivers: 9 to 13 feet

North Myrtle Beach, South Carolina, to Cape Fear, North Carolina: 6 to 9 feet

Cape Lookout, North Carolina, to Ocracoke Inlet, North Carolina: 6 to 9 feet

South Santee River, South Carolina, to North Myrtle Beach, South Carolina: 4 to 6 feet

Ocracoke Inlet, North Carolina, to Salvo, North Carolina: 4 to 6 feet

Salvo, North Carolina to the North Carolina/Virginia border: 2 to 4 feet

Edisto Beach, South Carolina, to the South Santee River, South Carolina: 2 to 4 feet

READ NEXT: South Carolina Flooding Maps & Projections for Hurricane Florence