Climate Comfort Score
67/100
Good
2026 data Public-data reference. official source
30-year climate normals from 1 weather station (1991-2020).
Altona, Illinois has an average annual temperature of 49°F and a climate comfort score of 67/100 (Good). Annual precipitation totals 39.4". Based on NOAA 30-year normals (1991–2020).
Avg Temperature
49°F (9°C)
Avg High
60°F
Avg Low
38°F
Annual Precip
39.4"
Comfort Score
67/100
Good
Avg Annual Temperature
49°F
30-year mean (NOAA NCEI)
Annual Precipitation
39.4"
Liquid-equivalent total
Comfort score vs national 100-point ceiling (Altona) 67.0%
National median (≈55)
PlainClimate composite — temperature mildness, humidity, precipitation, extreme-weather frequency. Good for the Altona area.
Warming context for Altona
MethodologyHow the U.S. land temperature anomaly tracks against the global mean since 1900. The current NOAA 1991-2020 normal for Altona captures average conditions across the spread shown — the most recent decade is warmer than the 30-year mean.
- 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) | 1.8" | 29.4 | 0.0 |
| February | 35°F (2°C) | 16°F (-9°C) | 26°F (-4°C) | 2.1" | 26.7 | 0.0 |
| March | 48°F (9°C) | 27°F (-3°C) | 37°F (3°C) | 2.6" | 21.9 | 0.0 |
| April | 62°F (16°C) | 37°F (3°C) | 49°F (10°C) | 4.0" | 10.7 | 0.0 |
| May | 72°F (22°C) | 49°F (10°C) | 61°F (16°C) | 5.2" | 0.6 | 0.9 |
| June | 81°F (27°C) | 59°F (15°C) | 70°F (21°C) | 4.7" | 0.0 | 3.1 |
| July | 83°F (29°C) | 62°F (17°C) | 73°F (23°C) | 4.0" | 0.0 | 6.3 |
| August | 82°F (28°C) | 59°F (15°C) | 71°F (21°C) | 3.8" | 0.0 | 3.0 |
| September | 76°F (25°C) | 52°F (11°C) | 64°F (18°C) | 3.8" | 0.2 | 2.2 |
| October | 64°F (18°C) | 40°F (4°C) | 52°F (11°C) | 2.8" | 7.3 | 0.1 |
| November | 49°F (9°C) | 28°F (-2°C) | 38°F (3°C) | 2.6" | 19.6 | 0.0 |
| December | 35°F (2°C) | 19°F (-7°C) | 27°F (-3°C) | 2.1" | 27.6 | 0.0 |
Monthly Precipitation
Average monthly rainfall
January 1.8"
February 2.1"
March 2.6"
April 4.0"
May 5.2"
June 4.7"
July 4.0"
August 3.8"
September 3.8"
October 2.8"
November 2.6"
December 2.1"
Frost Dates & Growing Season
First Fall Freeze
October 12
50% probability date
Last Spring Freeze
April 28
50% probability date
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
6,534
Higher = more heating needed
Cooling Degree Days
744
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Related Data
PlainEnviro
EPA environmental data — pollution, water quality, and environmental health by location
PlainCarbon
Carbon emissions data — greenhouse gas reporting and facility-level CO2 data
PlainHazard
Natural disaster data — weather-related hazards, FEMA declarations, and risk profiles
PlainAirData
EPA air quality data — AQI readings, pollutant levels, and air quality trends
Climate Guides
Climate Insight: Altona, IL
The NOAA 1991–2020 climate normals describe Altona, Illinois as a location with an annual average temperature of 49°F, ranging from a mean daily high of 60°F to a mean daily low of 38°F. July is typically the warmest month of the year, while January is the coldest. These thirty-year averages, computed from station USC00110140, 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. Altona receives roughly 39.4 inches of precipitation each year, predominantly as rainfall. Growing-season length varies with elevation and microclimate, with the last spring freeze near April 28 and the first fall freeze near October 12. For energy use, 6,534 heating degree days and 744 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.
On PlainClimate's composite comfort index, Altona scores 67/100 (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 Altona, IL? ▼
The average annual temperature in Altona, Illinois is 49°F. The warmest month averages 83°F (29°C) and the coldest averages 13°F (-11°C).
How much rain does Altona get? ▼
Altona receives 39.4 inches of precipitation annually. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Altona? ▼
Altona has a climate comfort score of 67/100 (Good). This score considers temperature mildness, humidity, precipitation, and extreme weather frequency.
When is the growing season in Altona? ▼
Growing season data is not available for Altona.
How much energy does heating and cooling require in Altona? ▼
Altona has 6,534 heating degree days and 744 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 Altona 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 USC00110140. 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: USC00110140. 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
