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

Planting zone for 99785 — Brevig Mission, AK

ZIP code 99785 (Brevig Mission, Nome (CA) County) is in USDA zone 3a: the coldest winter night averages −40 to −35 °F. The median last spring frost is June 5 and the first fall frost September 3.

Where ZIP 99785 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.

Zone3a−40 to −35 °F

Coldest night−40 to −37.2 °C

Last frostJun 5

First frostSep 3

2012 zone3a

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 3a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Brevig Mission, AK…

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 Brevig Mission, AK

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostJune 5median — 50% chance of a later frost

Safe for tender plantsJune 26only 10% chance of frost after

First fall frostSeptember 3median — 10% chance by Aug 15

Growing season88 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 23 and returns around September 19.

From the NOAA station Nome Municipal Airport, AK — 65 miles away, elevation 13 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 99785

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 24 – May 8

SpinachSow outdoors · Apr 24 – May 15

Broccoli, cabbageStart indoors · Mar 27 – Apr 10

Broccoli, cabbageTransplant · May 15 – May 29

Onion setsPlant outdoors · May 8 – May 22

PotatoesPlant outdoors · May 15 – May 29

LettuceSow outdoors · May 8 – May 22

Carrots, beetsSow outdoors · May 15 – May 29

TomatoesStart indoors · Apr 10 – Apr 24

TomatoesTransplant · Jun 12 – Jun 26

Peppers, eggplantStart indoors · Mar 27 – Apr 10

Peppers, eggplantTransplant · Jun 19 – Jul 3

BeansSow outdoors · Jun 12 – Jun 26

Sweet cornSow outdoors · Jun 12 – Jun 26

Cucumbers, squashSow outdoors · Jun 12 – Jun 26

Fall lettuce, spinachSow outdoors · Jul 9 – Jul 23

GarlicPlant cloves · Aug 20 – Sep 24

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Jun 5) and first fall frost (Sep 3) 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.

Native plants for zone 3a in Alaska

80 plants native to Alaska, recorded in Alaska, and rated by the USDA to survive −40 °F or colder — the bottom of zone 3a. 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 Brevig Mission, AK.

Soil in Brevig Mission, AK

The soil mapped at the center of ZIP 99785 is E41-arctic tussock-scrub-silty frozen slopes — peat, very poorly drained.

TexturePeattop layer

DrainageVery poorly drainedconsider raised beds

Organic matter75%high

Hydrologic groupB/Dmoderate when drained; wet otherwise

Farmland classNot prime farmlandUSDA classification

Map unit: Seward Peninsula Highlands-Arctic Upland-Loess Plains.

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 99785; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Brevig Mission, AK

Summer high58 °Faverage high, July

Winter low−2 °Faverage low, January

Hot days0days a year at 90 °F or more

Freezing nights231nights a year at 32 °F or less

Growing degree days247base 50 °F — the season’s usable heat

Longest day22 h 34 mindaylight on June 21

Shortest day3 h 20 mindaylight on December 21

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

Average high and low, by month

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Nome Municipal Airport, AK (65 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

1 of the 3 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

997783a

Teller, AK · 8 mi

997723a

Shishmaref, AK · 38 mi

997833b

Wales, AK · 48 mi

Alaska planting zones →

Questions about 99785

What planting zone is ZIP code 99785?

ZIP code 99785 (Brevig Mission, AK) is in USDA hardiness zone 3a on the 2023 map: the coldest night of an average winter reaches −40 to −35 °F (−40 to −37.2 °C).

When is the last frost in Brevig Mission, AK?

The median last spring frost (32 °F) near 99785 is June 5; after June 26 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Nome Municipal Airport station.

When is the first frost in Brevig Mission, AK?

The median first fall frost near 99785 is September 3, giving a median frost-free growing season of 88 days.

When should I plant tomatoes in 99785?

Start tomato seeds indoors around Apr 10 – Apr 24 and set transplants outside around Jun 12 – Jun 26, one to three weeks after the median last frost.

How hot do summers get in Brevig Mission, AK?

The average high peaks at 58 °F in July, with about 0 days a year at 90 °F or more.

What kind of soil does 99785 have?

The USDA soil survey maps E41-arctic tussock-scrub-silty frozen slopes at the center of ZIP 99785: peat, very poorly drained.

What kind of onions grow in Brevig Mission, AK?

Long-day onions: the longest day near 99785 is 22 h 34 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).