Overview
- A broad high‑pressure ridge is keeping most of the country dry and mild early this week before three separate systems approach midweek and late week.
- A low moving down the West Coast will cool Southern and parts of Central California and bring moderate rain Wednesday–Thursday with typical totals of 0.75–1 inch and up to about 2 inches on coastal slopes and foothills.
- A moisture‑rich Pacific storm will tap unusually high humidity for the season and has prompted a Flood Watch for parts of the Phoenix area from 8 p.m. Wednesday through 5 p.m. Thursday with rain rates that could reach 1–2 inches per hour and a risk of flash flooding and isolated severe storms.
- An offshore coastal low that may gain subtropical traits is forecast to lift north off the Southeast and could produce gusty northeast winds, high surf, dangerous rip currents, and localized coastal flooding on Cape Cod and nearby islands depending on its track.
- Forecast uncertainty remains over exact tracks and timing so local impacts will vary; officials urge following National Weather Service watches, beach‑hazard products, and guidance for flooded roads, travel delays, and wind‑driven hazards.