Gann Valley, SD Climate: Temperature & Rain by Month
Average temperature and precipitation from NOAA NCEI 1991–2020 normals →, with a derived climate comfort score
30-year climate normals (1991-2020) from Gann Valley's primary NOAA station, GANN VALLEY 3 NNE - 2 stations mapped to the area.
The climate verdict for Gann Valley
Winter sets the terms in Gann Valley, South Dakota. A pronounced 58.9°F seasonal swing and heating demand above twice the cooling total frame an annual average of 45°F. Its climate comfort score of 59/100 (moderate) lands mid-pack nationally, exceeding 37% of station-mapped location scores.
- 45°F
- annual average temperature (NOAA normal)
- 59/100
- comfort score, above 37% of station-mapped location scores
- 22.7"
- annual precipitation · 41" snow
- 147 days
- growing season, frost-free days
Gann Valley: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00393211 · Gann Valley, SD 45°F mean · 22.7" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-DRY · SWING-WIDE · COMF-MID · LOAD-HEAT · STN-MULTI · BOOK-FULL
- TEMP-COOL 45°F
- RANK-COOL #1,372
- PHOTO-FINISH ≈ Hutchinson
- PRCP-DRY 22.7"
- SWING-WIDE 59°F
- COMF-MID 59/100
- LOAD-HEAT 7,912 HDD
- STN-MULTI USC00393211
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Hutchinson, MN (+ 0 °F mean)
Instrument codes from this station's NOAA 1991–2020 normals, mean temperature, corpus warmth rank, photo-finish peer station, precipitation band, seasonal swing, comfort composite, degree-day load, and field book, not a livability rating.
Mean-temperature neighbourhood
Nationwide NOAA normal poles and nearest peers, not a reprint of every SD station list.
- Gann Valley (this station) 45°F
- Cold Mobridge, SD 45°F
- Hot Hutchinson, MN 45°F
- Near Marshall, MN 45°F
- Near Enderlin, ND 45°F
Climate Living Index · Gann Valley
Gann Valley: 28/100 · grade F
Gann Valley publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Gann Valley, not an official NOAA rating. Rankings still use Comfort Score 59/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Precipitation balance | 22.7 in · 12.3 from 35 in | 57/100 · C |
| Snowfall burden | 40.9 inches/year | 27/100 · F |
| Frost-free season | 147 days/year | 23/100 · F |
| Normal heat + freeze calendar | 185 calendar days | 22/100 · F |
| Annual temperature balance | 45.2°F · 22.3° from 67.5°F | 20/100 · F |
Gann Valley · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Gann Valley is a continental Köppen climate: Dwa
Coldest-month mean 15.1°F and warmest-month mean 74.0°F place this station in continental, dry-winter, hot summer climates (Dwa). Class Dwa is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: continental, specifically continental, dry-winter, hot summer.
- Köppen code
- Dwa
- Group
- Continental
- Warmest month
- 74.0°F
- Coldest month
- 15.1°F
Source: official public datasets monthly normals (1991–2020) at the city’s primary station. This is a station classification, not a mapped regional consensus.
National standing · heating-led station
Where Gann Valley sits across the climate record
Three NOAA fields for Gann Valley's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Cooler than 80%
- Among 6,861 stations, Gann Valley sits in the cooler third of annual means.
- Annual precipitation
- 32nd percentile wetness
- Neither arid nor torrential versus 6,352 station totals.
- Seasonal temperature swing
- Wider than 97%
- Warmest-to-coldest month gap for Gann Valley is large versus 6,861 complete station-years.
How Gann Valley compares across U.S. station-mapped locations
Gann Valley's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
59 37th percentile score exceeds 37% of 6,189 station-mapped location scores
- 0–10: 0 station-mapped locations (0%). Below this entry.
- 10–20: 0 station-mapped locations (0%). Below this entry.
- 20–30: 96 station-mapped locations (2%). Below this entry.
- 30–40: 280 station-mapped locations (5%). Below this entry.
- 40–50: 1,113 station-mapped locations (18%). Below this entry.
- 50–60: 1,329 station-mapped locations (21%). This entry sits in this band.
- 60–70: 1,236 station-mapped locations (20%). Above this entry.
- 70–80: 650 station-mapped locations (11%). Above this entry.
- 80–90: 921 station-mapped locations (15%). Above this entry.
- 90–100: 564 station-mapped locations (9%). Above this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 27°F (-3°C) | 4°F (-16°C) | 15°F (-9°C) | 0.3" | 7.8" | 31.0 | 0.0 |
| February | 31°F (0°C) | 9°F (-13°C) | 20°F (-7°C) | 0.6" | 9.3" | 27.7 | 0.0 |
| March | 45°F (7°C) | 19°F (-7°C) | 32°F (0°C) | 1.0" | 4.6" | 27.0 | 0.0 |
| April | 58°F (14°C) | 31°F (0°C) | 44°F (7°C) | 1.7" | 5.4" | 16.2 | 0.1 |
| May | 70°F (21°C) | 44°F (7°C) | 57°F (14°C) | 3.4" | 0.0" | 3.3 | 1.0 |
| June | 80°F (26°C) | 56°F (13°C) | 68°F (20°C) | 4.2" | 0.0" | 0.0 | 4.8 |
| July | 87°F (31°C) | 61°F (16°C) | 74°F (23°C) | 3.2" | 0.0" | 0.0 | 12.0 |
| August | 85°F (29°C) | 58°F (15°C) | 72°F (22°C) | 2.9" | 0.0" | 0.0 | 6.7 |
| September | 77°F (25°C) | 48°F (9°C) | 62°F (17°C) | 2.8" | 0.0" | 1.0 | 3.2 |
| October | 61°F (16°C) | 32°F (0°C) | 47°F (8°C) | 1.6" | 1.8" | 15.0 | 0.2 |
| November | 45°F (7°C) | 20°F (-7°C) | 32°F (0°C) | 0.7" | 2.4" | 27.0 | 0.0 |
| December | 31°F (-1°C) | 10°F (-12°C) | 20°F (-7°C) | 0.3" | 9.6" | 30.9 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 89°F around July 22, short of 90°F on every date, while 185 dates carry a normal low at or below freezing, the coldest 3°F near January 13.
The freezing stretch
The normal low stays at or below 32°F into April 18, then returns to freezing around October 17, covering 185 dates in all.
Derived from the normal daily minimum. This is a different measure from the 50%-probability frost dates shown elsewhere on this page, which come from NOAA’s frost product.
Where the wet dates fall
The likeliest wet date is May 30, when 37% of years recorded at least a hundredth of an inch. The driest is November 15 at 13%. Summed across the calendar, that is about 86 wet dates a year.
The widest day
September 29 carries the biggest normal gap between afternoon and dawn, 30°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Gann Valley.
Where Gann Valley Stands Nationally
Freezing is routine here by normals standards — the normal low reaches 32°F or colder on about 185 nights a year, more than most ranked stations.
Gann Valley earns one nationally notable standing (outer quintile) against 6,860 NOAA 1991–2020 normals stations, middle-of-the-pack metrics stay silent here.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 7.8"
4.8 days with precipitation
Snow: 9.3"
5.4 days with precipitation
Snow: 4.6"
5.7 days with precipitation
Snow: 5.4"
8.9 days with precipitation
11.0 days with precipitation
10.8 days with precipitation
9.0 days with precipitation
8.8 days with precipitation
6.3 days with precipitation
Snow: 1.8"
5.8 days with precipitation
Snow: 2.4"
3.3 days with precipitation
Snow: 9.6"
6.3 days with precipitation
Gann Valley runs a summer-peaked wet season
46% of Gann Valley's yearly precipitation falls in June, July and August alone, against the 25% an evenly spread year would give those three months. The wettest month is June at 4.2", on a wide 58.9°F gap between its warmest and coldest month. Warm-season convection and, across the Southwest, the North American monsoon produce this shape: rain arrives in short heavy bursts during the hottest part of the year rather than as long cool-season soaking.
- Wettest three months: June, May, July, taking 47% of the annual total between them.
- Driest month: December at 0.3".
- Winter share: 6% falls in December, January and February.
Shares are computed from this station's own 1991-2020 monthly precipitation normals. A summer-peaked label means the June-August share reaches 35%; it describes timing across an average year, not any single season, and says nothing about how heavy an individual storm can be.
How Gann Valley's precipitation splits across the calendar
About 86 days a year record measurable precipitation here, carrying 22.7" between them, or roughly 0.26 inches on a typical wet day. That sits in the middle band: neither the many-light-days pattern of the Pacific Northwest and the Great Lakes, nor the few-heavy-events pattern of the Gulf and the desert Southwest.
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year and say nothing about the heaviest single storm on record.
Winter brings real snow to Gann Valley
Gann Valley averages 40.9 inches of snowfall a year, with December the snowiest month on the normals, spread across roughly 24 days that record measurable snow. That is depth accumulating on the ground, which is why it can exceed the annual precipitation figure: precipitation counts the liquid the snow melts down to, and fresh snow is mostly air.
- Annual snowfall: 40.9 inches of depth.
- Days recording measurable snow: about 24 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 18% of the year's precipitation.
NOAA 1991-2020 normals. The ten-to-one ratio is a convention, not a measurement: real ratios vary with temperature, so treat the share as an order of magnitude rather than an exact split.
Frost Dates & Growing Season
First Fall Freeze
October 1
50% probability date
Last Spring Freeze
May 7
50% probability date
Growing Season
147 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
7,912
Higher = more heating needed
Cooling Degree Days
745
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside SD closest to Gann Valley on two NOAA annual-normal axes (mean temperature and annual precipitation). Chip rows use distinct link sets.
Closest by average temperature
Nearest out-of-state peers by annual mean temperature (45°F here).
- Albert Lea, MN 45°F · 0.0°F off
- Brillion, WI 45°F · 0.0°F off
- Easton, WA 45°F · 0.0°F off
- Freeville, NY 45°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (22.7" here), excluding temperature-peer places.
- Clarendon, TX 22.7" · 0.0" off
- Red Lodge, MT 22.7" · 0.0" off
- Sonora, TX 22.7" · 0.0" off
- Hebbronville, TX 22.7" · 0.0" off
Snow and freeze rhythm
When cold and snow define Gann Valley
heating led · moderate · high swing
Winter and seasonal range jointly define this record. Gann Valley logs 7,912 heating degree days, more than twice its 745 cooling total, while the typical coldest-to-warmest-month gap reaches 58.9°F. The annual mean therefore compresses two materially different seasons.
Only about 147 days are frost-free in a normal year. That short interval is consistent with the cold-season signal, but the measure does not predict the exact first or last freeze in any one year.
-
1. Gann Valley coldest normal
January
Averaging 15°F (-9°C), this month sits below freezing for the month as a whole, not merely overnight.
-
2. Gann Valley typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Gann Valley snow peak
December
Gann Valley averages 40.9 inches of snow a year, with December the snowiest month on the normals.
Questions about Gann Valley's climate
How much snow does Gann Valley get? ▼
How cold does Gann Valley get in winter? ▼
How much energy does heating and cooling require in Gann Valley? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Gann Valley's primary station: GANN VALLEY 3 NNE (USC00393211). 2 NOAA stations are mapped to the Gann Valley area; the primary station's record is used for consistency. For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The 2024 Census Gazetteer identifies the exact name-and-state match as a census-designated place (GEOID 4623421), not an incorporated municipality. Match rule for Gann Valley: exact normalized name + state only, no fuzzy expansion, so nearby differently spelled facilities stay unmatched.
On this page every temperature, precipitation, and derived score for Gann Valley comes from its primary NOAA station record. No figure on this page is typed in by an editor - each value is rendered from NOAA 1991-2020 U.S. Climate Normals. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 1991–2020 normals.