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

Planting zone for 98939 — Parker, WA

ZIP code 98939 (Parker, Yakima County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 21 and the first fall frost October 15.

Where ZIP 98939 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.

Zone7a0 to 5 °F
Coldest night−17.8 to −15 °C
Last frostApr 21
First frostOct 15
2012 zone6b

Was 6b 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 7a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Parker, 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 Parker, WA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 21median — 50% chance of a later frost
Safe for tender plantsMay 7only 10% chance of frost after
First fall frostOctober 15median — 10% chance by Oct 4
Growing season176 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 31 and returns around October 26.

From the NOAA station Wapato, WA — 5 miles away, elevation 840 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 98939

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 10 – Mar 24
SpinachSow outdoors · Mar 10 – Mar 31
Broccoli, cabbageStart indoors · Feb 10 – Feb 24
Broccoli, cabbageTransplant · Mar 31 – Apr 14
Onion setsPlant outdoors · Mar 24 – Apr 7
PotatoesPlant outdoors · Mar 31 – Apr 14
LettuceSow outdoors · Mar 24 – Apr 7
Carrots, beetsSow outdoors · Mar 31 – Apr 14
TomatoesStart indoors · Feb 24 – Mar 10
TomatoesTransplant · Apr 28 – May 12
Peppers, eggplantStart indoors · Feb 10 – Feb 24
Peppers, eggplantTransplant · May 5 – May 19
BeansSow outdoors · Apr 28 – May 12
Sweet cornSow outdoors · Apr 28 – May 12
Cucumbers, squashSow outdoors · Apr 28 – May 12
Fall lettuce, spinachSow outdoors · Aug 20 – Sep 3
GarlicPlant cloves · Oct 1 – Nov 5
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 21) and first fall frost (Oct 15) 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 98939 came on Mar 16 — 3 days earlier than the 1991–2020 average (Mar 19).

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 7a in Washington

590 plants native to the lower 48 states, recorded in Washington, and rated by the USDA to survive 0 °F or colder — the bottom of zone 7a. Each links to its USDA PLANTS profile.

Trees 31

Shrubs 105

Wildflowers & perennials 282

Grasses 157

Vines 3

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 Parker, WA.

Soil in Parker, WA

The soil mapped at the center of ZIP 98939 is Esquatzel — silt loam, well drained.

TextureSilt loama good balance for most vegetables
pH7.0neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter1.5%low — add compost
Hydrologic groupBwater soaks in moderately
Farmland classPrime farmland if irrigatedUSDA classification

Map unit: Esquatzel silt loam, 0 to 2 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 98939; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Parker, WA

Summer high90 °Faverage high, July
Winter low23 °Faverage low, December
Hot days41days a year at 90 °F or more
Freezing nights127nights a year at 32 °F or less
Growing degree days3,018base 50 °F — the season’s usable heat
Longest day15 h 49 mindaylight on June 21
Shortest day8 h 34 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation7.8 inper year, rain and melted snow
Snowfall20 inper year

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 39 °F, low 24 °F 39°24° JanFebruary: average high 48 °F, low 26 °F 48°26° FebMarch: average high 57 °F, low 33 °F 57°33° MarApril: average high 65 °F, low 39 °F 65°39° AprMay: average high 75 °F, low 47 °F 75°47° MayJune: average high 81 °F, low 53 °F 81°53° JunJuly: average high 90 °F, low 59 °F 90°59° JulAugust: average high 89 °F, low 58 °F 89°58° AugSeptember: average high 80 °F, low 49 °F 80°49° SepOctober: average high 66 °F, low 37 °F 66°37° OctNovember: average high 50 °F, low 29 °F 50°29° NovDecember: average high 39 °F, low 23 °F 39°23° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″January: 1.10 in precipitation, 5.2 in snowfall 1.1❄5 JanFebruary: 0.61 in precipitation, 1.1 in snowfall 0.6❄1 FebMarch: 0.56 in precipitation, 0.3 in snowfall 0.6 MarApril: 0.56 in precipitation 0.6 AprMay: 0.83 in precipitation 0.8 MayJune: 0.54 in precipitation 0.5 JunJuly: 0.24 in precipitation 0.2 JulAugust: 0.23 in precipitation 0.2 AugSeptember: 0.23 in precipitation 0.2 SepOctober: 0.64 in precipitation, 0.2 in snowfall 0.6 OctNovember: 0.92 in precipitation, 1.6 in snowfall 0.9❄2 NovDecember: 1.36 in precipitation, 12 in snowfall 1.4❄12 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Wapato, WA (5 mi away); precipitation: Wapato, WA (5 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7a.

Washington planting zones →

Questions about 98939

What planting zone is ZIP code 98939?

ZIP code 98939 (Parker, WA) is in USDA hardiness zone 7a on the 2023 map: the coldest night of an average winter reaches 0 to 5 °F (−17.8 to −15 °C).

When is the last frost in Parker, WA?

The median last spring frost (32 °F) near 98939 is April 21; after May 7 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Wapato station.

When is the first frost in Parker, WA?

The median first fall frost near 98939 is October 15, giving a median frost-free growing season of 176 days.

When should I plant tomatoes in 98939?

Start tomato seeds indoors around Feb 24 – Mar 10 and set transplants outside around Apr 28 – May 12, one to three weeks after the median last frost.

How much rain and snow does 98939 get?

About 7.8 inches of precipitation a year and 20 inches of snowfall (NOAA 1991–2020 normals, Wapato station).

How hot do summers get in Parker, WA?

The average high peaks at 90 °F in July, with about 41 days a year at 90 °F or more.

What kind of soil does 98939 have?

The USDA soil survey maps Esquatzel at the center of ZIP 98939: silt loam, well drained, pH about 7.0 (neutral).

Did spring come early in Parker, WA in 2026?

Spring leaf-out near 98939 came on Mar 16 in 2026, 3 days earlier than the 1991–2020 average (Mar 19), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Parker, WA?

Long-day onions: the longest day near 98939 is 15 h 49 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 98939 change?

Yes. The 2012 USDA map put 98939 in zone 6b; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.