Mundelein, 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 Mundelein's primary NOAA station, MUNDELEIN 4 WSW.
The climate verdict for Mundelein
Mundelein, Illinois has a mixed annual climate rather than one dominant extreme. Its NOAA normal shows an annual average of 48°F. Its climate comfort score of 59/100 (moderate) lands mid-pack nationally, exceeding 37% of station-mapped location scores.
- 48°F
- annual average temperature (NOAA normal)
- 59/100
- comfort score, above 37% of station-mapped location scores
- 38.5"
- annual precipitation · 43" snow
- 174 days
- frost-free days per growing season
Mundelein: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00115961 · Mundelein, IL 48°F mean · 38.5" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-MID · SWING-WIDE · COMF-MID · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 48°F
- RANK-COOL #2,127
- PHOTO-FINISH ≈ Rochelle
- PRCP-MID 38.5"
- SWING-WIDE 51°F
- COMF-MID 59/100
- LOAD-HEAT 6,875 HDD
- STN-1 USC00115961
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Rochelle, IL (+ 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.
- Mundelein (this station) 48°F
- Hot Mosby, MT 48°F
- Near Rochelle, IL 48°F
- Near Whitehall, NY 48°F
- Near Broken Bow, NE 48°F
Climate Living Index · Mundelein
Mundelein: 47/100 · grade D
Mundelein publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Mundelein, not an official NOAA rating. Rankings still use Comfort Score 59/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Precipitation balance | 38.5 in · 3.5 from 35 in | 87/100 · A |
| Normal heat + freeze calendar | 146 calendar days | 49/100 · D |
| Frost-free season | 174 days/year | 45/100 · D |
| Annual temperature balance | 47.9°F · 19.6° from 67.5°F | 31/100 · F |
| Snowfall burden | 43.1 inches/year | 25/100 · F |
Mundelein · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Mundelein is a continental Köppen climate: Dfa
Coldest-month mean 21.2°F and warmest-month mean 72.2°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
- 72.2°F
- Coldest month
- 21.2°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 Mundelein sits across the climate record
Three NOAA fields for Mundelein's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- 31st percentile warmth
- Mid-pack annual mean versus 6,861 station normals.
- Annual precipitation
- 55th percentile wetness
- Neither arid nor torrential versus 6,352 station totals.
- Seasonal temperature swing
- Wider than 84%
- Warmest-to-coldest month gap for Mundelein is large versus 6,861 complete station-years.
How Mundelein compares across U.S. station-mapped locations
Mundelein's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
59 37th percentile score exceeds 37% 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%). This entry sits in this band.
- 60–70: 1,236 station-mapped locations (20%). Above this entry.
- 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 | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 29°F (-2°C) | 14°F (-10°C) | 21°F (-6°C) | 1.8" | 11.0" | 29.0 | 0.0 |
| February | 33°F (0°C) | 16°F (-9°C) | 25°F (-4°C) | 1.9" | 12.8" | 26.6 | 0.0 |
| March | 44°F (7°C) | 26°F (-3°C) | 35°F (2°C) | 2.5" | 5.3" | 23.1 | 0.0 |
| April | 57°F (14°C) | 36°F (2°C) | 46°F (8°C) | 4.0" | 1.8" | 10.0 | 0.0 |
| May | 68°F (20°C) | 47°F (9°C) | 58°F (14°C) | 4.6" | 0.0" | 0.7 | 0.3 |
| June | 78°F (26°C) | 58°F (14°C) | 68°F (20°C) | 4.4" | 0.0" | 0.0 | 2.1 |
| July | 82°F (28°C) | 62°F (17°C) | 72°F (22°C) | 4.0" | 0.0" | 0.0 | 4.5 |
| August | 81°F (27°C) | 61°F (16°C) | 71°F (22°C) | 4.2" | 0.0" | 0.0 | 2.7 |
| September | 74°F (23°C) | 53°F (12°C) | 63°F (17°C) | 3.4" | 0.0" | 0.0 | 1.0 |
| October | 61°F (16°C) | 42°F (5°C) | 51°F (11°C) | 3.2" | 0.0" | 4.9 | 0.0 |
| November | 47°F (8°C) | 30°F (-1°C) | 38°F (3°C) | 2.5" | 2.5" | 17.8 | 0.0 |
| December | 34°F (1°C) | 20°F (-7°C) | 27°F (-3°C) | 2.1" | 9.7" | 27.5 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 82°F around July 10, short of 90°F on every date, while 146 dates carry a normal low at or below freezing, the coldest 13°F near January 21.
The freezing stretch
The normal low stays at or below 32°F into April 4, then returns to freezing around November 11, covering 146 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.
Where the wet dates fall
The likeliest wet date is May 11, when 44% of years recorded at least a hundredth of an inch. The driest is September 3 at 31%. Summed across the calendar, that is about 128 wet dates a year.
The widest day
September 17 carries the biggest normal gap between afternoon and dawn, 21°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Mundelein.
Where Mundelein Stands Nationally
Among the steadiest day-night climates ranked: even the widest normal daily swing holds to roughly 21°F.
Mundelein 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 and snowfall
Snow: 11.0"
10.2 days with precipitation
Snow: 12.8"
9.9 days with precipitation
Snow: 5.3"
10.5 days with precipitation
Snow: 1.8"
12.1 days with precipitation
13.5 days with precipitation
12.1 days with precipitation
9.5 days with precipitation
9.8 days with precipitation
9.0 days with precipitation
10.9 days with precipitation
Snow: 2.5"
9.6 days with precipitation
Snow: 9.7"
10.6 days with precipitation
Mundelein spreads its precipitation across the year
Neither half of the year dominates here: June through August take 33% of the annual total and December through February 15%, with neither reaching the 35% that would mark a distinct wet season. Mundelein has no dry season to plan around, though it does carry a wide 51°F gap between its warmest and coldest month.
The gap between the wettest and driest month still matters: May averages 4.6" and January 1.8". The three wettest months together take 34% 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.
How Mundelein's precipitation splits across the calendar
About 128 days a year record measurable precipitation here, carrying 38.4" between them, or roughly 0.30 inches on a typical wet day. That sits in the middle band: neither the many-light-days pattern of the Pacific Northwest and the Great Lakes, nor the few-heavy-events pattern of the Gulf and the desert Southwest.
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year and say nothing about the heaviest single storm on record.
Winter brings real snow to Mundelein
Mundelein averages 43.1 inches of snowfall a year, with February the snowiest month on the normals, spread across roughly 31 days that record measurable snow. That is depth accumulating on the ground, which is why it can exceed the annual precipitation figure: precipitation counts the liquid the snow melts down to, and fresh snow is mostly air.
- Annual snowfall: 43.1 inches of depth.
- Days recording measurable snow: about 31 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 11% of the year's precipitation.
NOAA 1991-2020 normals. The ten-to-one ratio is a convention, not a measurement: real ratios vary with temperature, so treat the share as an order of magnitude rather than an exact split.
Frost Dates & Growing Season
First Fall Freeze
October 20
50% probability date
Last Spring Freeze
April 29
50% probability date
Growing Season
174 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
6,875
Higher = more heating needed
Cooling Degree Days
693
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside IL closest to Mundelein 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 (48°F here).
- Arnold, NE 48°F · 0.0°F off
- Avon, NY 48°F · 0.0°F off
- Belle Fourche, SD 48°F · 0.0°F off
- Cascade, IA 48°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (38.5" here), excluding temperature-peer places.
- Franklin, WV 38.5" · 0.0" off
- Denton, TX 38.4" · 0.0" off
- Iowa City, IA 38.5" · 0.0" off
- Bedford, IA 38.4" · 0.0" off
Snow and freeze rhythm
When cold and snow define Mundelein
heating led · moderate · mid swing
Mundelein's energy balance leans toward cold weather: 6,875 annual heating degree days against 693 for cooling. Its 51.0°F seasonal range still makes the monthly rows more useful than the annual average alone.
Mundelein's frost-free season lasts about 174 days, a middle-length window whose endpoints matter more than the annual average. It describes freeze probability, not year-specific planting conditions.
-
1. Mundelein coldest normal
January
Averaging 21°F (-6°C), this month sits below freezing for the month as a whole, not merely overnight.
-
2. Mundelein typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Mundelein snow peak
February
Mundelein averages 43.1 inches of snow a year, with February the snowiest month on the normals.
Questions about Mundelein's climate
How much snow does Mundelein get? ▼
How cold does Mundelein get in winter? ▼
How much energy does heating and cooling require in Mundelein? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Mundelein's primary station: MUNDELEIN 4 WSW (USC00115961). 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 1751349). Match rule for Mundelein: 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 Mundelein 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.