Smithville, Tennessee climate: Normal weather by month, frost dates and records
Smithville's normal year runs from 26°F January nights to 88°F July afternoons, with 57.0 inches of precipitation and 3 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 13.8°C, January lows of −4°C, July highs of 31°C, 1,447 mm of precipitation a year.
- NOAA stationSmithville (2 mi SE)
- Station IDUSC00408405
- Location35.94°N 85.79°W
- Elevation890 ft (271 m)
- Population5,546
On October 22, the normal high in Smithville is 70°F and the normal low 41°F, and the chance of measurable rain or snow is 32%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Smithville.
- Jan 47° 26°
- Feb 52° 28°
- Mar 60° 35°
- Apr 70° 42°
- May 78° 53°
- Jun 85° 61°
- Jul 88° 66°
- Aug 87° 64°
- Sep 82° 56°
- Oct 72° 43°
- Nov 60° 33°
- Dec 51° 28°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Smithville each month?
July is the warmest month, with normal highs of 88°F; January the coldest, with normal lows of 26°F. The most precipitation falls in March (5.73 in), the least in October (3.28 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 47°F | 26°F | 36.4°F | 4.92 | 1.1 | 14 | <1 | 23 | 10 h |
| February | 52°F | 28°F | 39.8°F | 5.07 | 1.1 | 13 | <1 | 20 | 10 h 50 min |
| March | 60°F | 35°F | 47.4°F | 5.73 | 0.3 | 13 | <1 | 14 | 11 h 50 min |
| April | 70°F | 42°F | 56.2°F | 4.99 | 0.0 | 12 | <1 | 5 | 13 h |
| May | 78°F | 53°F | 65.2°F | 4.87 | 0.0 | 13 | <1 | <1 | 14 h |
| June | 85°F | 61°F | 73.0°F | 5.14 | 0.0 | 12 | 5 | <1 | 14 h 30 min |
| July | 88°F | 66°F | 76.6°F | 5.18 | 0.0 | 12 | 9 | <1 | 14 h 20 min |
| August | 87°F | 64°F | 75.4°F | 3.92 | 0.0 | 10 | 9 | <1 | 13 h 30 min |
| September | 82°F | 56°F | 69.0°F | 4.03 | 0.0 | 9 | 3 | <1 | 12 h 30 min |
| October | 72°F | 43°F | 57.5°F | 3.28 | 0.0 | 10 | <1 | 4 | 11 h 20 min |
| November | 60°F | 33°F | 46.7°F | 4.15 | 0.0 | 10 | <1 | 16 | 10 h 20 min |
| December | 51°F | 28°F | 39.7°F | 5.69 | 0.6 | 14 | <1 | 21 | 9 h 40 min |
| Year (annual) | 69°F | 45°F | 56.9°F | 56.97 | 3.1 | 140 | 27 | 102 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 8°C | −4°C | 2.4°C | 125 mm | 3 cm |
| February | 11°C | −2°C | 4.3°C | 129 mm | 3 cm |
| March | 16°C | 1°C | 8.6°C | 146 mm | 1 cm |
| April | 21°C | 6°C | 13.4°C | 127 mm | 0 cm |
| May | 26°C | 11°C | 18.4°C | 124 mm | 0 cm |
| June | 29°C | 16°C | 22.8°C | 131 mm | 0 cm |
| July | 31°C | 19°C | 24.8°C | 132 mm | 0 cm |
| August | 31°C | 18°C | 24.1°C | 100 mm | 0 cm |
| September | 28°C | 13°C | 20.6°C | 102 mm | 0 cm |
| October | 22°C | 6°C | 14.2°C | 83 mm | 0 cm |
| November | 16°C | 1°C | 8.2°C | 105 mm | 0 cm |
| December | 11°C | −2°C | 4.3°C | 145 mm | 2 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00408405; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Smithville?
Normal highs sit between 65°F and 85°F in April, May, June, September and October. Of those, September has the fewest days with rain (9).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00408405.
When is the last frost in Smithville?
In Smithville, the last spring frost (32°F) comes after April 18 in half of years and after May 2 in one year in ten; the first autumn frost comes before October 22 in half of years and before October 10 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- April 181 year in 10 after May 2; 9 in 10 after April 2
- First autumn frost, half of years before
- October 221 year in 10 before October 10; 9 in 10 before November 4
NOAA puts the median frost-free season at 187 days, and the season without a hard freeze (28°F) at 209 days.
A hard freeze (28°F) comes after April 4 in half of springs and before November 1 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Smithville in zone 7b in ZIP code 37166, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Smithville's NOAA station is in zone 7a: the coldest night of a typical year reaches 4°F (29 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in Tennessee · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00408405; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get in Smithville?
In a normal year in Smithville, 27 days a year reach 90°F, 102 nights fall to 32°F or colder and 140 days bring measurable precipitation.
- Days at 90°F or more
- 27a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 102a normal year
- Days that stay below freezing
- 9high of 32°F or less
- Days with 0.01 inch of precipitation
- 140a normal year
- Days with 1 inch of snow or more
- 1a normal year
The highest temperature in this station's record (since 1971) is 105°F, on June 30, 2012; the lowest is −17°F, on February 5, 1996.
The wettest calendar year on that record is 2018, with 70.37 in; the snowiest season is 1976–77, with 10.6 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00408405; records: ACIS (NOAA Regional Climate Centers), station USC00408405. Records use complete months only; a month missing more than three days is left out.
How sunny is Smithville?
Over a year 74% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Smithville, 4.3 kWh per square metre a day. August is the sunniest month (79%) and February the cloudiest (62%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 66% | 2.3 |
| February | 62% | 2.9 |
| March | 68% | 4.0 |
| April | 74% | 5.3 |
| May | 75% | 5.8 |
| June | 79% | 6.3 |
| July | 78% | 6.0 |
| August | 79% | 5.5 |
| September | 78% | 4.8 |
| October | 76% | 3.7 |
| November | 74% | 2.8 |
| December | 65% | 2.0 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Smithville need?
A normal year in Smithville brings 4,148 heating degree days, 23% fewer than the median U.S. place (5,373), and 1,231 cooling degree days, 36% more than the median (908). Five months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 4,066 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 888 | 0 |
| February | 705 | 0 |
| March | 548 | 2 |
| April | 278 | 16 |
| May | 88 | 95 |
| June | 7 | 248 |
| July | 0 | 360 |
| August | 1 | 324 |
| September | 38 | 160 |
| October | 256 | 25 |
| November | 552 | 2 |
| December | 786 | 0 |
| Year (annual) | 4,148 | 1,231 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00408405. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Smithville been warmer than normal lately?
2021 averaged 57.4°F, 0.5°F above the 1991-2020 normal of 56.9°F.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 57.4°F | +0.5°F | 60.90 | – |
Over 34 complete years from 1972 to 2021, the station's annual mean temperature rose at a fitted 5.4°F per century (+0.30°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00408405; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Smithville's climate compare?
Smithville is warmer than 24 of the other 115 places with their own NOAA record in Tennessee, and wetter than 67. Across the 7,247 U.S. stations with normals, its annual mean of 56.9°F is warmer than 66%.
In the Köppen classification computed from these normals, Smithville is Cfa: temperate, no dry season, hot summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Questions about Smithville's climate
What is the coldest month in Smithville?
January, with a normal high of 47°F and a normal low of 26°F. The warmest is July (88°F by day, 66°F at night).
Does it snow in Smithville?
Yes: 3 inches in a normal year, falling on 3 days with 0.1 inch or more, the most in January (1.1 inches).
What is the rainiest month in Smithville?
March, with 5.73 in of precipitation in a normal year; the driest is October with 3.28 in.
What plant hardiness zone is Smithville in?
The USDA's 2023 map puts Smithville in zone 7b in ZIP code 37166, the nearest ZIP area. By the same method at Smithville's NOAA station, the coldest night of a typical year reaches 4°F (29 years, 1991-2020): zone 7a.
How late can frost come in Smithville?
In half of years the last 32°F night comes after April 18; in one year in ten it comes after May 2. Waiting until May 2 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Tennessee climateThe statewide normals and every place in the state
- Lancaster Edgar Evins Marina, TN10 miles from this station, 59.4°F a year
- Rock Island State Park, TN12 miles from this station, 58.8°F a year
- Sparta, TN18 miles from this station, 58.0°F a year
- Woodbury, TN18 miles from this station, 58.4°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made