Johnston city, Iowa

Official LSAD Designation: Johnston city • Census GEOID: 1939765 • Polk County

Climate Normals & Weather Observations

30-year climate normals (1991–2020) and weather observations for Johnston city.

Reference Weather Station: DES MOINES WSFO-JOHNSTON, IA US (ID: USC00132209) • Located 3.1 miles from community center • Elevation: 292.3 m

Month	Average High (°F)	Average Low (°F)	Mean Temp (°F)	Precipitation (in)
January	30.0°	13.1°	21.5°	1.01"
February	35.1°	17.3°	26.2°	1.25"
March	48.6°	28.8°	38.7°	2.15"
April	61.5°	40.1°	50.8°	4.00"
May	71.8°	51.8°	61.8°	4.84"
June	80.9°	62.0°	71.5°	5.35"
July	84.7°	65.6°	75.2°	4.27"
August	82.9°	63.6°	73.2°	3.97"
September	76.2°	55.1°	65.6°	3.40"
October	63.1°	42.5°	52.8°	2.51"
November	47.7°	29.9°	38.8°	1.95"
December	35.2°	19.0°	27.1°	1.46"

2010–2025, completed calendar years only.

NOAA station DES MOINES WSFO-JOHNSTON, IA US (ID: USC00132209) • 3.1 miles from community center .

This is the same reference station used for monthly normals.

Show annual mean of daily highs and lows

Annual mean Annual mean of daily highs Annual mean of daily lows

Annual temperature data table (°F)

Annual station temperatures, 2010–2025. Unavailable means no reported value.
Year	Annual mean (°F)	Annual mean of daily highs (°F)	Annual mean of daily lows (°F)
2010	49.4	58.9	39.8
2011	50.2	59.7	40.7
2012	Unavailable	Unavailable	Unavailable
2013	48.8	58.5	39.1
2014	46.6	56.2	37.1
2015	50.4	59.6	41.1
2016	53.0	62.2	43.7
2017	52.4	62.2	42.6
2018	49.8	59.1	40.6
2019	49.0	58.1	39.8
2020	Unavailable	Unavailable	Unavailable
2021	52.2	62.0	42.4
2022	49.9	60.5	39.3
2023	52.4	62.5	42.4
2024	53.5	63.5	43.5
2025	51.8	61.8	41.7

Source: NOAA NCEI 1991–2020 U.S. Climate Normals, National Weather Service.