Current forecasts from multiple meteorological models indicate a maximum of 17–18°C in Warsaw on September 26 under mostly cloudy skies, light southwest winds, and building high pressure near 1023 hPa, which limits daytime radiative heating. Persistent cloud cover reduces solar insolation during the post-equinox period when incoming radiation is already declining, while cooler maritime air advection from the west maintains moderate temperatures consistent with late-September climatology. Recent model runs show minimal day-to-day shifts, with low precipitation risk and no signals for stronger warming or cold-air outbreaks. These conditions support the market's heavy weighting toward 17–18°C outcomes, as traders incorporate the consensus range from official guidance.