Mundelein has chilly, snowy winters and pleasant summers. A typical July afternoon reaches 83°, a January night drops to 15°, and about 43 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normalsUpdated once a decade
☀️
July high
83°
74th coolest of 2,886 Illinois towns
❄️
January low
15°
699th coldest of 2,886 Illinois towns
💧
Rain + melted snow
37 in
180th driest of 2,886 Illinois towns
🌨️
Snow a winter
43 in
40th snowiest of 2,880 Illinois towns
A normal year
What a year in Mundelein feels like
❄️
Winter
33° / 18°
Typical high / low · 13 days with an inch or more of snow
🌷
Spring
57° / 37°
Typical high / low · Last frost around Apr 29
☀️
Summer
81° / 60°
Typical high / low · 11 days reach 90° in a normal year
🍂
Fall
61° / 42°
Typical high / low · First frost around Oct 20
0°
10°
20°
40°
50°
60°
70°
80°
90°
100°
32°
30°
15°
34°
19°
45°
27°
57°
37°
69°
47°
79°
57°
83°
63°
81°
61°
74°
54°
61°
42°
47°
31°
35°
21°
JanJFebFMarMAprAMayMJunJJulJAugASepSOctONovNDecD
32°, freezingBar runs from the typical overnight low up to the afternoon high
Best months to be outsideMayJunJulAugSepHighs of 62–84° and lows of 40° or more
Month by month
Mundelein weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
Month
High
Low
Rain + melt
Snow
Wet days
Snow on ground
30-yr range
January
30°
15°
1.9"
11.0"
10
18
13° – 34°
February
34°
19°
1.8"
12.8"
10
16
14° – 37°
March
45°
27°
2.3"
5.3"
11
6
28° – 51°
April
57°
37°
3.9"
1.8"
12
1
39° – 53°
May
69°
47°
4.3"
0
14
0
52° – 65°
June
79°
57°
4.5"
0
12
0
64° – 73°
July
83°
63°
3.8"
0
10
0
67° – 79°
August
81°
61°
3.8"
0
10
0
65° – 77°
September
74°
54°
3.5"
0
9
0
58° – 69°
October
61°
42°
3.2"
0
11
0
47° – 58°
November
47°
31°
2.5"
2.5"
10
2
31° – 48°
December
35°
21°
2.0"
9.7"
11
12
16° – 38°
Year
58°
40°
37.3"
43.1"
128
55
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain & snow
Rain and snow in Mundelein
Mundelein gets 37 inches of rain and melted snow a year. June is the wettest month and February the driest. Rain or snow falls on about 128 days a year. Snow covers the ground about 55 days of the year.
💧
37 in
Rain + melted snow a year
Less rain than 59% of U.S. towns
❄️
43 in
Snow in a normal winter
More snow than 74% of U.S. towns
⛄
55 days
With 1"+ of snow on the ground
More than 69% of U.S. towns
Rain + melted snow by month
Inches of water
4.5"
JFMAMJJASOND
Snowfall by month
Inches of snow
13"
JFMAMJJASOND
Frost & the growing season
About 172 frost-free days a year
In half of years the last 32° night comes by April 29 and the first one by October 20. That leaves about 172 frost-free days for gardens, shorter than 58% of U.S. towns.
🌱 Apr 29
🍂 Oct 20
172 frost-free days
JFMAMJJASOND
🥶
140
nights at or below 32° in a normal year
🧊
12
nights below 0° in a normal year
🔥
11
days that reach 90° in a normal year
Freezing nights by month
Average nights at or below 32°
JFMAMJJASOND
90° days by month
Average days at 90° or more
JFMAMJJASOND
Heating & cooling
Heating and cooling a home in Mundelein
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Mundelein, 91% of that work is heating and 9% is cooling, so the furnace matters far more than the air conditioner.
🔥
6,875 heating degree daysMore heating than 71% of U.S. towns
❄️
693 cooling degree daysLess cooling than 61% of U.S. towns
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Around Mundelein
Mundelein and its neighbors
Mundelein borders 8 towns with climate data. January nights across them vary by 1.1°. Hawthorn Woods has the coldest January nights (15°) and Long Grove the hottest July afternoons (83°). Mundelein’s January low is 15° and its July high 83°.
Compared with every U.S. town and city on TownTapestry, each counted once.
Then and now
Warmer than it used to be
+1.2°1991–2020 average vs. the 20th century (1901–2000)
The last 30 years in Mundelein averaged 1.2° warmer than the 1900s. The biggest change is in December (+2.6°). The shift is smaller than in 52% of U.S. towns.
❄️ Winter+2.3°now 26°, was 23°
🌷 Spring+1.1°now 47°, was 46°
☀️ Summer+0.6°now 71°, was 70°
🍂 Fall+0.9°now 52°, was 51°
Change by month1991–2020 average minus 1901–2000 average, at Mundelein’s spot on NOAA’s grid
+0.1°
+2.6°
JanJFebFMarMAprAMayMJunJJulJAugASepSOctONovNDecD
Year to year
How much a month can swing
A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 14° to 37°. June is the most reliable, staying within 9°.
0°
10°
20°
30°
40°
50°
60°
70°
80°
90°
JanJFebFMarMAprAMayMJunJJulJAugASepSOctONovNDecD
Coldest to warmest month in 30 yearsNormal
Questions
Common questions about Mundelein’s climate
What is the coldest month in Mundelein?
January, with a typical high of 30° and a low of 15°.
What is the hottest month in Mundelein?
July, with a typical high of 83° and a low of 63°. About 11 days a year reach 90°.
How much snow does Mundelein get?
About 43 inches in a normal winter, most of it in February.
When is the first frost in Mundelein?
In half of years the first 32° night comes by October 20, and the last spring frost by April 29.
What is the rainiest month in Mundelein?
June, with 4.5 inches of rain and melted snow. The year totals 37 inches.
📍Temperatures and rainfall come from NOAA’s gridded climate normals for Mundelein itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Mundelein 4 Wsw, IL (3 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.