Altona, IL Climate: Temperature & Rain by Month
Pulled from NOAA NCEI 1991–2020 normals →: climate measurements used in PlainClimate's documented score
30-year climate normals (1991-2020) from Altona's primary NOAA station, ALTONA.
The climate verdict for Altona
Altona, Illinois has a mixed annual climate rather than one dominant extreme. Its NOAA normal shows an annual average of 49°F. Its climate comfort score of 64/100 (good) lands mid-pack nationally, exceeding 49% of station-mapped location scores.
- 49°F
- average temperature, NOAA 1991-2020 normal
- 64/100
- comfort score, above 49% of station-mapped location scores
- 39.4"
- yearly precipitation total
- 167 days
- frost-free days per growing season
Altona: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00110140 · Altona, IL 49°F mean · 39.4" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-MID · SWING-WIDE · COMF-MID · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 49°F
- RANK-COOL #2,470
- PHOTO-FINISH ≈ Scottsbluff
- PRCP-MID 39.4"
- SWING-WIDE 51°F
- COMF-MID 64/100
- LOAD-HEAT 6,534 HDD
- STN-1 USC00110140
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Scottsbluff, NE (+ 0.1 °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 IL station list.
- Altona (this station) 49°F
- Cold Lodgepole NO, NE 49°F
- Hot Tully Lake, MA 49°F
- Near Scottsbluff, NE 49°F
- Near Saint Johns, MI 49°F
Climate Living Index · Altona
Altona: 50/100 · grade D
Altona publishes 4 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 2 missing weights rescale to 100.
PlainClimate-derived for Altona, not an official NOAA rating. Rankings still use Comfort Score 64/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Precipitation balance | 39.4 in · 4.4 from 35 in | 84/100 · B |
| Normal heat + freeze calendar | 149 calendar days | 47/100 · D |
| Frost-free season | 167 days/year | 39/100 · F |
| Annual temperature balance | 49.0°F · 18.5° from 67.5°F | 36/100 · F |
Altona · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Altona is a continental Köppen climate: Dfa
Coldest-month mean 21.4°F and warmest-month mean 72.6°F place this station in continental, no dry season, hot summer climates (Dfa). Class Dfa is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: continental, specifically continental, no dry season, hot summer.
- Köppen code
- Dfa
- Group
- Continental
- Warmest month
- 72.6°F
- Coldest month
- 21.4°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 Altona sits across the climate record
Three NOAA fields for Altona's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- 36th percentile warmth
- Mid-pack annual mean versus 6,861 station normals.
- Annual precipitation
- 57th percentile wetness
- Neither arid nor torrential versus 6,352 station totals.
- Seasonal temperature swing
- Wider than 84%
- Warmest-to-coldest month gap for Altona is large versus 6,861 complete station-years.
How Altona compares across U.S. station-mapped locations
Altona's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
64 49th percentile score exceeds 49% 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%). This entry sits in this band.
- 70–80: 650 station-mapped locations (11%). Above this entry.
- 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 | 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 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 84°F around July 12, short of 90°F on every date, while 149 dates carry a normal low at or below freezing, the coldest 12°F near January 23.
The freezing stretch
The normal low stays at or below 32°F into April 1, then returns to freezing around November 5, covering 149 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.
The widest day
September 23 carries the biggest normal gap between afternoon and dawn, 25°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Altona.
Monthly Precipitation
Average monthly rainfall
Altona spreads its precipitation across the year
Neither half of the year dominates here: June through August take 32% of the annual total and December through February 15%, with neither reaching the 35% that would mark a distinct wet season. Altona has no dry season to plan around, though it does carry a wide 51.2°F gap between its warmest and coldest month.
The gap between the wettest and driest month still matters: May averages 5.2" and January 1.8". The three wettest months together take 35% 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.
Frost Dates & Growing Season
First Fall Freeze
October 12
50% probability date
Last Spring Freeze
April 28
50% probability date
Growing Season
167 days
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
Nationwide similar cities
Other rankable U.S. places outside IL closest to Altona 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 (49°F here).
- Burney, CA 49°F · 0.0°F off
- Cairo, NY 49°F · 0.0°F off
- Condon, OR 49°F · 0.0°F off
- Danville, OH 49°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (39.4" here), excluding temperature-peer places.
- Grand Rapids, MI 39.4" · 0.0" off
- Lawrence, KS 39.4" · 0.0" off
- Fort Madison, IA 39.4" · 0.0" off
- Meeker, OK 39.4" · 0.0" off
Data-derived climate profile
How Altona's climate pattern fits together
heating led · moderate · mid swing
Altona's energy balance leans toward cold weather: 6,534 annual heating degree days against 744 for cooling. Its 51.2°F seasonal range still makes the monthly rows more useful than the annual average alone.
Altona's frost-free season lasts about 167 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 Altona's middle-range seasonal profile. The measured spread is 51.2°F. The annual average is 49°F. Neither the annual mean nor one extreme month represents the full calendar on its own.
Altona's 39.4 inches of annual precipitation falls in PlainClimate's middle band, so “wet” or “dry” is not the leading description. Snowfall is not added to the interpretation because its annual value is missing. Temperature balance and the calendar distribution carry more information than the annual moisture label alone.
These labels group NOAA 1991-2020 normals from Altona'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 Altona, not an official NOAA class or a year-ahead forecast.
Questions about Altona's climate
How much rain does Altona get? ▼
How cold does Altona get in winter? ▼
How much energy does heating and cooling require in Altona? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Altona's primary station: ALTONA (USC00110140). 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 1701140). Match rule for Altona: 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 Altona 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.