Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 98648 — Stevenson, WA

ZIP code 98648 (Stevenson, Skamania County) is in USDA zone 8a: the coldest winter night averages 10 to 15 °F. The median last spring frost is March 24 and the first fall frost November 20.

Where ZIP 98648 is

Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone8a10 to 15 °F

Coldest night−12.2 to −9.4 °C

Last frostMar 24

First frostNov 20

2012 zone8a

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 8a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Stevenson, WA…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates in Stevenson, WA

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostMarch 24median — 50% chance of a later frost

Safe for tender plantsApril 16only 10% chance of frost after

First fall frostNovember 20median — 10% chance by Nov 1

Growing season242 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 24 and returns around December 9.

From the NOAA station Cascade Locks, OR — 4 miles away, elevation 141 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in 98648

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 10 – Feb 24

SpinachSow outdoors · Feb 10 – Mar 3

Broccoli, cabbageStart indoors · Jan 13 – Jan 27

Broccoli, cabbageTransplant · Mar 3 – Mar 17

Onion setsPlant outdoors · Feb 24 – Mar 10

PotatoesPlant outdoors · Mar 3 – Mar 17

LettuceSow outdoors · Feb 24 – Mar 10

Carrots, beetsSow outdoors · Mar 3 – Mar 17

TomatoesStart indoors · Jan 27 – Feb 10

TomatoesTransplant · Mar 31 – Apr 14

Peppers, eggplantStart indoors · Jan 13 – Jan 27

Peppers, eggplantTransplant · Apr 7 – Apr 21

BeansSow outdoors · Mar 31 – Apr 14

Sweet cornSow outdoors · Mar 31 – Apr 14

Cucumbers, squashSow outdoors · Mar 31 – Apr 14

Fall lettuce, spinachSow outdoors · Sep 25 – Oct 9

GarlicPlant cloves · Nov 6 – Dec 11

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 24) and first fall frost (Nov 20) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

When spring arrived in 2026

In 2026, spring leaf-out near 98648 came on Mar 11 — 12 days earlier than the 1991–2020 average (Mar 23).

average
Mar 232026
Mar 11

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Native plants for zone 8a in Washington

611 plants native to the lower 48 states, recorded in Washington, and rated by the USDA to survive 10 °F or colder — the bottom of zone 8a. Each links to its USDA PLANTS profile.

Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in Stevenson, WA.

Soil in Stevenson, WA

The soil mapped at the center of ZIP 98648 is Steever — stony clay loam, well drained.

TextureStony clay loamholds water and nutrients; slow to drain and warm up

pH5.6moderately acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter1.5%low — add compost

Hydrologic groupBwater soaks in moderately

Farmland classFarmland of statewide importanceUSDA classification

Map unit: Steever stony clay loam, 2 to 30 percent slopes.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 98648; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Stevenson, WA

Summer high82 °Faverage high, August

Winter low33 °Faverage low, January

Hot days17days a year at 90 °F or more

Freezing nights55nights a year at 32 °F or less

Growing degree days2,435base 50 °F — the season’s usable heat

Longest day15 h 43 mindaylight on June 21

Shortest day8 h 40 mindaylight on December 21

Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Precipitation80.2 inper year, rain and melted snow

Snowfall10 inper year; 6 days with snow on the ground

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Cascade Locks, OR (4 mi away); precipitation: Bonneville Dam, OR (5 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

4 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

986399a

North Bonneville, WA · 5 mi

986108a

Carson, WA · 6 mi

970148a

Cascade Locks, OR · 9 mi

986057b

Bingen, WA · 14 mi

986518a

Underwood, WA · 18 mi

970317b

Hood River, OR · 18 mi

970198b

Corbett, OR · 19 mi

970118a

Brightwood, OR · 22 mi

Washington planting zones →

Questions about 98648

What planting zone is ZIP code 98648?

ZIP code 98648 (Stevenson, WA) is in USDA hardiness zone 8a on the 2023 map: the coldest night of an average winter reaches 10 to 15 °F (−12.2 to −9.4 °C).

When is the last frost in Stevenson, WA?

The median last spring frost (32 °F) near 98648 is March 24; after April 16 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Cascade Locks station.

When is the first frost in Stevenson, WA?

The median first fall frost near 98648 is November 20, giving a median frost-free growing season of 242 days.

When should I plant tomatoes in 98648?

Start tomato seeds indoors around Jan 27 – Feb 10 and set transplants outside around Mar 31 – Apr 14, one to three weeks after the median last frost.

How much rain and snow does 98648 get?

About 80.2 inches of precipitation a year and 10 inches of snowfall (NOAA 1991–2020 normals, Bonneville Dam station).

How hot do summers get in Stevenson, WA?

The average high peaks at 82 °F in August, with about 17 days a year at 90 °F or more.

What kind of soil does 98648 have?

The USDA soil survey maps Steever at the center of ZIP 98648: stony clay loam, well drained, pH about 5.6 (moderately acidic).

Did spring come early in Stevenson, WA in 2026?

Spring leaf-out near 98648 came on Mar 11 in 2026, 12 days earlier than the 1991–2020 average (Mar 23), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Stevenson, WA?

Long-day onions: the longest day near 98648 is 15 h 43 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).