August means football practice for thousands of Texas teenagers, stars in one of the state's most passionate pastimes. It won't be the same in this year of deadly heat.

Weeks of triple-digit temperatures have been the norm in much of the state, a red-flag condition signaling that schools and coaches must make concessions to keep youngsters safe.At Dallas Academy, a private secondary school of 140 students, football players must show up at 6:45 a.m. instead of the traditional 3 p.m. practice time.

"They're wearing pads and helmets - we don't want anyone to have heat stroke out there," school director Jim Richardson said Thursday.

The searing, unrelenting heat is blamed for 99 deaths statewide, with no end in sight to a 25-day string of 100-degree temperatures in northern Texas. Readings could soar to 105 today.

Nationwide, at least 144 deaths are blamed on the heat wave since May.

Texas schools typically get a jump on the national back-to-school date near Labor Day. With many schools set to open Monday, legions of youngsters likely will trek back to class in withering heat.

Health experts are warning people to drink plenty of water, and that goes for everyone: children, elderly people and folks who must be outdoors.

Temperatures hit 103 degrees at noon Thursday as Plano High School band members stood in formation on hot asphalt.

"It's hot and it's unbearable," said trumpeter Patrick Shay, who with his bandmates took water breaks every 20 minutes.

At St. Mark's School of Texas in Dallas, football players "are going to be out early in the morning, they'll be in an air-conditioned building in the middle of the day, and then maybe they'll go out again later," said Jim Kirkpatrick, chief financial officer at the all-boys school.

All outdoor activities will be limited on days when either the heat or pollution is deemed too heavy to be safe for the boys, Kirkpatrick said.