Phoenix starts Halloween under mostly cloudy skies, with a high near 77 degrees. The afternoon should remain mostly dry for a while, but a slight chance of showers and thunderstorms arrives after 5 p.m., ahead of a wetter night.
Flood Watch Covers the Phoenix Area
Showers and thunderstorms are expected to become widespread Saturday night, with a 100% chance of precipitation and rainfall totals between one-half and three-quarters of an inch. The National Weather Service in Phoenix says rain will continue through Sunday, when another three-quarters of an inch to 1 inch could fall across the area.
A Friday Hoodline forecast also described a wet Halloween weekend. The National Weather Service Flood Watch covers the Phoenix metro area, rural parts of Maricopa County and northwest Pinal County from Saturday night into early Monday morning, according to National Weather Service Phoenix.
Runoff Could Create Dangerous Conditions
Rain falling on already wet ground could run off quickly into washes, creeks, streams and other low-lying areas. Residents should avoid flooded roads and low-water crossings and be ready to act if Flash Flood Warnings are issued.
Checking Official Flood-Hazard Maps
For property-specific information, Maricopa County’s online maps page lists current and pending 100-year FEMA effective floodplain maps. The City of Phoenix says its Floodplain Management Ordinance maps and rates Special Flood Hazard Areas within the city. These resources show mapped floodplain information separately from this weekend’s temporary Flood Watch.
Rainfall amounts may vary across the Valley: roughly three-quarters of an inch to 1.75 inches is possible around Phoenix, with 2 to 4 inches possible in foothill and higher-terrain locations north and east of the city. Embedded thunderstorms could bring brief heavier downpours, lightning and locally strong wind gusts, though the overall setup is not expected to produce nonstop severe storms, according to National Weather Service Phoenix.
Rain Chances Fall After Sunday
Sunday is expected to be the coolest and wettest day of the stretch, with cloudy skies, showers and thunderstorms, and a high near 71 degrees. Rain chances remain high Sunday night before conditions improve late into Monday.
Monday is expected to be dry with sunshine and highs in the upper 60s to lower 70s. Tuesday through Friday could bring slowly warming temperatures through midweek and rain later.
