Iserlohn, North Rhine-Westphalia climate

Cfb Oceanic / temperate

Iserlohn has a seasonal cool-temperate climate (Oceanic / temperate, Köppen Cfb). The hottest month is July with an average daily high near 76°F, while the coldest is January averaging around 32°F at night. Around 27 inches of precipitation falls each year, peaking in August (3.2 inches) and easing off in April (1.4 inches). At latitude 52°N, day length swings from 7.6 hours in midwinter to 16.4 hours at midsummer.

☀️ Summers

Mild

Highs near 76°F in July.

About 5 days a year above 90 °F

❄️ Winters

Chilly

Lows near 32°F in January.

About 57 freezing nights a year

🌧️ Rain

Moderate rainfall

About 27 in of rain a year.

Wettest in August

⛅ Sky & trend

Often cloudy

Cloudy skies much of the year.

Temperature & precipitation

Daily high–low temperature range with the monthly average, plus monthly precipitation · 1991–2020 normals · hover a month for the exact figures

Clear vs cloudy days

Share of days each month that are clear, partly cloudy or cloudy · 1991–2020 · hover a month for the day counts

Iserlohn climate normals (1991–2020)

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Avg high (°F)	42	44	50	60	66	72	76	75	69	59	50	44
Avg temp (°F)	37	38	43	50	56	62	66	65	59	52	45	39
Avg low (°F)	32	33	35	40	45	52	55	56	50	45	39	35
Precipitation (in)	2.3	2.0	1.9	1.4	2.3	2.4	3.2	3.2	2.1	2.1	2.3	2.1

Jan – Jun	Jan	Feb	Mar	Apr	May	Jun
Avg high (°F)	42	44	50	60	66	72
Avg temp (°F)	37	38	43	50	56	62
Avg low (°F)	32	33	35	40	45	52
Precipitation (in)	2.3	2.0	1.9	1.4	2.3	2.4

Jul – Dec	Jul	Aug	Sep	Oct	Nov	Dec
Avg high (°F)	76	75	69	59	50	44
Avg temp (°F)	66	65	59	52	45	39
Avg low (°F)	55	56	50	45	39	35
Precipitation (in)	3.2	3.2	2.1	2.1	2.3	2.1

How often — frequency of weather events

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Days with measurable rain (days)	16	14	13	10	13	13	14	14	12	13	15	18
Days with high ≥ 90°F (days)	—	—	—	—	—	0.4	2	2	0.3	—	—	—
Days with low ≤ 32°F (days)	13	13	10	3	0.6	—	—	—	—	2	6	11

Jan – Jun	Jan	Feb	Mar	Apr	May	Jun
Days with measurable rain (days)	16	14	13	10	13	13
Days with high ≥ 90°F (days)	—	—	—	—	—	0.4
Days with low ≤ 32°F (days)	13	13	10	3	0.6	—

Jul – Dec	Jul	Aug	Sep	Oct	Nov	Dec
Days with measurable rain (days)	14	14	12	13	15	18
Days with high ≥ 90°F (days)	2	2	0.3	—	—	—
Days with low ≤ 32°F (days)	—	—	—	2	6	11

Sky & atmosphere

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Cloud cover (%)	74	73	71	68	70	72	69	68	67	70	75	74
Clear days (≤ 30% cloud)	3	3	4	4	4	3	4	4	4	3	2	3
Partly cloudy days (30–70%)	8	6	7	8	8	8	9	9	8	9	8	7
Cloudy days (≥ 70%)	20	19	20	17	19	19	18	18	17	19	20	22
Relative humidity (%)	94	92	87	81	79	77	72	71	77	85	92	94
Wind speed (mph)	8.7	8.3	7.6	6.1	5.9	5.7	5.7	5.7	6.0	6.9	7.2	8.1

Jan – Jun	Jan	Feb	Mar	Apr	May	Jun
Cloud cover (%)	74	73	71	68	70	72
Clear days (≤ 30% cloud)	3	3	4	4	4	3
Partly cloudy days (30–70%)	8	6	7	8	8	8
Cloudy days (≥ 70%)	20	19	20	17	19	19
Relative humidity (%)	94	92	87	81	79	77
Wind speed (mph)	8.7	8.3	7.6	6.1	5.9	5.7

Jul – Dec	Jul	Aug	Sep	Oct	Nov	Dec
Cloud cover (%)	69	68	67	70	75	74
Clear days (≤ 30% cloud)	4	4	4	3	2	3
Partly cloudy days (30–70%)	9	9	8	9	8	7
Cloudy days (≥ 70%)	18	18	17	19	20	22
Relative humidity (%)	72	71	77	85	92	94
Wind speed (mph)	5.7	5.7	6.0	6.9	7.2	8.1

Methodology & sources

Temperature & precipitation — 1991–2020 normals computed from 17 years of daily observations at Werl, a weather station, about 26 km from the city centre. The underlying daily records come from NOAA's global station network.

Cloud, humidity, wind & sunshine — modelled estimates from NASA POWER, NASA's satellite-and-reanalysis climatology. This is the standard global source for atmospheric variables, which are not measured at most weather stations.

How we build these numbers →