Heat in Hempstead, Arkansas

A large but strong upper level ridge of high pressure expanded from the Southern Rockies/Central and Southern Plains into the Mid-Mississippi Valley on August 15th, with compressional warming beneath the ridge contributing to extensive warming across much of Southwest Arkansas, Southeast Oklahoma, and East Texas. Sinking air beneath the ridge and strong insolation allowed for afternoon temperatures to climb into the upper 90s to near 100 degrees over these areas. When combined with the high humidity, heat indices ranged from 105-110 degrees across much of Southwest Arkansas, Southeast Oklahoma, and East Texas, which persisted through the 20th.