While October usually brings rain — 3.96 inches on average — accumulations have piled up at an unseasonable pace this year.

DRC/Al Key

This thunderstorm dropped a wall cloud over Denton between Interstate 35 and North Lakes Park earlier this year but produced only small hail along with very heavy rain.

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Another 0.43 inches of rain fell Sunday night into Monday, bringing the total to 12.06 inches for October, according to National Weather Service data. After a warm-up today, another cold front is expected to trigger rain Wednesday night into Thursday, bringing another 1 to 2 inches before the month’s end, according to meteorologists at the National Weather Service.

“By far, that’s not a record for Denton, but it’s in the top 5 percent,” meteorologist Mark Fox said.

According to precipitation records for Denton County, 11 inches of rain fell in 1919, and 10 inches of rain fell in 1971 and 1991.

Following a drought in summer 1991, a series of storms brought heavy rain the last week of October, with 10 inches falling in seven days. Flash flooding caused some street closures in Denton and a sewer line collapse in Aubrey. The problems spurred Denton’s call for improvements to be funded by a drainage fee, a policy that continues to spark controversy.

But 1981 brought the wettest October on record. After a storm dumped more than 4 inches of rain Oct. 6, remnants of a tropical storm were carried in by the jet stream from Mexico, bringing heavy rains for five days in mid-October and causing flooding in Cooke and Denton Counties.

The worst rain fell in Cooke County on Oct. 12, when 15 inches of rain forced evacuations of a wide area after the Moss Lake Dam broke. Floodwaters closed Interstate 35 and damaged every building at the Frank Buck Zoo in Gainesville, killing many animals housed there. About 7 inches of rain fell in Denton County, flooding streets and forcing the evacuation of several mobile home parks. Farmers estimated about $400,000 in losses to their crops and livestock.

As the rain continued, water levels at Lewisville Lake and Grapevine Lake rose as much as 6 inches per hour. Lewisville Lake crested over its spillway on Oct. 15.

DRC file photo

Standing water fills the yard of a house at Congress and Coit streets in mid-October 1981. Denton received a record 23.46 inches that month.

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By month’s end, the Denton Airport recorded 23.46 inches of rain. Nearby Gainesville reported 25 inches, so much as to almost be an aberration, Fox said.

Typically, about 37 inches of rain falls in Denton each year.

Flash flood watches could be part of Wednesday’s forecast, Fox said, but overall, that isn’t translating into flooding problems for area rivers and lakes.

According to the Texas Water Development Board Web site, Lewisville Lake is 3.61 feet above its conservation pool level, Grapevine Lake is 4.98 feet above and Ray Roberts Lake is 2.55 feet above.

The conservation pool elevation is the level at which the lake is full without flooding.

However, all this rain doesn’t bode well for fall color, according to Denton AgriLife Extension Service agent Janet Laminack.

“Dry weather and drought increase the sugars in the sap, which increases the anthocyanins, which is what gives the color,” Laminack said. “The sap is also sensitive to pH, which gives you those reds and purples. Ideal conditions for color include low temperatures and bright sunshine. The response is mostly to the light.”

“But we needed the rain,” she said.

PEGGY HEINKEL-WOLFE can be reached at 940-566-6881. Her e-mail address is pheinkel-wolfe@dentonrc.com .