Chart of the day: Summertime 2022 weekly U.S. CDD totals.
Discussion: Using NOAA population weight CDD observations, the U.S. weekly population weight CDD was variable – normal and warm – early during summer 2022. The hottest part of summer climatologically is when the hottest weekly CDD count occurred in July. Recently, briefly cooler national CDD was observed. The warm season 2022 finishes somewhat warmer than normal.
Week-2 Ahead Forecast valid September 5-11, 2022: Forecast trend is warmer, South stays wet. Tropical systems out-to-sea.
Discussion: The first full week of September maintains a similar theme to the previous forecast except warmer, still wet in the South (but wetter) and emerging tropical systems staying out-to-sea. California is the hot spot! The Northeast high energy demand zone is very warm and humid. Some of the Southern rain extends northward therefore the Great Plains forecast is not as dry as previously indicated.
Week-3 Ahead Forecast valid September 12-18, 2022: California rains!
Discussion: ECMWF parks an upper trough over the West Coast and operational models are trending in that direction. Consequently, an unusually wet period is forecast for California into mid-September. Heavy rain is possible which brings complications – especially mudslides given the arid terrain from long-term drought. The Central U.S. forecast may be too warm. The only dry zone is the Ohio Valley for mid-month. Tropical cyclone risk is north-northeast of the Bahamas.
Week-4 Ahead Forecast valid September 19-25, 2022: Central to Northeast warmth. Northeast Gulf tropical cyclone risk.
Discussion: The Great Plains is potentially hot during later September due to the excessive dry soils. The warmth in the Central Plains is a source region for late season warmth extending across the Northeast States. A tropical cyclone risk in the Gulf region is a confident forecast.