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

Planting zone for 98639 — North Bonneville, WA

ZIP code 98639 (North Bonneville, Skamania County) is in USDA zone 9a: the coldest winter night averages 20 to 25 °F. The median last spring frost is March 14 and the first fall frost November 27.

Where ZIP 98639 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.

Zone9a20 to 25 °F
Coldest night−6.7 to −3.9 °C
Last frostMar 14
First frostNov 27
2012 zone8b

Was 8b on the 2012 map — half a zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 9a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for North Bonneville, 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 North Bonneville, WA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMarch 14median — 50% chance of a later frost
Safe for tender plantsApril 4only 10% chance of frost after
First fall frostNovember 27median — 10% chance by Nov 8
Growing season257 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 14 and returns around December 14.

From the NOAA station Bonneville Dam, OR — within 1 mile, elevation 62 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 98639

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Jan 31 – Feb 14
SpinachSow outdoors · Jan 31 – Feb 21
Broccoli, cabbageStart indoors · Jan 3 – Jan 17
Broccoli, cabbageTransplant · Feb 21 – Mar 7
Onion setsPlant outdoors · Feb 14 – Feb 28
PotatoesPlant outdoors · Feb 21 – Mar 7
LettuceSow outdoors · Feb 14 – Feb 28
Carrots, beetsSow outdoors · Feb 21 – Mar 7
TomatoesStart indoors · Jan 17 – Jan 31
TomatoesTransplant · Mar 21 – Apr 4
Peppers, eggplantStart indoors · Jan 3 – Jan 17
Peppers, eggplantTransplant · Mar 28 – Apr 11
BeansSow outdoors · Mar 21 – Apr 4
Sweet cornSow outdoors · Mar 21 – Apr 4
Cucumbers, squashSow outdoors · Mar 21 – Apr 4
Fall lettuce, spinachSow outdoors · Oct 2 – Oct 16
GarlicPlant cloves · Nov 13 – Dec 18
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 14) and first fall frost (Nov 27) 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 98639 came on Mar 2 — about the same time as the 1991–2020 average (Mar 4).

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 9a in Washington

617 plants native to the lower 48 states, recorded in Washington, and rated by the USDA to survive 20 °F or colder — the bottom of zone 9a. Each links to its USDA PLANTS profile.

Trees 32

Alaska cedar75 ft · blooms mid spring · low shade tolerance · to −22 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Fbalsam poplar80 ft · blooms late spring · high shade tolerance · to −79 °Fbigleaf maple60 ft · blooms mid spring · medium shade tolerance · to −14 °Fblack locust60 ft · blooms spring · high shade tolerance · to −37 °Fboxelder60 ft · blooms early spring · low shade tolerance · to −46 °F

Shrubs 115

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAllegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °Falpine laurel1 ft · blooms late spring · low shade tolerance · to −28 °FAmerican plum24 ft · blooms mid spring · high shade tolerance · to −38 °Fantelope bitterbrush6 ft · blooms early spring · medium shade tolerance · to −36 °FBarclay's willow15 ft · high shade tolerance · to −43 °F

Wildflowers & perennials 293

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine bistort1 ft · blooms mid spring · high shade tolerance · to −38 °Falpine mountainsorrel1 ft · blooms mid summer · medium shade tolerance · to −43 °FAmerican alpine speedwell1 ft · blooms summer · medium shade tolerance · to −28 °FAmerican bistort1.5 ft · blooms mid spring · high shade tolerance · to −38 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °F

Grasses 159

Alaska brome5 ft · blooms late spring · low shade tolerance · to −18 °FAlaska oniongrass3 ft · blooms mid spring · low shade tolerance · to −33 °Falkali cordgrass3 ft · blooms late summer · high shade tolerance · to −38 °Falkali sacaton3 ft · blooms mid summer · high shade tolerance · to −38 °Falpine timothy1.4 ft · blooms late spring · medium shade tolerance · to −43 °FAmerican beachgrass2.5 ft · blooms spring · high shade tolerance · to −28 °F

Vines 3

riverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Ftrumpet creeper2 ft · blooms summer · high shade tolerance · to −13 °Fwestern white clematis1 ft · blooms mid summer · medium shade tolerance · to −38 °F

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 North Bonneville, WA.

Soil in North Bonneville, WA

The soil mapped at the center of ZIP 98639 is Pilchuck — very fine sandy loam, somewhat excessively drained.

TextureVery fine sandy loamdrains and warms fast; dries out and needs more feeding
pH6.1slightly acidic; most vegetables like 6.0–7.0
DrainageSomewhat excessively drainednatural drainage class
Organic matter1.5%low — add compost
Hydrologic groupBwater soaks in moderately
Farmland classPrime farmland if protected from flooding or not frequently flooded during the growing seasonUSDA classification

Map unit: Pilchuck very fine sandy loam.

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 98639; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in North Bonneville, WA

Summer high80 °Faverage high, August
Winter low34 °Faverage low, January
Hot days11days a year at 90 °F or more
Freezing nights33nights a year at 32 °F or less
Growing degree days2,407base 50 °F — the season’s usable heat
Longest day15 h 42 mindaylight on June 21
Shortest day8 h 41 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

20°30°40°50°60°70°80°90°32 °FJanuary: average high 43 °F, low 34 °F 43°34° JanFebruary: average high 47 °F, low 36 °F 47°36° FebMarch: average high 53 °F, low 38 °F 53°38° MarApril: average high 59 °F, low 42 °F 59°42° AprMay: average high 67 °F, low 48 °F 67°48° MayJune: average high 72 °F, low 52 °F 72°52° JunJuly: average high 79 °F, low 57 °F 79°57° JulAugust: average high 80 °F, low 58 °F 80°58° AugSeptember: average high 74 °F, low 53 °F 74°53° SepOctober: average high 62 °F, low 47 °F 62°47° OctNovember: average high 50 °F, low 40 °F 50°40° NovDecember: average high 42 °F, low 35 °F 42°35° Dec

Precipitation by month inches · ❄ = snowfall

0″2″4″6″8″10″12″14″January: 11.31 in precipitation, 3.5 in snowfall 11.3❄4 JanFebruary: 8.67 in precipitation, 3.4 in snowfall 8.7❄3 FebMarch: 9.13 in precipitation, 0.3 in snowfall 9.1 MarApril: 6.47 in precipitation 6.5 AprMay: 4.08 in precipitation 4.1 MayJune: 3.21 in precipitation 3.2 JunJuly: 0.60 in precipitation 0.6 JulAugust: 0.90 in precipitation 0.9 AugSeptember: 2.62 in precipitation 2.6 SepOctober: 7.30 in precipitation 7.3 OctNovember: 12.48 in precipitation, 0.2 in snowfall 12.5 NovDecember: 13.45 in precipitation, 2.9 in snowfall 13.4❄3 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Bonneville Dam, OR (within 1 mile); precipitation: Bonneville Dam, OR (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

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

986488a
Stevenson, WA · 5 mi
970148a
Cascade Locks, OR · 9 mi
986108a
Carson, WA · 10 mi
970198b
Corbett, OR · 15 mi
986057b
Bingen, WA · 17 mi
970317b
Hood River, OR · 18 mi
970118a
Brightwood, OR · 18 mi
970497b
Rhododendron, OR · 19 mi

Washington planting zones →

Questions about 98639

What planting zone is ZIP code 98639?

ZIP code 98639 (North Bonneville, WA) is in USDA hardiness zone 9a on the 2023 map: the coldest night of an average winter reaches 20 to 25 °F (−6.7 to −3.9 °C).

When is the last frost in North Bonneville, WA?

The median last spring frost (32 °F) near 98639 is March 14; after April 4 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Bonneville Dam station.

When is the first frost in North Bonneville, WA?

The median first fall frost near 98639 is November 27, giving a median frost-free growing season of 257 days.

When should I plant tomatoes in 98639?

Start tomato seeds indoors around Jan 17 – Jan 31 and set transplants outside around Mar 21 – Apr 4, one to three weeks after the median last frost.

How much rain and snow does 98639 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 North Bonneville, WA?

The average high peaks at 80 °F in August, with about 11 days a year at 90 °F or more.

What kind of soil does 98639 have?

The USDA soil survey maps Pilchuck at the center of ZIP 98639: very fine sandy loam, somewhat excessively drained, pH about 6.1 (slightly acidic).

Did spring come early in North Bonneville, WA in 2026?

Spring leaf-out near 98639 came on Mar 2 in 2026, about the same as the 1991–2020 average (Mar 4), according to the USA National Phenology Network Spring Index.

What kind of onions grow in North Bonneville, WA?

Long-day onions: the longest day near 98639 is 15 h 42 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 98639 change?

Yes. The 2012 USDA map put 98639 in zone 8b; the 2023 map puts it in zone 9a. The newer map uses 1991–2020 data and more weather stations.