Climate Comfort Score
68/100
Good
NOAA 1991–2020 normals 50°F annual avg Public-domain federal data
Knoxville, IA Climate
Temperature, precipitation, and comfort score from NOAA NCEI 1991–2020 normals →
- 50°F
- Avg annual temp
- 68/100
- Comfort score
- 37.5"
- Annual precip
- 182d
- Growing season
30-year climate normals from 1 weather station (1991-2020).
The climate verdict for Knoxville
Knoxville, Iowa averages 50°F a year and scores 68/100 on the comfort index - good, milder than 58% of U.S. cities.
- 50°F
- average temperature, NOAA 1991-2020 normal
- 68/100
- comfort score, milder than 58% of U.S. cities
- 37.5"
- precipitation, annual total
- 182 days
- growing season, frost-free days
Based on NOAA U.S. Climate Normals (1991–2020) - 30-year averages describing the typical year, not a forecast.
Avg Temperature
50°F (10°C)
Avg High
60°F
Avg Low
40°F
Annual Precip
37.5"
Comfort Score
68/100
Good
Avg Annual Temperature
50°F
30-year mean (NOAA NCEI)
Annual Precipitation
37.5"
Liquid-equivalent total
Comfort score vs national 100-point ceiling (Knoxville) 68.0%
National median (63)
PlainClimate composite, temperature mildness, humidity, precipitation, extreme-weather frequency. Good for the Knoxville area.
How Knoxville compares to every U.S. city
Knoxville's comfort score vs. all U.S. cities
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
68 Top 42% higher than 58% of 6,915 US cities
Each bar is a band; taller bars hold more US cities. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Warming context for Knoxville
MethodologyZooming out from Knoxville's own normal, the chart below shows how the U.S. land temperature anomaly has tracked the global mean since 1900 - the most recent decade sits warmer than the 30-year mean shown here.
- United States land mean (NOAA NCEI) +0.11 °C/decade
- Global anomaly (NASA GISTEMP) +0.11 °C/decade
- Paris Agreement thresholds 1.5°C / 2.0°C
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|
| January | 30°F (-1°C) | 13°F (-11°C) | 21°F (-6°C) | 1.1" | 29.8 | 0.0 |
| February | 35°F (2°C) | 17°F (-8°C) | 26°F (-3°C) | 1.7" | 25.1 | 0.0 |
| March | 48°F (9°C) | 28°F (-2°C) | 38°F (3°C) | 1.9" | 21.0 | 0.0 |
| April | 61°F (16°C) | 39°F (4°C) | 50°F (10°C) | 3.9" | 6.5 | 0.0 |
| May | 71°F (22°C) | 51°F (11°C) | 61°F (16°C) | 5.0" | 0.3 | 0.5 |
| June | 81°F (27°C) | 61°F (16°C) | 71°F (22°C) | 5.6" | 0.0 | 3.4 |
| July | 85°F (29°C) | 66°F (19°C) | 75°F (24°C) | 4.3" | 0.0 | 8.3 |
| August | 83°F (28°C) | 63°F (17°C) | 73°F (23°C) | 3.9" | 0.0 | 5.6 |
| September | 76°F (25°C) | 54°F (12°C) | 65°F (19°C) | 3.7" | 0.1 | 2.2 |
| October | 63°F (17°C) | 42°F (6°C) | 53°F (11°C) | 3.1" | 4.6 | 0.0 |
| November | 48°F (9°C) | 30°F (-1°C) | 39°F (4°C) | 1.8" | 17.6 | 0.0 |
| December | 36°F (2°C) | 19°F (-7°C) | 27°F (-3°C) | 1.6" | 28.1 | 0.0 |
Monthly Precipitation
Average monthly rainfall
January 1.1"
4.9 days with precipitation
February 1.7"
5.4 days with precipitation
March 1.9"
7.9 days with precipitation
April 3.9"
10.1 days with precipitation
May 5.0"
12.3 days with precipitation
June 5.6"
11.0 days with precipitation
July 4.3"
7.8 days with precipitation
August 3.9"
8.7 days with precipitation
September 3.7"
7.8 days with precipitation
October 3.1"
7.9 days with precipitation
November 1.8"
6.3 days with precipitation
December 1.6"
5.0 days with precipitation
Frost Dates & Growing Season
First Fall Freeze
October 19
50% probability date
Last Spring Freeze
April 20
50% probability date
Growing Season
182 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
6,415
Higher = more heating needed
Cooling Degree Days
950
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
What Knoxville's climate means for you
Knoxville runs 50°F a year - peaking in July, coldest in January.
- Gardeners get about 182 frost-free days, with the last spring freeze near April 20 - plan the planting calendar around it, not the regional average.
- Energy bills track 6,415 heating and 950 cooling degree days a year, higher means the furnace or AC runs more.
- Comparing places to live? Line this city up against nearby cities and the national rankings. See rankings
These are 30-year NOAA normals (1991–2020) - the typical year, not a forecast for any specific season.
Climate Guides
Climate Insight: Knoxville, IA
Knoxville, Iowa runs an annual average of 50°F, ranging from a mean daily high of 60°F to a mean daily low of 40°F, per NOAA's 1991–2020 climate normals. July is typically the warmest month of the year, while January is the coldest. Drawn from station USC00134502, these thirty-year averages smooth out year-to-year swings into a baseline for what a typical month looks like here.
Rainfall (and snow, where it falls) shapes day-to-day life here as much as temperature does. Knoxville sees about 37.5 inches of precipitation a year, predominantly as rainfall. The frost-free season averages 182 days, which directly shapes the planting calendar and growing potential for the area, with the last spring freeze near April 20 and the first fall freeze near October 19. On the energy side, 6,415 heating degree days and 950 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.
On PlainClimate's composite comfort index, Knoxville scores 68/100 (Good), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. The monthly tables above are the practical planning tool: mild highs and lows land in the shoulder seasons, July-driven heat peaks in summer, and January-driven cold sets in over deep winter. These are thirty-year averages, not a forecast - any single year can run warmer, wetter, drier, or cooler than the normal.
Frequently Asked Questions
What is the average temperature in Knoxville, IA? ▼
The average annual temperature in Knoxville, Iowa is 50°F. The warmest month averages 85°F (29°C) and the coldest averages 13°F (-11°C).
How much rain does Knoxville get? ▼
Knoxville receives 37.5 inches of precipitation annually. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Knoxville? ▼
Knoxville has a climate comfort score of 68/100 (Good), milder than 58% of U.S. cities in the PlainClimate database.
When is the growing season in Knoxville? ▼
Knoxville has approximately 182 frost-free days per year, with the last spring freeze around April 20 and the first fall freeze around October 19.
How much energy does heating and cooling require in Knoxville? ▼
Knoxville has 6,415 heating degree days and 950 cooling degree days annually, a heating-dominated climate. See our <a href="/guides/reading-weather-data/" class="underline hover:text-brand-600">guide to reading weather data</a> for what these figures mean.
Where does this Knoxville climate data come from? ▼
NOAA U.S. Climate Normals v1.0.1 (1991-2020), from weather station USC00134502 near Knoxville.
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). Station: USC00134502. For informational purposes only.
Read our methodology - how this data is sourced, computed, and verified.
Related
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainClimate Editorial
Every figure on PlainClimate is rendered directly from NOAA 1991-2020 U.S. Climate Normals data, no number is typed in by an editor. This page draws directly on NOAA 1991-2020 U.S. Climate Normals data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.