Address reportCitiesArizona › Phoenix

Phoenix, AZ

Earthquake hazard, typical weather and growing season from public federal data. Population 1,513,367.

Flood zone: it depends on the exact parcel

There is no such thing as a flood zone for a whole city. Two houses on the same street can sit in different zones, and it is the single fact here that changes most over a short distance. So this page does not guess one.

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Earthquake hazard low

Design category B

Low seismic hazard. Earthquakes are infrequent and usually minor here, but the building code still applies light seismic detailing to new construction. The ASCE 7 Seismic Design Category here is B. (Short-period design value Ss ≈ 0.179 g — the standard headline measure of ground-shaking hazard.)

USGS Seismic Design Web Services (ASCE 7), assuming Site Class D — stiff or unknown soil. Real soil conditions can move the category either way.

Typical weather

102.5° in July, 40.5° in December

Thirty-year averages, not a forecast. Any individual year can differ substantially.

MonthHighLowRainSnow
Jan66.9°41.7°0.87"0"
Feb71.1°44°0.99"0"
Mar77.6°48.4°0.95"0"
Apr85°53.8°0.26"0"
May92.5°61.5°0.11"0"
Jun100.9°69.3°0.05"0"
Jul102.5°77.2°0.76"0"
Aug101.1°77.5°0.75"0"
Sep97°71.3°0.59"0"
Oct86.9°59°0.66"0"
Nov74.3°47.6°0.69"0"
Dec65.2°40.5°0.78"0"

NOAA/NCEI 1991–2020 U.S. Climate Normals — station SOUTH PHOENIX, AZ US, 9 mi away.

Growing season zone 9b

365 frost-free days

Last spring frost around n/a, first fall frost around n/a. Roughly half of years see frost outside that window.

2023 USDA Plant Hardiness Zone Map and NOAA/NCEI 1991–2020 frost normals.

What this page does not tell you

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