PlainClimate
2026 data Public-data reference. official source

Knoxville, IL Climate

Temperature, precipitation, and comfort score from NOAA NCEI 1991-2020 normals →

30-year climate normals from 1 weather station (1991-2020).

Knoxville, Illinois has an average annual temperature of 50°F and a climate comfort score of 62/100 (Good). Annual precipitation totals 40.5", including 25.4" of snow. Based on NOAA 30-year normals (1991–2020).

Avg Temperature

50°F (10°C)

Avg High

60°F

Avg Low

41°F

Annual Precip

40.5"

Annual Snow

25.4"

Comfort Score

62/100

Good

Climate Comfort Score

62/100

Good

Avg Annual Temperature

50°F

30-year mean (NOAA NCEI)

Annual Precipitation

40.5"

Plus 25.4" of snow

Comfort score vs national 100-point ceiling (Knoxville) 62.0%
National median (≈55)

PlainClimate composite — temperature mildness, humidity, precipitation, extreme-weather frequency. Good for the Knoxville area.

Warming context for Knoxville

Methodology

How the U.S. land temperature anomaly tracks against the global mean since 1900. The current NOAA 1991-2020 normal for Knoxville captures average conditions across the spread shown — the most recent decade is warmer than the 30-year mean.

Warming context — U.S. vs global, with Paris reference lines Anomaly chart from 1900 to 2024. Local series shows warming of 0.11 °C per decade versus a global rate of 0.11 °C per decade (ratio 1.00). Paris Agreement thresholds at 1.5 and 2.0 °C are dashed. -1.0°C -0.5°C +0.0°C +0.5°C +1.0°C +1.5°C +2.0°C +2.5°C Paris 1.5°C Paris 2.0°C 1900192019401960198020002020
  • 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
Sources: NOAA NCEI, NASA GISTEMP. Paris thresholds per IPCC AR6 WG1.

Monthly Temperatures

Average daily high and low temperatures by month

Month Avg High Avg Low Mean
January 32°F (0°C) 14°F (-10°C) 23°F (-5°C)
February 36°F (2°C) 18°F (-8°C) 27°F (-3°C)
March 49°F (9°C) 29°F (-2°C) 39°F (4°C)
April 62°F (16°C) 39°F (4°C) 51°F (10°C)
May 72°F (22°C) 51°F (10°C) 61°F (16°C)
June 81°F (27°C) 61°F (16°C) 71°F (22°C)
July 84°F (29°C) 65°F (18°C) 74°F (23°C)
August 82°F (28°C) 63°F (17°C) 72°F (22°C)
September 76°F (25°C) 54°F (12°C) 65°F (19°C)
October 64°F (18°C) 42°F (5°C) 53°F (12°C)
November 49°F (10°C) 31°F (-1°C) 40°F (4°C)
December 36°F (2°C) 21°F (-6°C) 29°F (-2°C)

Monthly Precipitation

Average monthly rainfall and snowfall

January 2.1"

Snow: 6.4"

8.5 days with precipitation

February 2.1"

Snow: 7.7"

8.7 days with precipitation

March 2.6"

Snow: 3.4"

10.1 days with precipitation

April 4.0"

Snow: 0.4"

11.5 days with precipitation

May 5.5"

13.9 days with precipitation

June 4.6"

11.8 days with precipitation

July 4.2"

9.8 days with precipitation

August 3.5"

9.9 days with precipitation

September 4.2"

8.1 days with precipitation

October 3.0"

Snow: 0.2"

9.7 days with precipitation

November 2.5"

Snow: 1.4"

8.0 days with precipitation

December 2.2"

Snow: 5.9"

9.4 days with precipitation

Frost Dates & Growing Season

First Fall Freeze

October 20

50% probability date

Last Spring Freeze

April 21

50% probability date

Heating & Cooling Degree Days

Annual totals indicate energy demand for heating and cooling

Heating Degree Days

6,191

Higher = more heating needed

Cooling Degree Days

899

Higher = more cooling needed

Warmest Month

July

Coldest Month

January

Related Data

Climate Guides

Climate Insight: Knoxville, IL

The NOAA 1991–2020 climate normals describe Knoxville, Illinois as a location with an annual average temperature of 50°F, ranging from a mean daily high of 60°F to a mean daily low of 41°F. July is typically the warmest month of the year, while January is the coldest. These thirty-year averages, computed from station USC00114780, smooth out year-to-year variability and give a baseline expectation for typical conditions in any given month.

Precipitation patterns matter as much as temperature for anyone planning to live, garden, or travel here. Knoxville receives roughly 40.5 inches of precipitation each year, with 25.4 inches typically falling as snow. Growing-season length varies with elevation and microclimate, with the last spring freeze near April 21 and the first fall freeze near October 20. For energy use, 6,191 heating degree days and 899 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 62/100 (Good), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. Use the monthly tables above to plan around specific windows — shoulder seasons for mild highs and lows, peak summer for July-driven heat, or deep winter for January-driven cold. All figures here are thirty-year averages: any single year may run warmer, wetter, drier, or cooler than the normal, so treat them as planning guidance rather than forecasts.

Frequently Asked Questions

What is the average temperature in Knoxville, IL?
The average annual temperature in Knoxville, Illinois is 50°F. The warmest month averages 84°F (29°C) and the coldest averages 14°F (-10°C).
How much rain does Knoxville get?
Knoxville receives 40.5 inches of precipitation annually, including 25.4 inches of snow. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Knoxville?
Knoxville has a climate comfort score of 62/100 (Good). This score considers temperature mildness, humidity, precipitation, and extreme weather frequency.
When is the growing season in Knoxville?
Growing season data is not available for Knoxville.
How much energy does heating and cooling require in Knoxville?
Knoxville has 6,191 heating degree days and 899 cooling degree days annually. Higher heating degree days indicate greater winter energy demand, while higher cooling degree days indicate greater summer cooling needs.
Where does this Knoxville climate data come from?
All climate data comes from NOAA U.S. Climate Normals v1.0.1, covering the 30-year period from 1991 to 2020. Data is collected from weather station USC00114780. These 30-year averages are the standard reference for typical weather conditions.

Data Sources

Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). Station: USC00114780. For informational purposes only.

Related

Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainClimate Editorial