Traders see closely matched probabilities across mid-80s to low-90s buckets for Dallas’s August 24 minimum temperature because official forecasts remain uncertain amid a persistent heat wave and a possible tropical system. High pressure has kept overnight lows near 85–90 °F in recent days, but a tropical-storm threat noted for August 23–25 could increase cloud cover, bring scattered showers, and enhance mixing, all of which limit nocturnal radiative cooling and keep the minimum higher. Conversely, if the disturbance stays offshore or timing shifts, clearer skies would allow stronger cooling toward the low 80s or below. National Weather Service and private model runs diverge on the exact steering pattern and moisture arrival, creating the balanced market-implied odds around 79 °F or below versus 86–89 °F ranges. Historical August climatology places typical overnight lows near 75–77 °F, so any deviation hinges on whether the approaching system arrives before or after the 24-hour minimum is recorded.