Kalutara weather in May

In May, Kalutara sees average daytime highs of 29°C and overnight lows near 26°C, with 334 mm of rain across 29.7 wet days and about 12.3 hours of daylight. It is the 3rd-warmest and 3rd-wettest month of the year here.

Day-to-day highs hold fairly steady near 29°C through the month. The sky is clear or mostly clear about 6% of the time in May, and the air most often feels miserable.

Daylight stretches from about 12 h 12 min at the start of May to 12 h 24 min by month's end. Set against the rest of the year, May is Kalutara's 8th-clearest and 5th-windiest month. For the whole year in context, see Kalutara's year-round climate.

Daytime high
29°
3rd warmest
Overnight low
26°
12th coldest
Rainfall
334 mm
29.7 wet days
Daylight
12 h 18 min
5:57 AM – 6:15 PM
Cloud cover
79%
8th clearest
Wind
13 km/h
5th windiest
Solar energy
4.69 kWh/m²
Travel score
3.0
out of 10

Kalutara is city in Western Province, Sri Lanka.

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

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 29°C through the month.

A typical May day in Kalutara reaches about 29°C in the afternoon and slips back to 26°C overnight — a 3°C spread between the day's warmth and the night's chill. On most days the high lands between 28°C and 30°C. Set against its neighbours, May runs on par with April and on par with June.

25°28°30°33°35°151015202531
Avg high (°C)Avg low (°C)
12926
22926
32926
42926
52926
62926
72926
82926
92926
102926
112926
122926
132926
142926
152926
162926
172926
182926
192926
202926
212926
222926
232926
242926
252926
262926
272926
282926
292926
302926
312926

How May really feels in Kalutara

Once humidity and wind are folded in, May averages 31 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
31
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

The story in May is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Kalutara weather by month

How May compares with the rest of the year at a glance. May is the 3rd-warmest and 3rd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 24°7911.111.75.5
Feb29° / 24°649.911.85.4
Mar30° / 25°7914.3124.7
Apr30° / 26°18724.712.13.4
May29° / 26°33429.712.33.0
Jun28° / 26°33128.812.43.1
Jul28° / 25°29428.912.33.4
Aug28° / 25°26728.812.23.5
Sep28° / 25°29227.7123.6
Oct28° / 25°35027.711.93.5
Nov28° / 25°3362411.73.8
Dec28° / 24°18419.111.64.5

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 6% 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 78%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
12971
22773
32773
42674
52674
62674
72575
82575
92575
102575
112575
122476
132476
142476
152476
162377
172377
182377
192278
202179
212080
221981
231981
241882
251783
261783
271684
281684
291486
301486
311387

Chance of precipitation in May

Any precipitation

Kalutara gets around 334 mm of rain over 29.7 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 96% and peaks near 97% on the wettest days.

0%20%40%60%80%100%151015202531
Rain chance (%)
193
293
394
494
594
694
794
895
995
1095
1195
1295
1396
1496
1596
1696
1796
1896
1997
2097
2197
2297
2397
2497
2597
2697
2797
2897
2997
3097
3197

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the miserable band about 97% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Oppressive (%)Miserable (%)
1496
2496
3496
4397
5397
6397
7397
8397
9397
10397
11397
12397
13397
14397
15397
16397
17298
18298
19298
20298
21298
22298
23298
24397
25397
26397
27397
28397
29496
30496
31496

Wind in May

Winds average 13 km/h in May.

Across May, daily wind ranges from about 10 km/h on the calmest days to 15 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202531
Wind speed (km/h)Feels
110calm
210calm
310calm
410calm
510calm
611calm
711calm
811calm
911calm
1012calm
1112calm
1212light breeze
1312light breeze
1413light breeze
1513light breeze
1613light breeze
1713light breeze
1813light breeze
1914light breeze
2014light breeze
2114light breeze
2214light breeze
2314light breeze
2414light breeze
2514light breeze
2615light breeze
2715light breeze
2815light breeze
2915light breeze
3015light breeze
3115light breeze

Sunrise & sunset in May

DaylightNight

Daylight runs from about 12 h 12 min at the start of May to 12 h 24 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 12 minutes over May. Sunrise moves from 6:01 AM to 5:57 AM, and sunset from 6:14 PM to 6:18 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.26:016:14
212.26:006:14
312.26:006:14
412.26:006:14
512.25:596:14
612.35:596:14
712.35:596:14
812.35:596:15
912.35:596:15
1012.35:586:15
1112.35:586:15
1212.35:586:15
1312.35:586:15
1412.35:586:15
1512.35:586:15
1612.35:576:15
1712.35:576:16
1812.35:576:16
1912.35:576:16
2012.35:576:16
2112.35:576:16
2212.35:576:16
2312.35:576:16
2412.35:576:17
2512.35:576:17
2612.35:576:17
2712.35:576:17
2812.35:576:17
2912.35:576:18
3012.35:576:18
3112.45:576:18

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 4.69 kWh/m².

For context, solar energy here swings from a low near 4.47 kWh/m² to a high of 6.09 kWh/m² in March across the year — May's 4.69 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.1Bright
25.1Bright
35.0Bright
45.0Bright
55.0Bright
65.0Bright
74.9Bright
84.9Bright
94.9Bright
104.8Bright
114.8Bright
124.8Bright
134.8Bright
144.7Bright
154.7Bright
164.7Bright
174.7Bright
184.7Bright
194.7Bright
204.6Bright
214.6Bright
224.6Bright
234.6Bright
244.6Bright
254.5Bright
264.5Bright
274.5Bright
284.5Bright
294.5Bright
304.5Bright
314.5Bright
Planning a trip in May

Hazard calendar for Kalutara

In seasonPeak

In May, Kalutara sits inside its cyclone season. The full year is below, with each hazard's peak months called out.

Kalutara sits in the North Indian Ocean cyclone zone; the season peaks May and October–November.

Cyclone
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is May a good time to visit Kalutara?

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

3.0
Sightseeing
12th-best month of the year
3.8
Beach & pool
9th-best month of the year

May is a weaker month for outdoor sightseeing in Kalutara.

What to pack for Kalutara in May

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

In May, Kalutara sees daytime highs around 29°C and nights near 26°C. Pack light clothes and rain gear. Worth having: sun protection. About 30 days see rain.

light clothesrain gearsun protection

Sea temperature near Kalutara in May

The nearest coast averages about 29°C in May — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in April at about 30°C and coldest in August near 28°C.

The water stays above 20°C all year — warm enough for a swim any month.

26°28°30°32°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan28Warm
Feb28Tropical
Mar29Tropical
Apr30Tropical
May29Tropical
Jun28Tropical
Jul28Warm
Aug28Warm
Sep28Warm
Oct28Tropical
Nov29Tropical
Dec28Tropical

UV index in Kalutara in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 12 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Kalutara peaks around April 17 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 10 (very high).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highApr 17UV 13Dec 21UV 10
UV index (midday)Level
Jan10Very high
Feb12Extreme
Mar12Extreme
Apr14Extreme
May12Extreme
Jun11Extreme
Jul11Extreme
Aug13Extreme
Sep13Extreme
Oct12Extreme
Nov11Extreme
Dec10Very high

Air quality in Kalutara 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 Kalutara is worst in January — around 84 µg/m³ PM2.5 (unhealthy), about 2.8× the cleanest month (July, 29 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0306090JanFebMarAprMayJunJulAugSepOctNovDecUnhealthyPoorModeratePoorUnhealthyJan 1483 µg/m³Jul 2129 µg/m³
PM2.5 (µg/m³)Level
Jan84Unhealthy
Feb78Unhealthy
Mar73Unhealthy
Apr62Unhealthy
May44Poor
Jun31Moderate
Jul29Moderate
Aug30Moderate
Sep35Poor
Oct52Poor
Nov74Unhealthy
Dec81Unhealthy
Location & terrain

Where is Kalutara?

Kalutara sits at 6.6°N, 80.0°E, 7 m above sea level, in Sri Lanka. The nearest listed city is Beruwala, 12 km away.

HomagamaMaharagamaDehiwala-Mount LaviniaSri Jayewardenepura Kotte

Topography around Kalutara

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

Within 3 km, the terrain around Kalutara has only modest variations in elevation — a maximum elevation change of 45 m around an average of 6 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 277 m; within 80 km, very significant variations in elevation — a maximum elevation change of 2,145 m.

The land around Kalutara is covered by water (48%) and trees (41%) within 3 km, water (48%) and trees (46%) within 16 km, and trees (60%) and water (37%) within 80 km.

3 km
45 m
16 km
277 m
80 km
2,145 m
treesgrasslandcroplandartificial surfaceswater
May weather nearby: Beruwala 12 km · Panadura 16 km · Bentota 18 km · Moratuwa 23 km · Homagama 29 km · Maharagama 30 km · Dehiwala-Mount Lavinia 30 km · Sri Jayewardenepura Kotte 34 km

Sri Lanka travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type D / G / M
230 V · 50 Hz
Prices
≈ 27% of US
price level, 2025
GDP per capita
$5,002
2025
Happiness
4.0 / 10
World Happiness, 2025
Safe drinking water
47%
of population, 2024
Homicide rate
3.3
per 100k, 2019
Road deaths
19.7
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Low
EF EPI 486
Religion
Buddhist 70%Hindu 13%Muslim 10%Roman Catholic 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 Kalutara (6.5831°, 79.9593°, elevation 7 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). 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. 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).