Milam County Judge Dave Barkemeyer says the storm hit a subdivision about 60 miles northeast of Austin. Barkemeyer says the man died when his mobile home was destroyed and that four other people were injured. No identities have been released.
The latest tragedy comes as 12 people remain missing after the vacation home they were staying in was swept away in the deadly floods that hit the region over the Memorial Day Weekend.
Evacuations were still underway in Austin, where the flooding has wreaked havoc.
Heavy rains have brought with them lightning, hail, tornadoes and flash floods that have destroyed more than 350 homes and left up to 1,000 people homeless.
The National Weather Service has declared a flash flood emergency for southwest Harris County in Texas as a severe storm brings heavy rain to the Houston area.
Around 200 basketball fans who attended a Houston Rockets game were stuck in the Toyota Center in Houston early Tuesday because of the severe weather.
The weather service reported 5 to 7 inches had fallen there Monday night and an additional 2 to 4 inches were possible.
More severe storms are forecast to hit Oklahoma and Texas, bringing with them more rain, hail and tornadoes.
Four people have now been confirmed killed in the deadly storms in Texas, while two more died in Oklahoma.
The Mexican city of Ciudad Acuna was devastated by a twister at daybreak Monday.
Officials in Mexico said at least 13 were killed in the tornado, the Associated Press reported. The city, population 100,000, is across the border from Del Rio, Texas.
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