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Noticeably cooler Canadian air surging into the Eastern U.S. this past weekend marks start of the most prolonged period of mild conditions absent heat and uncomfortable humidity of the 2025 warm season. A lead fall-like surface cold front already through the northeast quadrant of the U.S. on track to reach central portions of the Gulf Coast Monday night, with a 2^nd reinforcing cold front forecast to follow a similar path late in the workweek (Aug 29), led to markedly colder model shifts (10°-15° below average) across all of the Eastern half of the U.S. in forecasts valid through the next 10-days. Part of colder model shifts is greater rainfall forecast from the central Plains into the Southeast and Florida. Models struggle greatest with precipitation forecasts suggesting subsequent runs are likely to trend wetter and cooler well into the 1^st week of September.  In contrast hotter for longer model forecasts across the Pacific Northwest are directly related to recent consensus maintaining far more resilient Western ridging. All extended range models progressively de-amplify large scale flow during the 11-15 day period, but also maintain greatest U.S. ridging between the West and Plains. This significant government model forecast shift strongly supports similar longer range 30-day MWA forecasts valid into late September. Coupled with very warm ocean temperatures along nearly all U.S. coastlines (lone exception is Southern California) this is a mild scenario featuring seasonal to moderate above average temperatures devoid of extremes across the vast majority of the U.S. considered likely to persist into mid fall (October). Meanwhile Tropical Storm Fernand recently formed in the tropical Atlantic on Saturday, but is forecast to be deflected much farther offshore than Erin representing no threat to the U.S. However, NHC is monitoring another area in the Caribbean (Invest 99) as the recent period of enhanced tropical activity in the Atlantic Basin persists into September.