Decatur, TN 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 Decatur's primary NOAA station, DECATUR 7NE.
The climate verdict for Decatur
Water is the standout signal in Decatur, Tennessee: 57.6 inches of precipitation in a normal year. Against that wet profile, NOAA records an annual average of 58°F. Its climate comfort score of 73/100 (good) lands mid-pack nationally, exceeding 66% of station-mapped location scores.
- 58°F
- average temperature, NOAA 1991-2020 normal
- 73/100
- comfort score, above 66% of station-mapped location scores
- 57.6"
- annual precipitation · 3" snow
- 200 days
- growing season, frost-free days
Decatur: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00402388 · Decatur, TN 58°F mean · 57.6" precip
TEMP-MILD · RANK-UPPER · PHOTO-FINISH · PRCP-WET · SWING-MID · COMF-MID · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-MILD 58°F
- RANK-UPPER #4,803
- PHOTO-FINISH ≈ Newkirk
- PRCP-WET 57.6"
- SWING-MID 40°F
- COMF-MID 73/100
- LOAD-HEAT 3,840 HDD
- STN-1 USC00402388
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Newkirk, NM (+ 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 TN station list.
- Decatur (this station) 58°F
- Cold Somerset, KY 58°F
- Hot Stony Creek, VA 58°F
- Near Newkirk, NM 58°F
- Near Kingston, TN 58°F
Climate Living Index · Decatur
Decatur: 64/100 · grade C
Decatur publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Decatur, not an official NOAA rating. Rankings still use Comfort Score 73/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Normal heat + freeze calendar | 85 calendar days | 81/100 · B |
| Snowfall burden | 3.3 inches/year | 73/100 · B |
| Annual temperature balance | 58.4°F · 9.1° from 67.5°F | 71/100 · B |
| Frost-free season | 200 days/year | 64/100 · C |
| Precipitation balance | 57.6 in · 22.6 from 35 in | 20/100 · F |
Decatur · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Decatur is a temperate Köppen climate: Cfa
Coldest-month mean 37.9°F and warmest-month mean 78.0°F place this station in temperate, no dry season, hot summer climates (Cfa). Class Cfa is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: temperate, specifically temperate, no dry season, hot summer.
- Köppen code
- Cfa
- Group
- Temperate
- Warmest month
- 78.0°F
- Coldest month
- 37.9°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 Decatur sits across the climate record
Three NOAA fields for Decatur's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Top 30% warmest
- Among 6,861 stations, Decatur sits in the warmer third of annual means.
- Annual precipitation
- Top 8% wettest
- Decatur's annual total ranks in the wetter third of 6,352 measured normals.
- Seasonal temperature swing
- 36th percentile swing
- Typical seasonal amplitude versus 6,861 complete station-years.
How Decatur compares across U.S. station-mapped locations
Decatur's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
73 Top 34% score exceeds 66% 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%). Below this entry.
- 60–70: 1,236 station-mapped locations (20%). Below this entry.
- 70–80: 650 station-mapped locations (11%). This entry sits in this band.
- 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 | 48°F (9°C) | 28°F (-2°C) | 38°F (3°C) | 5.6" | 0.9" | 22.4 | 0.0 |
| February | 53°F (11°C) | 30°F (-1°C) | 41°F (5°C) | 5.2" | 1.7" | 18.8 | 0.0 |
| March | 62°F (16°C) | 36°F (2°C) | 49°F (9°C) | 5.3" | 0.1" | 13.7 | 0.0 |
| April | 71°F (22°C) | 44°F (7°C) | 58°F (14°C) | 5.4" | 0.0" | 4.4 | 0.0 |
| May | 79°F (26°C) | 54°F (12°C) | 66°F (19°C) | 4.6" | 0.0" | 0.1 | 1.1 |
| June | 86°F (30°C) | 63°F (17°C) | 74°F (24°C) | 4.8" | 0.0" | 0.0 | 8.1 |
| July | 89°F (32°C) | 67°F (19°C) | 78°F (26°C) | 5.4" | 0.0" | 0.0 | 14.8 |
| August | 89°F (32°C) | 66°F (19°C) | 77°F (25°C) | 3.3" | 0.0" | 0.0 | 14.2 |
| September | 84°F (29°C) | 59°F (15°C) | 71°F (22°C) | 4.3" | 0.0" | 0.0 | 7.5 |
| October | 73°F (23°C) | 46°F (8°C) | 59°F (15°C) | 3.2" | 0.0" | 3.6 | 0.5 |
| November | 61°F (16°C) | 35°F (1°C) | 48°F (9°C) | 4.7" | 0.0" | 15.5 | 0.0 |
| December | 51°F (11°C) | 30°F (-1°C) | 41°F (5°C) | 5.7" | 0.6" | 20.2 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 90°F around July 26, short of 90°F on every date, while 85 dates carry a normal low at or below freezing, the coldest 27°F near January 17.
The freezing stretch
The normal low stays at or below 32°F into February 24, then returns to freezing around December 2, covering 85 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 July 3, when 41% of years recorded at least a hundredth of an inch. The driest is September 16 at 23%. Summed across the calendar, that is about 123 wet dates a year.
The widest day
October 28 carries the biggest normal gap between afternoon and dawn, 28°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Decatur.
Where Decatur Stands Nationally
This is one of the wettest normals climates ranked: about 58 inches of precipitation in a normal year, a total fewer than one station in ten surpasses.
Decatur 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: 0.9"
10.6 days with precipitation
Snow: 1.7"
11.4 days with precipitation
Snow: 0.1"
11.1 days with precipitation
10.6 days with precipitation
11.6 days with precipitation
11.4 days with precipitation
12.5 days with precipitation
9.6 days with precipitation
7.1 days with precipitation
7.8 days with precipitation
8.5 days with precipitation
Snow: 0.6"
11.0 days with precipitation
Decatur spreads its precipitation across the year
Neither half of the year dominates here: June through August take 23% of the annual total and December through February 29%, with neither reaching the 35% that would mark a distinct wet season. Decatur has no dry season to plan around, though it does carry a 40.1°F seasonal spread.
The gap between the wettest and driest month still matters: December averages 5.7" and October 3.2". The three wettest months together take 29% of the year, against the 25% a perfectly flat distribution would give them.
Shares are computed from this station's own 1991-2020 monthly precipitation normals. "Spread across the year" means neither the June-August nor the December-February share reaches 35%; it describes an average year, not the variability of any single one.
When it rains in Decatur, it arrives in quantity
57.6" of precipitation falls across only about 123 wet days here, averaging 0.47 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 123 a year, 34% of all days
- Average depth per wet day
- 0.47 inches
- Most wet days
- July, about 13
- Fewest wet days
- September, about 7
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.
Snow reaches Decatur, but rarely amounts to much
The normals record 3.3 inches of snow a year here, most likely in February. That is a real but marginal amount: enough that snow is part of the local record, not enough to define the winter.
A figure in this range usually reflects a handful of events that melt quickly rather than a season of accumulation; about 3 days a year record any measurable snow at all.
NOAA 1991-2020 normals. An average across thirty years can smooth away a single heavy winter, so a small annual figure does not mean a significant snowfall is impossible.
Frost Dates & Growing Season
First Fall Freeze
October 27
50% probability date
Last Spring Freeze
April 10
50% probability date
Growing Season
200 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
3,840
Higher = more heating needed
Cooling Degree Days
1,450
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside TN closest to Decatur 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 (58°F here).
- Camargo, OK 58°F · 0.0°F off
- Campo, CA 58°F · 0.0°F off
- Cornelia, GA 58°F · 0.0°F off
- Hardy, AR 58°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (57.6" here), excluding temperature-peer places.
- Minden, LA 57.6" · 0.0" off
- Muscle Shoals, AL 57.6" · 0.0" off
- Fordyce, AR 57.6" · 0.0" off
- Gadsden, AL 57.6" · 0.0" off
Data-derived climate profile
How Decatur's climate pattern fits together
heating led · wet · mid swing
Decatur's energy balance leans toward cold weather: 3,840 annual heating degree days against 1,450 for cooling. Its 40.1°F seasonal range still makes the monthly rows more useful than the annual average alone.
Decatur's frost-free season lasts about 200 days, a middle-length window whose endpoints matter more than the annual average. It describes freeze probability, not year-specific planting conditions.
July and January mark the typical warm and cold ends of the calendar in Decatur's middle-range seasonal profile. The measured spread is 40.1°F. The annual average is 58°F. Neither the annual mean nor one extreme month represents the full calendar on its own.
Alongside its heating load, Decatur carries 57.6 inches of precipitation in a normal year, inside PlainClimate's wet range. Annual snowfall totals 3.3 inches. That distinction matters because a wet annual total can arrive as rain, snow, or a mixture at different times.
These labels group NOAA 1991-2020 normals from Decatur's primary station, so the winter figures are a thirty-year average and not a floor: a single hard season can run well below them. Treat each band as a descriptive range for Decatur, not an official NOAA class or a year-ahead forecast.
Questions about Decatur's climate
How much rain does Decatur get? ▼
How many days above 90°F does Decatur get? ▼
How much energy does heating and cooling require in Decatur? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Decatur's primary station: DECATUR 7NE (USC00402388). 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 4719880). Match rule for Decatur: 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 Decatur 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.