A Severe Thunderstorm Warning has been issued for the following county in Oklahoma: Ottawa until 2:00 PM. ... A Heat Advisory has been issued for the following counties in Oklahoma: Atoka, Bryan, Canadian, Carter, Cleveland, Coal, Garvin, Grady, Hughes, Jefferson, Johnston, Kingfisher, Lincoln, Logan, Love, Marshall, McClain, Murray, Oklahoma, Payne, Pontotoc, Pottawatomie, Seminole and Stephens until 7:00 PM and the following counties in Oklahoma: Adair, Cherokee, Choctaw, Creek, Haskell, Latimer, Le Flore, McIntosh, Muskogee, Okfuskee, Okmulgee, Pittsburg, Pushmataha, Sequoyah, Tulsa and Wagoner until 8:00 PM.