Total streamflow across the Sulphur River was last observed at 11,870 cfs, and is expected to yield approximately 23,544 acre-ft of water today; about 105% of normal. Average streamflow for this time of year is 11,350 cfs, with recent peaks last observed on 2025-04-09 when daily discharge volume was observed at 36,400 cfs.

Maximum discharge along the river is currently at the Sulphur Rv Nr Texarkana reporting a streamflow rate of 9,550 cfs. This is also the highest stage along the Sulphur River, with a gauge stage of 30.77 ft at this location. This river is monitored from 3 different streamgauging stations along the Sulphur River, the highest being situated at an altitude of 290 ft, the Sulphur Rv Nr Talco.