Recent forecasts from multiple models, including GFS and ECMWF integrations, indicate a frontal passage over Warsaw on September 17 that will limit daytime heating through increased cloud cover and showers, capping highs near 19°C. This follows warmer, sunnier conditions on the 16th, when southerly flow supported peaks around 23–24°C. Precipitation and reduced insolation are key differentiators among 17–20°C outcomes, as even modest rain timing or intensity shifts can alter surface energy balance by 1–2°C. Ensemble spreads show moderate uncertainty in exact frontal timing and moisture, keeping probabilities clustered across the 16–19°C range while rendering 22°C+ or sub-15°C scenarios unlikely under current synoptic patterns.