Ratnapura weather in May

In May, Ratnapura sees average daytime highs of 27°C and overnight lows near 22°C, with 310 mm of rain across 29.6 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 5th-wettest month of the year here.

Day-to-day highs hold fairly steady near 27°C through the month. The sky is clear or mostly clear about 1% of the time in May, and the air most often feels oppressive.

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 Ratnapura's 7th-clearest and 5th-windiest month. For the whole year in context, see Ratnapura's year-round climate.

Daytime high
27°
4th warmest
Overnight low
22°
12th coldest
Rainfall
310 mm
29.6 wet days
Daylight
12 h 18 min
5:56 AM – 6:14 PM
Cloud cover
84%
7th clearest
Wind
5 km/h
5th windiest
Solar energy
4.84 kWh/m²
Travel score
3.4
out of 10

Ratnapura is city in Sabaragamuwa, Sri Lanka.

Density
2,392/km²
people per km²

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 27°C through the month.

A typical May day in Ratnapura reaches about 27°C in the afternoon and slips back to 22°C overnight — a 5°C spread between the day's warmth and the night's chill. On most days the high lands between 26°C and 28°C. Set against its neighbours, May runs about 1°C cooler than April and about 1°C warmer than June.

20°23°25°28°30°151015202531
Avg high (°C)Avg low (°C)
12822
22822
32822
42822
52822
62822
72822
82822
92822
102822
112822
122722
132722
142722
152722
162722
172722
182722
192722
202722
212722
222722
232722
242722
252722
262722
272722
282722
292722
302722
312722

Ratnapura weather by month

How May compares with the rest of the year at a glance. May is the 4th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan27° / 19°30822.811.74.5
Feb28° / 19°27920.511.84.6
Mar28° / 20°30927.4123.7
Apr28° / 21°4682912.13.3
May27° / 22°31029.612.33.4
Jun26° / 22°26727.912.43.6
Jul26° / 21°24628.512.33.7
Aug26° / 21°22828.312.23.7
Sep26° / 21°24626123.9
Oct27° / 21°49727.511.93.8
Nov27° / 20°66126.911.73.8
Dec27° / 20°51526.111.64.0

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 1% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 10% of May, with mostly cloudy or overcast conditions the remaining 89%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
11783
21684
31684
41684
51486
61486
71486
81486
91387
101288
111288
121288
131288
141189
151189
161189
171189
181090
191090
201090
21991
22991
23991
24892
25892
26892
27892
28793
29793
30793
31793

Chance of precipitation in May

Any precipitation

Ratnapura gets around 310 mm of rain over 29.6 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 96% on the wettest days.

0%20%40%60%80%100%151015202531
Rain chance (%)
195
295
395
495
595
695
795
895
995
1096
1196
1296
1396
1496
1596
1696
1796
1896
1996
2096
2196
2296
2396
2496
2596
2696
2795
2895
2995
3095
3195

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

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

0%25%50%75%100%151015202531
Muggy (%)Oppressive (%)
1397
2397
3397
4397
5397
6397
7397
8397
9397
10397
11397
12298
13298
14298
15298
16298
17298
18298
19298
20298
21298
22298
23298
24298
25397
26397
27397
28496
29496
30595
31595

Wind in May

Winds average 5 km/h in May.

Across May, daily wind ranges from about 4 km/h on the calmest days to 6 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
14calm
24calm
34calm
44calm
54calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
196calm
206calm
216calm
226calm
236calm
246calm
256calm
266calm
276calm
286calm
296calm
306calm
316calm

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 5:59 AM to 5:55 AM, and sunset from 6:13 PM to 6:16 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.25:596:13
212.25:586:13
312.25:586:13
412.25:586:13
512.35:586:13
612.35:576:13
712.35:576:13
812.35:576:13
912.35:576:13
1012.35:566:13
1112.35:566:13
1212.35:566:13
1312.35:566:13
1412.35:566:13
1512.35:566:14
1612.35:566:14
1712.35:556:14
1812.35:556:14
1912.35:556:14
2012.35:556:14
2112.35:556:15
2212.35:556:15
2312.35:556:15
2412.35:556:15
2512.35:556:15
2612.35:556:15
2712.35:556:16
2812.35:556:16
2912.45:556:16
3012.45:556:16
3112.45:556:16

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 4.84 kWh/m².

For context, solar energy here swings from a low near 4.23 kWh/m² to a high of 6.05 kWh/m² in March across the year — May's 4.84 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.2Bright
25.1Bright
35.1Bright
45.1Bright
55.0Bright
65.0Bright
75.0Bright
85.0Bright
95.0Bright
105.0Bright
114.9Bright
124.9Bright
134.9Bright
144.9Bright
154.9Bright
164.9Bright
174.8Bright
184.8Bright
194.8Bright
204.8Bright
214.8Bright
224.8Bright
234.8Bright
244.7Bright
254.7Bright
264.7Bright
274.7Bright
284.7Bright
294.7Bright
304.7Bright
314.7Bright
Planning a trip in May

Hazard calendar for Ratnapura

In seasonPeak

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

Ratnapura 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 Ratnapura?

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

3.4
Sightseeing
11th-best month of the year
3.6
Beach & pool
10th-best month of the year

May is a weaker month for outdoor sightseeing in Ratnapura.

What to pack for Ratnapura in May

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

In May, Ratnapura sees daytime highs around 27°C and nights near 22°C. Pack light clothes and rain gear. Worth having: sun protection. About 30 days see rain.

light clothesrain gearsun protection

Sea temperature near Ratnapura 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 at the nearest coast (about 59 km away) 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 Ratnapura in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Ratnapura peaks around April 17 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 17 at about 10 (extreme).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeApr 17UV 14Dec 17UV 10
UV index (midday)Level
Jan11Extreme
Feb14Extreme
Mar13Extreme
Apr14Extreme
May13Extreme
Jun11Extreme
Jul12Extreme
Aug13Extreme
Sep13Extreme
Oct13Extreme
Nov11Extreme
Dec10Extreme

Air quality in Ratnapura 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 Ratnapura 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 Ratnapura?

Ratnapura sits at 6.7°N, 80.4°E, 73 m above sea level, in Sri Lanka. The nearest listed city is Hatton, 31 km away.

HattonHanwella IhalaHomagamaKalutaraBeruwalaNuwara EliyaBentotaPanadura

Topography around Ratnapura

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

Within 3 km, the terrain around Ratnapura has significant variations in elevation — a maximum elevation change of 364 m around an average of 79 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,947 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,500 m.

The land around Ratnapura is covered by trees (93%) within 3 km, trees (98%) within 16 km, and trees (79%) within 80 km.

3 km
364 m
16 km
1,947 m
80 km
2,500 m
treesgrasslandcroplandartificial surfaceswater
May weather nearby: Hatton 31 km · Hanwella Ihala 43 km · Homagama 48 km · Kalutara 50 km · Beruwala 52 km · Nuwara Eliya 53 km · Bentota 54 km · Panadura 55 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 Ratnapura (6.6858°, 80.4036°, elevation 73 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).