WWUS74 KTSA 201712 NPWTSA Heat Advisory National Weather Service Tulsa OK 1212 PM CDT Thu Aug 20 2026 ARZ129-219-220-229-OKZ065-066-070-071-073>075-176-272-276-376 /O.CON.KTSA.HT.Y.0040.260820T1800Z-260821T0100Z/ North and Central Sebastian-Southern Crawford-Central and Southern Franklin-Southern Sebastian-Okfuskee-Okmulgee-Muskogee-McIntosh-Pittsburg-Haskell-Latimer-Northern Le Flore-Central and Southern Sequoyah-Central Le Flore-Southern Le Flore ...HEAT ADVISORY IN EFFECT FROM NOON TO 8 PM CDT FRIDAY... ...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM CDT THIS EVENING... * WHAT...Heat index values up to 109 expected. * WHERE...Portions of northwest and west central Arkansas and east central, northeast, and southeast Oklahoma. * WHEN...For the first Heat Advisory, until 8 PM CDT this evening. For the second Heat Advisory, from noon to 8 PM CDT Friday. * IMPACTS...Heat related illnesses are possible especially impacting those not acclimated to the conditions or those performing strenuous activities. Take extra precautions when outside. Wear lightweight and loose fitting clothing. Try to limit strenuous activities to early morning or evening. Take action when you see symptoms of heat exhaustion and heat stroke..