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

Planting zone for 99791 — Atqasuk, AK

ZIP code 99791 (Atqasuk, North Slope County) is in USDA zone 2a: the coldest winter night averages −50 to −45 °F.

Where ZIP 99791 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.

Zone2a−50 to −45 °F
Coldest night−45.6 to −42.8 °C
Last frostrare
First frostrare
2012 zone1b

Was 1b 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 2a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Atqasuk, 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

No NOAA station with frost records lies within 90 miles of Atqasuk, AK, so we don't show frost dates here rather than guess. Your local extension office can give you a date.

Native plants for zone 2a in Alaska

44 plants native to Alaska, recorded in Alaska, and rated by the USDA to survive −50 °F or colder — the bottom of zone 2a. Each links to its USDA PLANTS profile.

Trees 8

balsam poplar80 ft · blooms late spring · high shade tolerance · to −79 °Fblack spruce65 ft · blooms late spring · low shade tolerance · to −79 °Flodgepole pine99 ft · blooms mid summer · high shade tolerance · to −70 °Fpaper birch70 ft · blooms mid spring · high shade tolerance · to −62 °Fquaking aspen65 ft · blooms mid spring · high shade tolerance · to −70 °Fsubalpine fir90 ft · blooms late spring · low shade tolerance · to −51 °F

Shrubs 16

alpine bearberry0.5 ft · blooms early spring · medium shade tolerance · to −62 °Fhalberd willow3 ft · blooms early summer · to −62 °FLapland rosebay3 ft · blooms late spring · low shade tolerance · to −62 °Flingonberry0.5 ft · blooms summer · high shade tolerance · to −62 °FMacKenzie's willow45 ft · blooms early spring · high shade tolerance · to −50 °Fmarsh Labrador tea0.5 ft · blooms summer · to −62 °F

Wildflowers & perennials 12

alpine sweetvetch2 ft · blooms early summer · high shade tolerance · to −62 °Farctic dock1 ft · blooms summer · high shade tolerance · to −62 °Farctic lupine2 ft · blooms spring · medium shade tolerance · to −62 °Farctic poppy1.5 ft · blooms summer · low shade tolerance · to −54 °Farctic raspberry1 ft · blooms summer · high shade tolerance · to −62 °Feightpetal mountain-avens0.3 ft · blooms late spring · medium shade tolerance · to −62 °F

Grasses 6

arctic bluegrass2 ft · high shade tolerance · to −62 °FHoppner's sedge1 ft · high shade tolerance · to −52 °Flargeflower speargrass2 ft · high shade tolerance · to −52 °Flivid sedge1 ft · blooms early summer · high shade tolerance · to −62 °FLyngbye's sedge1 ft · high shade tolerance · to −52 °FRamensk's sedge1 ft · high shade tolerance · to −52 °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 Atqasuk, AK.

Soil in Atqasuk, AK

The soil mapped at the center of ZIP 99791 is E46-Arctic sedge-loamy frozen low-center polygons — peat, very poorly drained.

TexturePeattop layer
pH5.0strongly acidic; most vegetables like 6.0–7.0
DrainageVery poorly drainedconsider raised beds
Organic matter90%high
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Arctic Coastal Plain-Arctic Lowland-Coastal Plains, High.

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 99791; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Atqasuk, AK

Summer high48 °Faverage high, July
Winter low−18 °Faverage low, January
Hot days0days a year at 90 °F or more
Freezing nights300nights a year at 32 °F or less
Growing degree days17base 50 °F — the season’s usable heat
Longest day24 h 00 mindaylight on June 21
Shortest day0 h 00 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation5.4 inper year, rain and melted snow
Snowfall46 inper year; 238 days with snow on the ground

Average high and low, by month

−30°−20°−10°0°10°20°30°40°50°60°32 °FJanuary: average high -5 °F, low -18 °F −5°−18° JanFebruary: average high -5 °F, low -18 °F −5°−18° FebMarch: average high -4 °F, low -17 °F −4°−17° MarApril: average high 11 °F, low -2 °F 11°−2° AprMay: average high 27 °F, low 19 °F 27°19° MayJune: average high 41 °F, low 31 °F 41°31° JunJuly: average high 48 °F, low 36 °F 48°36° JulAugust: average high 45 °F, low 35 °F 45°35° AugSeptember: average high 37 °F, low 30 °F 37°30° SepOctober: average high 26 °F, low 17 °F 26°17° OctNovember: average high 12 °F, low 0 °F 12°0° NovDecember: average high 0 °F, low -12 °F 0°−12° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″January: 0.14 in precipitation, 3.5 in snowfall 0.1❄4 JanFebruary: 0.21 in precipitation, 3.5 in snowfall 0.2❄4 FebMarch: 0.18 in precipitation, 2.9 in snowfall 0.2❄3 MarApril: 0.18 in precipitation, 3.6 in snowfall 0.2❄4 AprMay: 0.28 in precipitation, 3.4 in snowfall 0.3❄3 MayJune: 0.43 in precipitation, 0.7 in snowfall 0.4❄1 JunJuly: 0.98 in precipitation, 0.2 in snowfall 1.0 JulAugust: 1.09 in precipitation, 0.8 in snowfall 1.1❄1 AugSeptember: 0.77 in precipitation, 4.1 in snowfall 0.8❄4 SepOctober: 0.54 in precipitation, 10.3 in snowfall 0.5❄10 OctNovember: 0.37 in precipitation, 7.8 in snowfall 0.4❄8 NovDecember: 0.22 in precipitation, 5 in snowfall 0.2❄5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Barrow Post Rogers Airport, AK (57 mi away); precipitation: Barrow Post Rogers Airport, AK (57 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

997232b
Barrow, AK · 56 mi

Alaska planting zones →

Questions about 99791

What planting zone is ZIP code 99791?

ZIP code 99791 (Atqasuk, AK) is in USDA hardiness zone 2a on the 2023 map: the coldest night of an average winter reaches −50 to −45 °F (−45.6 to −42.8 °C).

How much rain and snow does 99791 get?

About 5.4 inches of precipitation a year and 46 inches of snowfall (NOAA 1991–2020 normals, Barrow Post Rogers Airport station).

How hot do summers get in Atqasuk, AK?

The average high peaks at 48 °F in July, with about 0 days a year at 90 °F or more.

What kind of soil does 99791 have?

The USDA soil survey maps E46-Arctic sedge-loamy frozen low-center polygons at the center of ZIP 99791: peat, very poorly drained, pH about 5.0 (strongly acidic).

What kind of onions grow in Atqasuk, AK?

Long-day onions: the longest day near 99791 is 24 h 00 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 99791 change?

Yes. The 2012 USDA map put 99791 in zone 1b; the 2023 map puts it in zone 2a. The newer map uses 1991–2020 data and more weather stations.