The Climate Impact Company U.S. population weight CDD forecast for the 2026 warm season (Fig. 1) averages near or slightly below normal. The MAY/JUN (national) forecast is warm, near the 10-year normal, but lacking extreme heat as observed during MAY/JUN 2024 and JUN 2025. The JUL 2026 forecast is slightly below the 10-year normal and similar with the past 2 mid-summer(s). The AUG/SEP 2026 forecast is similar with 2024 and much warmer than last AUG. The hot bias for the warm season 2026 is in the West with marginal warmth in the high population East Coast.

The latest Canadian Meteorological Center (CMC) temperature and precipitation probabilistic 90-day outlook valid for MAY/JUN/JUL 2026 across Canada yields country-wide warmer than normal temperature with dryness favored across Southern Canada with a wet risk across Northern Canada.