Climate · Oacoma

Oacoma, SD climate

Oacoma has cold, snowy winters and warm summers, with very little rain. A typical July afternoon reaches 88°, a January night drops to 10°, and about 43 inches of snow falls in a normal winter.

NOAA 1991-2020 climate normals Updated once a decade
July high
88°
120th hottest of 1,384 South Dakota towns
January low
10°
248th mildest of 1,384 South Dakota towns
Rain + melted snow
22 in
469th driest of 1,384 South Dakota towns
Snow a winter
43 in
473rd snowiest of 1,367 South Dakota towns
A normal year

What a year in Oacoma feels like

Winter

33° / 13°
Typical high / low · 16 days with an inch or more of snow

Spring

59° / 35°
Typical high / low · Last frost around May 1

Summer

85° / 60°
Typical high / low · 34 days reach 90° in a normal year

Fall

62° / 38°
Typical high / low · First frost around Oct 7
Best months to be outsideMayJunSepHighs of 62–84° and lows of 40° or more
Month by month

Oacoma weather by month

Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.

MonthHighLowRain + meltSnowWet daysSnow on ground30-yr range
January31°10°0.5" 7.3"618 12° – 36°
February35°14°0.7" 8.0"612 9° – 35°
March47°24°1.0" 7.2"610 24° – 50°
April59°34°2.5" 6.8"102 38° – 53°
May70°46°3.5" 0110 53° – 64°
June81°57°3.8" 0110 64° – 73°
July88°62°2.8" 090 66° – 82°
August86°60°2.6" 080 67° – 77°
September78°51°2.1" 070 58° – 70°
October62°37°1.8" 1.4"71 42° – 55°
November46°25°0.7" 5.1"55 24° – 45°
December34°14°0.5" 7.5"615 12° – 31°
Year60°36°22.5"43.3"9364

“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.

Rain & snow

Rain and snow in Oacoma

Oacoma gets 22 inches of rain and melted snow a year. June is the wettest month and January the driest. Rain or snow falls on about 93 days a year. Snow covers the ground about 64 days of the year.

22 in
Rain + melted snow a year
Less rain than 85% of U.S. towns
43 in
Snow in a normal winter
More snow than 74% of U.S. towns
64 days
With 1"+ of snow on the ground
More than 74% of U.S. towns

Rain + melted snow by month

Inches of water
3.8"

Snowfall by month

Inches of snow
8.0"
Frost & the growing season

About 158 frost-free days a year

In half of years the last 32° night comes by May 1 and the first one by October 7. That leaves about 158 frost-free days for gardens, shorter than 73% of U.S. towns.

156
nights at or below 32° in a normal year
18
nights below 0° in a normal year
34
days that reach 90° in a normal year

Freezing nights by month

Average nights at or below 32°

90° days by month

Average days at 90° or more
Heating & cooling

Heating and cooling a home in Oacoma

Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Oacoma, 89% of that work is heating and 11% is cooling, so the furnace matters far more than the air conditioner.

89%heating
6,983 heating degree daysMore heating than 73% of U.S. towns
895 cooling degree daysMore cooling than 54% of U.S. towns

Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.

Around Oacoma

Oacoma and its neighbors

Oacoma borders 5 towns with climate data. January nights across them vary by 2.2°. Oacoma has both the coldest January nights (9°) and the hottest July afternoons (89°). Oacoma’s January low is 10° and its July high 88°.

America: January low 11°, July high 88°Dixon: January low 12°, July high 88°Landing Creek: January low 11°, July high 88°Chamberlain: January low 10°, July high 88°Red Lake: January low 10°, July high 88°Union: January low 9°, July high 87°Pukwana: January low 9°, July high 87°Iona: January low 11°, July high 88°Oacoma: January low 9°, July high 89°Brule: January low 11°, July high 88°West Point: January low 10°, July high 87°Chamberlain: January low 10°, July high 88°Oacoma: January low 10°, July high 88° OacomaIonaOacomaBruleWest PointChamberlain
ColderMilder9° to 12°
Oacoma9.1° −1.2°
Chamberlain9.6° −0.7°
West Point9.8° −0.5°
Oacoma10.3°
Brule10.5° +0.2°
Iona11.3° +1.0°

Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.

Compared with other towns

How Oacoma compares

Summer heat88° July high
Hotter than 70% of U.S. towns120th hottest of 1,384 South Dakota towns
Winter cold10° January low
Colder than 81% of U.S. towns248th mildest of 1,384 South Dakota towns
Precipitation22" a year
Drier than 85% of U.S. towns469th driest of 1,384 South Dakota towns
Snow43" a winter
Snowier than 74% of U.S. towns473rd snowiest of 1,367 South Dakota towns
Growing season158 frost-free days
Shorter than 73% of U.S. towns174th longest of 1,383 South Dakota towns

Compared with every U.S. town and city on TownTapestry, each counted once.

Then and now

Warmer than it used to be

+1.2°1991–2020 average vs. the 20th century (1901–2000)

The last 30 years in Oacoma averaged 1.2° warmer than the 1900s. The biggest change is in January (+3.7°). The shift is larger than in 51% of U.S. towns.

❄️ Winter+3.0° now 23°, was 20°
🌷 Spring+0.8° now 47°, was 46°
☀️ Summer+0.2° now 72°, was 72°
🍂 Fall+0.8° now 50°, was 49°

Change by month1991–2020 average minus 1901–2000 average, at Oacoma’s spot on NOAA’s grid

Year to year

How much a month can swing

A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 9° to 35°. June is the most reliable, staying within 9°.

Coldest to warmest month in 30 yearsNormal
Questions

Common questions about Oacoma’s climate

What is the coldest month in Oacoma?

January, with a typical high of 31° and a low of 10°.

What is the hottest month in Oacoma?

July, with a typical high of 88° and a low of 62°. About 34 days a year reach 90°.

How much snow does Oacoma get?

About 43 inches in a normal winter, most of it in February.

When is the first frost in Oacoma?

In half of years the first 32° night comes by October 7, and the last spring frost by May 1.

What is the rainiest month in Oacoma?

June, with 3.8 inches of rain and melted snow. The year totals 22 inches.

Temperatures and rainfall come from NOAA’s gridded climate normals for Oacoma itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Chamberlain 5 S, SD (9 mi, snow) and Chamberlain Municipal Airport, SD (8 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.

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