Flooding emergency: Houston mayor warns holdouts they endanger crews the longer they wait to leave

The city of Houston and Harris County reported rescuing roughly 50 people since Thursday night as their messaging to those living next to rising rivers grew louder Friday afternoon: "Evacuate, if at all possible."

A few hours before sunset, Houston Mayor John Whitmire stood side by side with Harris County Precinct 3 Commissioner Tom Ramsey in Kingwood, where it serves as the San Jacinto River's key drainage point.

Consecutive days of rain over the past week have prompted water releases by the San Jacinto River Authority and the Lake Livingston Dam Authority. And, according to the ABC13 weather team, a storm capable of dumping heavy rain may make things worse on Sunday.

Based on best estimates, Whitmire told reporters the East Fork of the San Jacinto River was set to peak between 10 p.m. and 11 p.m. on Friday while the West Fork will do the same from 3 p.m. to 5 p.m. on Saturday. This was updated from an earlier estimate suggesting peaking for both forks during Saturday afternoon.

Ramsey added that Friday afternoon would be the best time for crews to evacuate people, warning those who live along the river and tributaries that they could put rescuers at risk during the nighttime.

SEE MORE: ABC13 captures neighbors' hope and heartbreak amid flooding emergency: 'Lost basically everything'

"People that are east, that are west of (FM) 2100 on the San Jacinto River need to get out now," Ramsey said, adding that the river's 74-foot water level should go up another 3 feet before midnight Friday.

Ramsey singled out Idle Glen subdivision, North Wood Country Estate, River Terrace, and Cypress Point. A resource in English and Spanish is available for locations under evacuation orders and shelters.

Whitmire added that he's been in contact with Gov. Greg Abbott and Nim Kidd, the chief of the Texas Division of Emergency Management, regarding resources.

According to Whitmire, shelters are in place, and METRO is on call to furnish transportation.

Crews also told neighbors to remain vigilant, even without the rain falling.

"Don't let the break in the weather give you a false sense of security," Houston Fire Department Chief Samuel Pena said. "We should take advantage of this break in the weather."

Earlier, Harris County Judge Lina Hidalgo planted seeds of the danger ahead, warning homeowners to brace for additional damage with more rain on the way during a potentially catastrophic event.

More than 700 Polk County homes upstream have flooded.

"This is not what happened in January. This is much worse. It's a catastrophic event. And we all need to take the urgent and necessary steps to respond accordingly," Hidalgo said.

Polk is among the counties that have been repeatedly drenched over the past two days. Parts of San Jacinto, Montgomery, Liberty, Walker, Chambers, Grimes, Madison, Trinity and Harris counties have also been affected.

Here's what else to know as this flooding emergency continues.

What we're watching

By far, the biggest concern is the swollen San Jacinto River, which is expected to have impactful flooding through the weekend that may last into Monday, said Harris County Flood Control District meteorologist Jeff Lindner.

Lindner also warned that people should be prepared for rapidly rising and swift water throughout the system.

He also said on X, formerly Twitter, that dangerous flooding would be likely on the East Fork of the river.

"The good news is we have not seen any significant changes in the height of those peaks. So we're still looking at the same height that we've been expecting the whole time on the East Fork, roughly the same height on the West Fork," Lindner said.

The peak is described as the maximum height and maximum extent when the water spreads out.

"And then it's going to start going down, and that extent starts shrinking back in toward the river," Lindner explained.

Where are evacuations mandatory and where are they voluntary?

Time is running out to determine whether a resident wants to heed evacuation orders. Those closest to the river are most at risk.

"We can't force somebody to leave. But if you stay there, not only are you a sitting duck, but you're putting our law enforcement in danger. And at some point we can't send law enforcement into swift water that is sure to pose a threat to their life because you made a bad decision," Hidalgo said. "Please evacuate if you are on the East Fork of the San Jacinto river half a mile from the river towards the east."

Hidalgo also said that if someone chooses to stay, "be ready to shelter in place for the next two to three days."

SEE ALSO: Boil water notice issued for several Lake Livingston - area subdivisions

Mandatory evacuation areas

East Fork of the San Jacinto River from FM 1485 to Lake Houston (up to a half mile from the river)

Idle Glen / Idle Wilde Subdivision:

Streets affected include Brookside, Chinquapin, River Side, E. San Jacinto, Glenwood, Dipping, Idlewilde, and Lazy Creek.

Northwood Country Estates:

Streets affected include Disher, Bounds, Thomas, and Davidson.

River Terrace:

Streets affected include River Terrace, Elm, Pine, Cherry Laurel, Holly, and Cypress. Elevated homes could be isolated.

Cypress Point:

Streets affected include Blue Lake, Oak Knoll, Wild Oak, and Birchwood. Elevated homes in these areas will also be isolated.

Commons of Lake Houston (formerly known as Magnolia Point):

Streets affected include Opal Way, Diamond, Mendencino, Lassen Villa, Glen, Magnolia, Hill, Calvins, Collins, and Calaveras Creek.

South of FM 1485 (on east side of the river):

Streets affected include Spalding, Green, Jett, and Casey.

Voluntary evacuation areas:

Kingwood, nearest the San Jacinto River:

Residents should either plan to stay where they are for the next 2-3 days or leave as soon as possible if they are not prepared to do that. If they plan to leave, they need to leave before nightfall Thursday.

Forest Cove, North Shore, Belleau Wood, and River Crest:

Residents should either plan to stay where they are for the next 2-3 days or leave as soon as possible if they are not prepared to do that. If they plan to leave, they need to leave before nightfall Thursday.

Kings River and Atascocita Shores:

Residents should either plan to stay where they are for the next 2-3 days or leave as soon as possible if they are not prepare to do that. If they plan to leave, they need to leave before nightfall Thursday.

Voluntary evacuation areas (by Friday night):

Rio Villa:

Residents have until Friday nightfall to either plan to stay where they are for the following 2-3 days or leave as soon as possible if they are not prepared to do that. In Rio Villa, the water is not expected to peak Friday night since Rio Villa is farther south.

Wallisville Road may be impassable on Saturday.

You can check the latest evacuation information on the Ready Harris website.

If you plan to ride it out, remember you need six gallons of water per person, per day. You'll also need to be sure to have enough food for your family and any pets and medicine.

Lake Conroe Dam releases

The San Jacinto River Authority (SJRA) began releasing water from Lake Conroe Dam Thursday. But it's not the main source of flooding issues for communities along the river, Hidalgo said.

"That water accounts only for about 20% of the water that gets there, and here's why. The watershed that Lake Conroe is in is actually quite small. The watersheds next to it, Little Cypress Creek watershed, Spring and Lake Creek watersheds, they're much larger, so there's much more water that is coming from there to the San Jacinto River," she explained.

SJRA is required to maintain a certain water level as the dam also serves as a water source for the city of Houston.

She added that the river authority has to raise a gate, and if the water gets too high, the water will come out below. If water gets over the gate, it could cause catastrophic damage, especially for those who live south of the dam.

As of 11:30 a.m., Friday, SJRA said it reduced the release from Lake Conroe to 38,450 cubic feet per second (CFS).

You can follow the river authority online for updates on releases.

Lake Conroe is closed.

Shelters

A number of shelters are still open, though the Leon Grayson Community Center has since closed.

• Philippians New Faith Baptist Church (capacity 20): 7858 Angus St, Houston, TX 77028

• Calvary Baptist Church: 816 N Blair Ave, Cleveland, TX 77327

• Greenhouse International Church: 200 W Greens Rd, Houston, TX 77067

Status of the hospitals

If people needed another incentive to evacuate from an area where leaving is mandatory, Hidalgo said, it might be that the hospitals are full.

Memorial Hermann and Ben Taub Hospital have a level one trauma center, which can handle the toughest of emergencies.

"They're red. They're very full right now. The highest level of acuity hospitals are pretty much the fullest they can be," she said.