A 43-year-old south Forsyth woman was killed and four other people, including three children, were injured in a two-vehicle collision Wednesday morning as thunderstorms soaked the area, authorities said.

Two of the four taken to area hospitals were in critical condition, according to Doug Rainwater with the Forsyth County Sheriff’s Office.

The sheriff’s office identified the woman as Tracy Bieler. Her 11-year-old daughter, who was the front seat passenger, remained in critical condition Wednesday night at Children’s Healthcare of Atlanta Scottish Rite.

The wreck, which authorities described as “weather related,” happened about 11 a.m. on Old Atlanta Road near Sharon Road.

Bieler was driving a 2002 Toyota Camry south, away from the Sharon crossing, when she lost control of the vehicle and crossed into oncoming traffic, Rainwater said.

The car was struck by a 2012 Honda Odyssey being driven by Mujtaba Syed, 40, of Cumming, Rainwater said.

“There’s no doubt weather was a factor,” he said, referring to the heavy rain at the time.

Syed and his 7-year-old son suffered what authorities described as non-life-threatening injuries as a result of the collision, as did an 11-year-old friend of Bieler’s daughter, who had been riding in the back seat of the Camry.

No charges have been filed, and the investigation remains ongoing, Rainwater said.

It was the first fatal wreck of the month on county roads and 12th of the year. Three people were killed in separate collisions over a six-day span July 22-28.

The collision appeared to be the most serious incident from a soggy Wednesday morning.

The National Weather Service issued a flash flood warning for the county as storms moved across the area, toppling trees and closing several roads.

Rainfall of up to 8 inches was measured in some areas of north Forsyth, according to the weather service.

The agency also reported flood water levels along Settingdown Creek.

Forsyth County Fire Division Chief Jason Shivers said a home on Settingdown Road was evacuated due to the rising water.

The house was “at or near being flooded,” he said, and the Red Cross was notified to assist the family.

Settingdown Road was also closed at the Hamptons subdivision.

According to the sheriff’s office, other local road closures included: Westbrook Road at Porter Lane; Grindle Lane; Burruss Mill Road at Burma Road; and Cantrell Road near Jot Em Down Road.

The 5400-block of Cantrell Road could be closed for two weeks.

Little Mill Road south of Keith Bridge Road was also shut down for a short period of time Wednesday.

In addition, a tree fell on Castleberry Road near the Wade Valley subdivision, blocking traffic, as did a tree on Majors Road between Castleberry and Hwy. 9.

According to the county government website, the following roads are also closed: Cantrell, Nicholson and Old Federal, as well as Dunroven Way.

The Big Creek Greenway, a popular walking and biking trail in south Forsyth, also is closed.