Persistent heatwave conditions across North Texas, with mostly clear skies and southerly flow from the Gulf, are anchoring trader sentiment toward overnight lows near 84–87°F for Dallas on August 26. High dew points limit nocturnal radiative cooling, while the urban heat island effect and light winds sustain elevated minimum temperatures consistent with late-summer climatology. National Weather Service guidance and ensemble models show tight clustering around 79–83°F, but slight variations in cloud cover, boundary-layer mixing, or localized thunderstorm outflow can shift the actual minimum across the tightly bunched 84–89°F market tiers. No frontal passage is expected before resolution, keeping probabilities concentrated in this narrow range.