Heiloo weather in August

In August, Heiloo sees average daytime highs of 20°C and overnight lows near 15°C, with 90 mm of rain across 13.3 wet days and about 14.5 hours of daylight. It is the 1st-warmest and 1st-wettest month of the year here.

Highs ease over the month, from about 21°C in the first days to 19°C by the end. The sky is clear or mostly clear about 22% of the time in August, and the air most often feels comfortable.

Daylight stretches from about 15 h 24 min at the start of August to 13 h 30 min by month's end. Set against the rest of the year, August is Heiloo's 3rd-clearest and 11th-windiest month. For the whole year in context, see Heiloo's year-round climate.

Daytime high
20°
1st warmest
Overnight low
15°
12th coldest
Rainfall
90 mm
13.3 wet days
Daylight
14 h 30 min
5:30 AM – 8:01 PM
Cloud cover
61%
3rd clearest
Wind
17 km/h
11th windiest
Solar energy
4.6 kWh/m²
Travel score
5.9
out of 10

Heiloo is town and municipality in the Netherlands.

Density
1,270/km²
people per km²

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

Temperature in August

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 21°C in the first days to 19°C by the end.

A typical August day in Heiloo reaches about 20°C in the afternoon and slips back to 15°C overnight — a 5°C spread between the day's warmth and the night's chill. On most days the high lands between 17°C and 24°C. Set against its neighbours, August runs on par with July and about 3°C warmer than September.

10°15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
12116
22116
32116
42116
52116
62116
72116
82116
92115
102115
112115
122115
132115
142015
152015
162015
172015
182015
192015
202015
212015
222015
232015
242015
252015
262015
271915
281914
291914
301914
311914

How August really feels in Heiloo

Once humidity and wind are folded in, August 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

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

Heiloo weather by month

How August compares with the rest of the year at a glance. August is the 1st-warmest and 1st-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 6913.20.980.3
Feb / 5410.91.49.50.4
Mar / 5210.80.711.51.5
Apr12° / 4410.1013.63.0
May15° / 10°5810.4015.54.6
Jun18° / 13°6311.3016.55.5
Jul20° / 15°7913.1016.15.9
Aug20° / 15°9013.3014.55.9
Sep18° / 13°8412.7012.45.2
Oct14° / 10°8814.1010.33.6
Nov10° / 7714.80.28.51.8
Dec / 8014.30.97.50.7

Cloud cover in August

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 22% of the time in August.

Beyond those clear spells, partly cloudy skies cover about 24% of August, with mostly cloudy or overcast conditions the remaining 54%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15149
25050
35050
44951
54951
64951
74852
84951
94852
104852
114852
124753
134753
144753
154753
164753
174654
184654
194555
204555
214555
224456
234456
244456
254357
264357
274357
284258
294357
304258
314258

Chance of precipitation in August

Any precipitation

Heiloo gets around 90 mm of rain over 13.3 wet days in August, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 43% and peaks near 46% on the wettest days.

0%20%40%60%151015202531
Rain chance (%)
141
241
340
440
540
640
740
840
940
1041
1141
1242
1342
1443
1543
1644
1744
1845
1945
2045
2146
2246
2346
2446
2546
2646
2745
2845
2945
3045
3144

Humidity in August

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, August lands in the comfortable band about 45% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)
11948304
21948304
31947304
42047304
52046304
62146304
72245304
82245304
92344294
102344294
112443294
122443294
132543284
142543284
152543274
162644274
172644264
182644254
192745244
202745234
212846224
222946214
233046204
243246194
253345183
263545173
273744163
283844153
294043152
304242142
314341142

Wind in August

Winds average 17 km/h in August.

Across August, daily wind ranges from about 16 km/h on the calmest days to 17 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202531
Wind speed (km/h)Feels
116light breeze
216light breeze
316light breeze
416light breeze
516light breeze
616light breeze
716light breeze
816light breeze
916light breeze
1016light breeze
1116light breeze
1216light breeze
1317light breeze
1417light breeze
1517light breeze
1617light breeze
1717light breeze
1817light breeze
1917light breeze
2017light breeze
2117light breeze
2217light breeze
2317light breeze
2417light breeze
2517light breeze
2617light breeze
2717light breeze
2817light breeze
2917light breeze
3017light breeze
3117light breeze

Sunrise & sunset in August

DaylightNight

Daylight runs from about 15 h 24 min at the start of August to 13 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 114 minutes over August. Sunrise moves from 5:05 AM to 5:56 AM, and sunset from 8:29 PM to 7:27 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
115.45:058:29
215.35:078:28
315.35:088:26
415.25:108:24
515.25:128:22
615.15:138:21
715.15:158:19
815.05:178:17
914.95:188:15
1014.95:208:13
1114.85:228:11
1214.85:238:09
1314.75:258:07
1414.65:278:05
1514.65:288:03
1614.55:308:01
1714.45:327:59
1814.45:337:56
1914.35:357:54
2014.35:377:52
2114.25:397:50
2214.15:407:48
2314.15:427:45
2414.05:447:43
2513.95:457:41
2613.95:477:38
2713.85:497:36
2813.75:517:34
2913.75:527:31
3013.65:547:29
3113.55:567:27

Solar energy in August

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in August, about 4.6 kWh/m².

For context, solar energy here swings from a low near 0.57 kWh/m² to a high of 5.65 kWh/m² in June across the year — August's 4.6 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.3Bright
25.2Bright
35.2Bright
45.2Bright
55.1Bright
65.1Bright
75.0Bright
85.0Bright
94.9Bright
104.9Bright
114.8Bright
124.8Bright
134.7Bright
144.7Bright
154.6Bright
164.6Bright
174.5Bright
184.5Bright
194.4Bright
204.4Bright
214.3Bright
224.3Bright
234.2Bright
244.2Bright
254.1Bright
264.1Bright
274.0Bright
284.0Moderate
293.9Moderate
303.9Moderate
313.8Moderate
Planning a trip in August

Is August a good time to visit Heiloo?

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

5.9
Sightseeing
1st-best month of the year
3.1
Beach & pool
1st-best month of the year

August is a reasonable time to visit Heiloo for sightseeing.

What to pack for Heiloo in August

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

In August, Heiloo sees daytime highs around 20°C and nights near 15°C. Worth packing: rain gear and sun protection. About 13 days see rain.

rain gearsun protection

Sea temperature near Heiloo in August

The nearest coast averages about 19°C in August — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in August at about 19°C and coldest in February near 5°C.

The water stays below 20°C all year — cool enough that most swimmers want a wetsuit.

5°10°15°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshing
Sea temperature (°C)Comfort
Jan6Bracing
Feb5Bracing
Mar6Bracing
Apr8Bracing
May12Bracing
Jun15Bracing
Jul17Cool
Aug19Cool
Sep17Cool
Oct15Bracing
Nov11Bracing
Dec8Bracing

UV index in Heiloo in August

LowModerateHighVery highExtreme

Clear-sky midday UV in August 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 Heiloo peaks around July 14 at about 6 (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 6 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighModerateLowJul 14UV 6Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb1Low
Mar3Moderate
Apr3Moderate
May5High
Jun6High
Jul6High
Aug6High
Sep4Moderate
Oct2Moderate
Nov1Low
Dec1Low
Location & terrain

Where is Heiloo?

Heiloo sits at 52.6°N, 4.7°E, 2 m above sea level, in The Netherlands. The nearest listed city is Alkmaar, 5.0 km away.

Topography around Heiloo

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

Within 3 km, the terrain around Heiloo has only modest variations in elevation — a maximum elevation change of 25 m around an average of 2 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 65 m; within 80 km, only modest variations in elevation — a maximum elevation change of 90 m.

The land around Heiloo is covered by grassland (50%) and trees (23%) within 3 km, grassland (36%) and water (33%) within 16 km, and water (47%) and grassland (24%) within 80 km.

3 km
25 m
16 km
65 m
80 km
90 m
treesgrasslandcroplandartificial surfaceswaterwetland
August weather nearby: Alkmaar 5.0 km · Castricum 6.0 km · Bergen 7.0 km · Heemskerk 10 km · Heerhugowaard 13 km · Beverwijk 13 km · Assendelft 15 km · Velsen-Zuid 16 km

The Netherlands travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / F
230 V · 50 Hz
Prices
≈ 84% of US
price level, 2025
GDP per capita
$73,684
2025
Happiness
7.2 / 10
World Happiness, 2025
Safe drinking water
100%
of population, 2024
Homicide rate
0.7
per 100k, 2023
Road deaths
4
per 100k/yr, 2019
Income group
High
World Bank
English
Very high
EF EPI 624
Religion
none 54%Roman Catholic 20%Protestant 15%other 6%

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 Heiloo (52.6025°, 4.6882°, elevation 2 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. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).