Bands of elevated showers/thunderstorms will likely continue to increase in coverage this morning across portions of northeastern Oklahoma and northwest Arkansas in the convergent zone of the low-level jet.
Very heavy rainfall will be likely in the stronger storms with in excess of 2 inches. The flash flood watch will be expanded to include a few more counties to the south and to include west-central Arkansas where training storms have developed.
South of the main precipitation, across far southeast Oklahoma, heat indices will likely climb into the 105 to 109 degree range this afternoon and will, therefore, go ahead and issue a heat advisory for the aforementioned area.
Still, the potential for scattered thunderstorms to redevelop tonight across portions of northeast Oklahoma/northwest Arkansas on periphery of the upper ridge but overall precipitation coverage is expected to be less compared to this morning.
The upper high will begin to build into the region from the south Saturday through Monday with very hot/humid conditions expected.