A wildfire that scorched about 50,000 acres in western Texas was nearly contained Wednesday as firefighters across the state monitored flare-ups amid slightly lighter winds and cooler temperatures.

The blaze, which stretched across Irion and Reagan counties west of San Angelo, was the last major wildfire in Texas.

Grass fires started by as little as a spark from a car or downed power lines have burned more than 600,000 acres across a drought-stricken stretch of Oklahoma, Texas and New Mexico in the past week and a half. The fires have destroyed at least 470 homes and killed five people.

Officials in New Mexico contained a grass fire there Tuesday night. Fires were largely contained in Oklahoma, but more were expected, with highs in the low 60s and winds of up to 20 mph in some areas. No rain was in the forecast.

"It's one thing to be dry. It's another thing to be dry and have above-average temperatures like we've had the last two weeks," National Weather Service forecaster Bruce Thoren said.

A fire that was contained Tuesday in Shamrock that destroyed an abandoned school house and one home was likely set by an arsonist, said Loren Andrews, the assistant fire chief in nearby Drumright.

The Federal Emergency Management Agency announced it had approved requests from Texas, Oklahoma and New Mexico for assistance from the nation's Disaster Relief Fund to aid in firefighting efforts.