Thunderstorms brought on flooding and apparently caused a plane crash that killed four people in Texas, while the East enjoyed record high temperatures of up to 90 degrees in Baltimore and 81 in Boston. Flash-flood watches were posted in northeast Texas and extreme southeast Oklahoma and all of Arkansas. As much as 5 inches of rain fell overnight in the Dallas-Ft. Worth area, and 4 inches soaked sections of South Texas, the National Weather Service said. Flooding was reported along Cowhouse Creek at Ft. Hood, Tex. A private single-engine airplane crashed in a remote part of the Texas Hill Country during a heavy thunderstorm, killing all aboard, Medina County authorities said.