Swea City, IA Climate: Temperature & Rain by Month
Explore NOAA NCEI's 1991–2020 climate normals → and a clearly labeled PlainClimate comfort calculation
30-year climate normals (1991-2020) from Swea City's primary NOAA station, SWEA CITY 5N.
The climate verdict for Swea City
Winter sets the terms in Swea City, Iowa. A pronounced 57.1°F seasonal swing and heating demand above twice the cooling total frame an annual average of 44°F. At 49/100 (moderate) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 18% of scores.
- 44°F
- yearly average temperature, NOAA normal
- 49/100
- comfort score, above 18% of station-mapped location scores
- 32.9"
- annual precipitation · 40" snow
- 150 days
- frost-free days per growing season
Swea City: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00138026 · Swea City, IA 44°F mean · 32.9" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-MID · SWING-WIDE · COMF-LOW · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 44°F
- RANK-COOL #961
- PHOTO-FINISH ≈ Hoover
- PRCP-MID 32.9"
- SWING-WIDE 57°F
- COMF-LOW 49/100
- LOAD-HEAT 8,171 HDD
- STN-1 USC00138026
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Hoover, SD (+ 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 IA station list.
- Swea City (this station) 44°F
- Hot Zumbrota, MN 44°F
- Near Hoover, SD 44°F
- Near Wisconsin Rapids, WI 44°F
- Near Lakefield, MN 44°F
Climate Living Index · Swea City
Swea City: 35/100 · grade F
Swea City publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Swea City, not an official NOAA rating. Rankings still use Comfort Score 49/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Precipitation balance | 32.9 in · 2.1 from 35 in | 91/100 · A |
| Normal heat + freeze calendar | 174 calendar days | 29/100 · F |
| Snowfall burden | 39.7 inches/year | 28/100 · F |
| Frost-free season | 150 days/year | 25/100 · F |
| Annual temperature balance | 43.8°F · 23.7° from 67.5°F | 15/100 · F |
Swea City · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Swea City is a continental Köppen climate: Dfb
Coldest-month mean 13.2°F and warmest-month mean 70.3°F place this station in continental, no dry season, warm summer climates (Dfb). Class Dfb is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: continental, specifically continental, no dry season, warm summer.
- Köppen code
- Dfb
- Group
- Continental
- Warmest month
- 70.3°F
- Coldest month
- 13.2°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 Swea City sits across the climate record
Three NOAA fields for Swea City's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Cooler than 86%
- Among 6,861 stations, Swea City sits in the cooler third of annual means.
- Annual precipitation
- 44th percentile wetness
- Neither arid nor torrential versus 6,352 station totals.
- Seasonal temperature swing
- Wider than 95%
- Warmest-to-coldest month gap for Swea City is large versus 6,861 complete station-years.
How Swea City compares across U.S. station-mapped locations
Swea City's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
49 18th percentile score exceeds 18% 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%). This entry sits in this band.
- 50–60: 1,329 station-mapped locations (21%). Above this entry.
- 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
Swea City's measured station temperature trend
MethodologyAcross 33 complete annual observations from 1957 to 2022, SWEA CITY 5N changed little at a fitted rate of 0.01°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Swea City primary station fitted change +0.01 °C/decade
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 22°F (-6°C) | 5°F (-15°C) | 13°F (-10°C) | 0.9" | 10.9" | 31.0 | 0.0 |
| February | 27°F (-3°C) | 8°F (-13°C) | 18°F (-8°C) | 0.9" | 8.5" | 27.2 | 0.0 |
| March | 40°F (4°C) | 21°F (-6°C) | 31°F (-1°C) | 1.8" | 4.6" | 25.6 | 0.0 |
| April | 55°F (13°C) | 33°F (0°C) | 44°F (7°C) | 3.4" | 3.6" | 11.5 | 0.1 |
| May | 68°F (20°C) | 46°F (8°C) | 57°F (14°C) | 4.6" | 0.0" | 1.1 | 1.0 |
| June | 78°F (25°C) | 57°F (14°C) | 67°F (20°C) | 4.7" | 0.0" | 0.0 | 2.9 |
| July | 81°F (27°C) | 60°F (15°C) | 70°F (21°C) | 4.2" | 0.0" | 0.0 | 4.5 |
| August | 78°F (26°C) | 58°F (14°C) | 68°F (20°C) | 4.1" | 0.0" | 0.0 | 1.5 |
| September | 73°F (23°C) | 48°F (9°C) | 60°F (16°C) | 3.2" | 0.0" | 0.9 | 1.0 |
| October | 59°F (15°C) | 35°F (2°C) | 47°F (8°C) | 2.5" | 0.7" | 10.9 | 0.1 |
| November | 42°F (5°C) | 22°F (-5°C) | 32°F (0°C) | 1.5" | 3.1" | 24.2 | 0.0 |
| December | 28°F (-2°C) | 11°F (-12°C) | 19°F (-7°C) | 1.2" | 8.3" | 30.5 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 81°F around July 5, short of 90°F on every date, while 174 dates carry a normal low at or below freezing, the coldest 3°F near January 22.
The freezing stretch
The normal low stays at or below 32°F into April 14, then returns to freezing around October 24, covering 174 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 26, when 39% of years recorded at least a hundredth of an inch. The driest is February 2 at 18%. Summed across the calendar, that is about 93 wet dates a year.
The widest day
September 24 carries the biggest normal gap between afternoon and dawn, 26°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Swea City.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 10.9"
5.7 days with precipitation
Snow: 8.5"
5.1 days with precipitation
Snow: 4.6"
6.7 days with precipitation
Snow: 3.6"
9.8 days with precipitation
12.4 days with precipitation
10.9 days with precipitation
8.5 days with precipitation
7.6 days with precipitation
7.6 days with precipitation
Snow: 0.7"
7.1 days with precipitation
Snow: 3.1"
5.6 days with precipitation
Snow: 8.3"
6.0 days with precipitation
Swea City runs a summer-peaked wet season
39% of Swea City'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 4.7", on a wide 57.1°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 41% of the annual total between them.
- Driest month: January at 0.9".
- Winter share: 9% 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.
When it rains in Swea City, it arrives in quantity
32.9" of precipitation falls across only about 93 wet days here, averaging 0.35 inches each. Fewer days carry more water: the year's total is delivered in comparatively heavy events rather than persistent damp.
- Days with measurable precipitation
- about 93 a year, 25% of all days
- Average depth per wet day
- 0.35 inches
- Most wet days
- May, about 12
- Fewest wet days
- February, about 5
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year, and a per-day average is not a forecast of any individual storm.
Winter brings real snow to Swea City
Swea City averages 39.7 inches of snowfall a year, with January the snowiest month on the normals, spread across roughly 23 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: 39.7 inches of depth.
- Days recording measurable snow: about 23 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 12% 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 4
50% probability date
Growing Season
150 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
8,171
Higher = more heating needed
Cooling Degree Days
497
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside IA closest to Swea City 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 (44°F here).
- Bridgton, ME 44°F · 0.0°F off
- Buffalo, MN 44°F · 0.0°F off
- Choteau, MT 44°F · 0.0°F off
- Hamer, ID 44°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (32.9" here), excluding temperature-peer places.
- Flint, MI 32.9" · 0.0" off
- Northport, MI 32.9" · 0.0" off
- Bad Axe, MI 32.9" · 0.0" off
- Luck, WI 32.9" · 0.0" off
Snow and freeze rhythm
When cold and snow define Swea City
heating led · moderate · high swing
Winter and seasonal range jointly define this record. Swea City logs 8,171 heating degree days, more than twice its 497 cooling total, while the typical coldest-to-warmest-month gap reaches 57.1°F. The annual mean therefore compresses two materially different seasons.
Swea City's frost-free season lasts about 150 days, a middle-length window whose endpoints matter more than the annual average. It describes freeze probability, not year-specific planting conditions.
-
1. Swea City coldest normal
January
Averaging 13°F (-10°C), this month sits below freezing for the month as a whole, not merely overnight.
-
2. Swea City typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Swea City snow peak
January
Swea City averages 39.7 inches of snow a year, with January the snowiest month on the normals.
Questions about Swea City's climate
How much snow does Swea City get? ▼
How cold does Swea City get in winter? ▼
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Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Swea City's primary station: SWEA CITY 5N (USC00138026). 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 an incorporated place (GEOID 1976755). Match rule for Swea City: 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 Swea City 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.