Official forecasts from the Finnish Meteorological Institute and supporting European models currently project a July 1 maximum in Helsinki near 21–24 °C, with the spread reflecting modest run-to-run differences in boundary-layer mixing, cloud cover, and weak southerly flow. Ensemble guidance shows limited warm-air advection ahead of a transient ridge, keeping values close to the early-summer climatological mean of roughly 20–22 °C while still allowing brief excursions to 25 °C if daytime insolation is stronger than expected. Traders have therefore concentrated probability on the 23–25 °C outcomes because those thresholds capture both the central forecast and the realistic uncertainty range two days before the event, whereas probabilities drop sharply outside this band once model consensus and historical verification skill are considered.