Chicago Northerly Island, IL Climate: Temperature by Month
Explore NOAA NCEI's 1991–2020 climate normals → and a clearly labeled PlainClimate comfort calculation
30-year climate normals (1991-2020) from Chicago Northerly Island's primary NOAA station, CHICAGO NORTHERLY IS.
The climate verdict for Chicago Northerly Island
Chicago Northerly Island, Illinois has a mixed annual climate rather than one dominant extreme. Its NOAA normal shows an annual average of 51°F. July is the warmest month at 74°F and January the coldest at 26°F.
- 51°F
- average temperature, NOAA 1991-2020 normal
- 209 days
- growing season, frost-free days
Chicago Northerly Island: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00111550 · Chicago Northerly Island, IL 51°F mean
TEMP-COOL · RANK-MID · PHOTO-FINISH · PRCP-UNK · SWING-WIDE · COMF-UNK · LOAD-HEAT · STN-1 · BOOK-PART
- TEMP-COOL 51°F
- RANK-MID #3,019
- PHOTO-FINISH ≈ Hoytville
- PRCP-UNK Rain n/a
- SWING-WIDE 48°F
- COMF-UNK Comfort n/a
- LOAD-HEAT 6,018 HDD
- STN-1 USC00111550
- BOOK-PART 4/6 fields
Nearest mean-temperature peer: Hoytville, OH (+ 0 °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.
- Chicago Norther… (this station) 51°F
- Cold Fremont, OH 51°F
- Hot Tiffin, OH 51°F
- Near Hoytville, OH 51°F
- Near Kenton, OH 51°F
Climate Living Index · Chicago Northerly Island
Chicago Northerly Island: 58/100 · grade C
Chicago Northerly Island publishes 3 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 3 missing weights rescale to 100.
PlainClimate-derived for Chicago Northerly Island, not an official NOAA rating. Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Frost-free season | 209 days/year | 71/100 · B |
| Normal heat + freeze calendar | 115 calendar days | 67/100 · C |
| Annual temperature balance | 50.8°F · 16.7° from 67.5°F | 44/100 · D |
Chicago Northerly Island · 2026-08-04 · NOAA NCEI Climate Normals · method .
National standing · heating-led station
Where Chicago Northerly Island sits across the climate record
Available NOAA 1991–2020 fields for Chicago Northerly Island are ranked only against stations that publish the same field, missing metrics stay blank rather than estimated.
- Annual temperature
- 44th percentile warmth
- Mid-pack annual mean versus 6,861 station normals.
- Seasonal temperature swing
- Wider than 73%
- Warmest-to-coldest month gap for Chicago Northerly Island is large versus 6,861 complete station-years.
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|
| January | 32°F (0°C) | 20°F (-7°C) | 26°F (-3°C) | N/A | 25.9 | 0.0 |
| February | 36°F (2°C) | 23°F (-5°C) | 29°F (-1°C) | N/A | 23.4 | 0.0 |
| March | 45°F (7°C) | 31°F (-1°C) | 38°F (3°C) | N/A | 14.2 | 0.0 |
| April | 55°F (13°C) | 40°F (5°C) | 48°F (9°C) | N/A | 2.7 | 0.0 |
| May | 66°F (19°C) | 50°F (10°C) | 58°F (14°C) | N/A | 0.0 | 0.5 |
| June | 76°F (24°C) | 60°F (16°C) | 68°F (20°C) | N/A | 0.0 | 2.4 |
| July | 81°F (27°C) | 67°F (20°C) | 74°F (23°C) | N/A | 0.0 | 5.1 |
| August | 80°F (27°C) | 67°F (20°C) | 74°F (23°C) | N/A | 0.0 | 3.6 |
| September | 73°F (23°C) | 60°F (16°C) | 67°F (19°C) | N/A | 0.0 | 1.8 |
| October | 61°F (16°C) | 48°F (9°C) | 54°F (12°C) | N/A | 0.3 | 0.0 |
| November | 49°F (9°C) | 36°F (2°C) | 43°F (6°C) | N/A | 8.4 | 0.0 |
| December | 37°F (3°C) | 25°F (-4°C) | 31°F (-1°C) | N/A | 21.7 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 81°F around July 20, short of 90°F on every date, while 115 dates carry a normal low at or below freezing, the coldest 20°F near January 16.
The freezing stretch
The normal low stays at or below 32°F into March 20, then returns to freezing around November 27, covering 115 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
May 29 carries the biggest normal gap between afternoon and dawn, 16°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Chicago Northerly Island.
Where Chicago Northerly Island Stands Nationally
Among the steadiest day-night climates ranked: even the widest normal daily swing holds to roughly 16°F.
Chicago Northerly Island earns one nationally notable standing (outer quintile) against 6,860 NOAA 1991–2020 normals stations, middle-of-the-pack metrics stay silent here.
Monthly Precipitation
Average monthly rainfall
Frost Dates & Growing Season
First Fall Freeze
November 5
50% probability date
Last Spring Freeze
April 10
50% probability date
Growing Season
209 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
6,018
Higher = more heating needed
Cooling Degree Days
862
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside IL closest to Chicago Northerly Island 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 (51°F here).
- Ashland, NE 51°F · 0.0°F off
- Attica, IN 51°F · 0.0°F off
- Brady, NE 51°F · 0.0°F off
- Bridgehampton, NY 51°F · 0.0°F off
Data-derived climate profile
How Chicago Northerly Island's climate pattern fits together
heating led · mid swing
Chicago Northerly Island's energy balance leans toward cold weather: 6,018 annual heating degree days against 862 for cooling. Its 48.1°F seasonal range still makes the monthly rows more useful than the annual average alone.
Chicago Northerly Island's frost-free season lasts about 209 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 Chicago Northerly Island's middle-range seasonal profile. The measured spread is 48.1°F. The annual average is 51°F. Neither the annual mean nor one extreme month represents the full calendar on its own.
A moisture-range label is withheld because Chicago Northerly Island's annual precipitation total is unavailable. Monthly source values remain visible where NOAA provides them, and no annual amount is reconstructed from incomplete data.
These labels group NOAA 1991-2020 normals from Chicago Northerly Island'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 Chicago Northerly Island, not an official NOAA class or a year-ahead forecast.
Questions about Chicago Northerly Island's climate
How cold does Chicago Northerly Island get in winter? ▼
How much energy does heating and cooling require in Chicago Northerly Island? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Chicago Northerly Island's primary station: CHICAGO NORTHERLY IS (USC00111550). For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The conservative exact name-and-state crosswalk finds no Census place match, so PlainClimate treats this as a station-mapped location and does not claim it is a municipality. No exact Gazetteer row for Chicago Northerly Island; facility counts that depend on place identity are therefore an upper bound, not a municipal census.
On this page every temperature, precipitation, and derived score for Chicago Northerly Island 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.