Helena, MT vs Phoenix, AZ

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

Helena is cooler than Phoenix (45.5°F vs 72.5°F annual avg) and similar rainfall to it (11.4 in vs 8.9 in per year). Helena has a Semi-arid (cold) climate; Phoenix a Desert (hot) climate.

Helena, MT

Annual avg
45.5°F
Annual precip
11.4 in
Warmest month
July (86.1°F)
Coldest month
January (13.5°F)
Annual swing
47.6°F
Semi-arid (cold) BSk USDA Zone 6b

Phoenix, AZ

Annual avg
72.5°F
Annual precip
8.9 in
Warmest month
July (104.0°F)
Coldest month
December (42.7°F)
Annual swing
39.1°F
Pleasant months
2 / 12
Desert (hot) BWh USDA Zone 9b

Best months to visit each city

Helena

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

Phoenix

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

Month-by-month comparison

Month Helena Phoenix
High Low Precip High Low Precip
January 32.4°F 13.5°F 0.39 in 65.4°F 44.1°F 1.17 in
February 37.2°F 17.2°F 0.42 in 68.1°F 46.1°F 1.21 in
March 47.5°F 24.6°F 0.52 in 75.0°F 50.9°F 1.09 in
April 56.7°F 32.4°F 1.02 in 82.5°F 56.6°F 0.35 in
May 66.4°F 41.5°F 1.95 in 91.5°F 64.7°F 0.19 in
June 74.7°F 48.7°F 2.21 in 101.5°F 72.7°F 0.03 in
July 86.1°F 55.1°F 1.06 in 104.0°F 80.8°F 0.81 in
August 84.6°F 52.9°F 1.04 in 102.5°F 80.5°F 0.96 in
September 73.3°F 44.6°F 0.96 in 97.5°F 74.7°F 0.71 in
October 57.6°F 33.5°F 0.78 in 86.3°F 62.7°F 0.67 in
November 42.8°F 22.8°F 0.59 in 74.0°F 50.8°F 0.90 in
December 32.6°F 14.2°F 0.46 in 63.9°F 42.7°F 0.81 in
Helena overview
Full climate profile
 Phoenix overview
Full climate profile