Alton, IL vs Denver, CO

Side-by-side comparison of monthly climate normals (NOAA 1991-2020).

Alton is warmer than Denver (55.7°F vs 51.4°F annual avg) and wetter than it (41.9 in vs 15.4 in per year). Alton has a Hot-summer humid continental climate; Denver a Semi-arid (cold) climate.

Alton, IL

Annual avg
55.7°F
Annual precip
41.9 in
Warmest month
July (87.3°F)
Coldest month
January (21.7°F)
Annual swing
48°F
Pleasant months
1 / 12
Hot-summer humid continental Dfa USDA Zone 7b

Denver, CO

Annual avg
51.4°F
Annual precip
15.4 in
Warmest month
July (90.2°F)
Coldest month
January (17.6°F)
Annual swing
43°F
Semi-arid (cold) BSk USDA Zone 7a

Best months to visit each city

Alton

J
F
M
A
M
J
J
A
S
O
N
D

Denver

J
F
M
A
M
J
J
A
S
O
N
D

Month-by-month comparison

Month Alton Denver
High Low Precip High Low Precip
January 39.0°F 21.7°F 2.53 in 46.5°F 17.6°F 0.46 in
February 43.7°F 25.2°F 2.52 in 47.5°F 19.3°F 0.53 in
March 53.5°F 34.7°F 3.46 in 56.4°F 27.1°F 1.12 in
April 66.1°F 45.2°F 4.92 in 62.5°F 33.7°F 1.67 in
May 75.0°F 56.1°F 5.46 in 71.7°F 43.4°F 2.29 in
June 83.7°F 65.6°F 3.40 in 84.1°F 52.9°F 1.68 in
July 87.3°F 69.3°F 3.95 in 90.2°F 59.3°F 2.12 in
August 86.0°F 67.3°F 3.30 in 87.9°F 57.2°F 1.83 in
September 80.1°F 59.8°F 3.38 in 80.1°F 48.2°F 1.51 in
October 67.9°F 48.0°F 2.93 in 66.7°F 35.7°F 0.98 in
November 54.3°F 36.5°F 3.43 in 54.8°F 25.5°F 0.70 in
December 43.5°F 27.1°F 2.59 in 45.9°F 17.7°F 0.47 in
Alton overview
Full climate profile
 Denver overview
Full climate profile