Current forecasts from global and regional models indicate a highest temperature in Buenos Aires on May 18 most likely between 15°C and 17°C, driven by a stable post-frontal air mass with moderate southerly flow and variable cloud cover limiting daytime heating. Ensemble guidance shows limited spread around this range, with slight model disagreement on the exact timing of any clearing that could allow brief warming to 17°C or keep readings capped near 15°C under thicker low-level stratus. Historical May climatology places the long-term average high near 17°C, providing context for why traders assign comparable probabilities across these three outcomes rather than a single dominant result. Updated model runs and local observations from the Servicio Meteorológico Nacional will refine the final range before resolution.