Heilbronn weather in May

In May, Heilbronn sees average daytime highs of 19°C and overnight lows near 9°C, with 79 mm of rain across 13.1 wet days and about 15 hours of daylight. It is the 5th-warmest and 2nd-wettest month of the year here.

Highs climb over the month, from about 17°C in the first days to 20°C by the end. The sky is clear or mostly clear about 21% of the time in May, and the air most often feels dry.

Daylight stretches from about 14 h 18 min at the start of May to 15 h 42 min by month's end. Set against the rest of the year, May is Heilbronn's 6th-clearest and 8th-windiest month. For the whole year in context, see Heilbronn's year-round climate.

Daytime high
19°
5th warmest
Overnight low
8th coldest
Rainfall
79 mm
13.1 wet days
Daylight
15 h 06 min
4:47 AM – 7:52 PM
Cloud cover
65%
6th clearest
Wind
10 km/h
8th windiest
Solar energy
5.23 kWh/m²
Travel score
5.5
out of 10
Air quality
Moderate
PM2.5 11.6 µg/m³ · 2019

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 17°C in the first days to 20°C by the end.

A typical May day in Heilbronn reaches about 19°C in the afternoon and slips back to 9°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 12°C and 25°C. Set against its neighbours, May runs about 4°C warmer than April and about 3°C cooler than June.

10°20°30°151015202531
Avg high (°C)Avg low (°C)
1178
2178
3178
4178
5178
6188
7188
8188
9189
10189
11189
12189
13189
14189
15189
16199
17199
18199
191910
201910
211910
221910
232010
242010
252010
262010
272011
282011
292011
302011
312111

How May really feels in Heilbronn

Once humidity and wind are folded in, May averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

May sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Heilbronn weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -1°7612.34.48.50.0
Feb / -1°6611.34.39.80.2
Mar10° / 7612.5211.62.0
Apr15° / 5210.40.213.44.2
May19° / 7913.10155.5
Jun22° / 13°6612.2015.96.2
Jul24° / 14°7412.7015.66.5
Aug24° / 14°6211.1014.26.7
Sep19° / 11°6310.3012.46.0
Oct14° / 7211.80.110.53.7
Nov / 7211.61.48.91.1
Dec / 9014.64.78.10.0

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 21% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 16% of May, with mostly cloudy or overcast conditions the remaining 63%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13763
23763
33763
43763
53763
63763
73763
83763
93763
103664
113664
123664
133664
143664
153664
163763
173664
183664
193664
203664
213664
223664
233862
243763
253763
263763
273763
283862
293862
303862
313862

Chance of precipitation in May

Any precipitation

Heilbronn gets around 79 mm of rain over 13.1 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 42% and peaks near 44% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
143
243
344
444
544
644
744
844
944
1044
1144
1244
1344
1444
1544
1643
1743
1843
1942
2042
2141
2241
2341
2440
2540
2640
2740
2840
2940
3041
3141

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

Most of May feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, May lands in the dry band about 92% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)
19910
29910
39820
49820
59820
69820
79820
89730
99730
109730
119730
129730
139640
149640
159640
169550
179550
189460
199370
209370
219181
229091
2389101
2488111
2586122
2684142
2783152
2881163
2980173
3078193
3176204

Wind in May

Winds average 10 km/h in May.

Across May, daily wind ranges from about 9 km/h on the calmest days to 10 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
110calm
210calm
310calm
410calm
510calm
610calm
710calm
810calm
910calm
1010calm
1110calm
1210calm
1310calm
1410calm
1510calm
1610calm
1710calm
1810calm
1910calm
2010calm
2110calm
2210calm
2310calm
2410calm
259calm
269calm
279calm
289calm
299calm
309calm
319calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 14 h 18 min at the start of May to 15 h 42 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 84 minutes over May. Sunrise moves from 5:11 AM to 4:31 AM, and sunset from 7:30 PM to 8:10 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.35:117:30
214.45:097:31
314.45:077:33
414.55:067:34
514.55:047:36
614.65:027:37
714.65:017:39
814.74:597:40
914.74:577:42
1014.84:567:43
1114.84:547:45
1214.94:537:46
1314.94:517:47
1415.04:507:49
1515.04:487:50
1615.14:477:52
1715.14:467:53
1815.24:447:54
1915.24:437:56
2015.34:427:57
2115.34:417:58
2215.34:408:00
2315.44:388:01
2415.44:378:02
2515.44:368:03
2615.54:358:04
2715.54:348:06
2815.64:338:07
2915.64:338:08
3015.64:328:09
3115.74:318:10

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.23 kWh/m².

For context, solar energy here swings from a low near 0.75 kWh/m² to a high of 5.6 kWh/m² in June across the year — May's 5.23 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
14.9Bright
25.0Bright
35.0Bright
45.0Bright
55.0Bright
65.0Bright
75.0Bright
85.0Bright
95.1Bright
105.1Bright
115.1Bright
125.2Bright
135.2Bright
145.2Bright
155.2Bright
165.2Bright
175.3Bright
185.3Bright
195.3Bright
205.3Bright
215.3Bright
225.4Bright
235.4Bright
245.4Bright
255.4Bright
265.4Bright
275.4Bright
285.5Bright
295.5Bright
305.5Bright
315.5Bright
Planning a trip in May

Is May a good time to visit Heilbronn?

Our two travel scores rate May for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

5.5
Sightseeing
5th-best month of the year
2.2
Beach & pool
5th-best month of the year

May is a reasonable time to visit Heilbronn for sightseeing.

What to pack for Heilbronn in May

From May's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In May, Heilbronn sees daytime highs around 19°C and nights near 9°C. Worth packing: rain gear and sun protection. About 13 days see rain.

rain gearsun protection

UV index in Heilbronn in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Heilbronn peaks around July 15 at about 7 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near January 1 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 7 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJul 15UV 7Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar4Moderate
Apr4Moderate
May6High
Jun7High
Jul8Very high
Aug6High
Sep4Moderate
Oct3Moderate
Nov1Low
Dec1Low

Air quality in Heilbronn in May

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where May falls, not just the annual average.

Air quality in Heilbronn is worst in April — around 15 µg/m³ PM2.5 (moderate), about 1.8× the cleanest month (November, 8 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Heilbronn's WHO annual average of 11.6 µg/m³.

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodApr 1715 µg/m³Nov 238 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb10Good
Mar13Moderate
Apr15Moderate
May14Moderate
Jun15Moderate
Jul12Moderate
Aug13Moderate
Sep12Good
Oct10Good
Nov8Good
Dec8Good
Location & terrain

Where is Heilbronn?

Heilbronn sits at 49.1°N, 9.2°E, 173 m above sea level, in Germany. The nearest listed city is Neckarsulm, 5.0 km away.

Topography around Heilbronn

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Heilbronn.

Within 3 km, the terrain around Heilbronn has only modest variations in elevation — a maximum elevation change of 181 m around an average of 196 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 416 m; within 80 km, large variations in elevation — a maximum elevation change of 910 m.

The land around Heilbronn is covered by artificial surfaces (43%) and trees (34%) within 3 km, cropland (37%) and trees (31%) within 16 km, and trees (47%) and cropland (28%) within 80 km.

3 km
181 m
16 km
416 m
80 km
910 m
treesgrasslandcroplandartificial surfaceswater
May weather nearby: Neckarsulm 5.0 km · Brackenheim 13 km · Bad Rappenau 14 km · Öhringen 22 km · Eppingen 22 km · Marbach am Neckar 22 km · Sachsenheim 23 km · Bietigheim-Bissingen 23 km

Germany travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / F
230 V · 50 Hz
Prices
≈ 80% of US
price level, 2025
GDP per capita
$60,496
2025
Happiness
6.9 / 10
World Happiness, 2025
Safe drinking water
100%
of population, 2024
Homicide rate
0.9
per 100k, 2023
Road deaths
3.8
per 100k/yr, 2019
Income group
High
World Bank
English
Very high
EF EPI 615
Religion
none 44%Roman Catholic 25%Protestant 23%other 5%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Heilbronn (49.1399°, 9.2205°, elevation 173 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).