Kalmunai weather in September

In September, Kalmunai sees average daytime highs of 31°C and overnight lows near 26°C, with 67 mm of rain across 13.7 wet days and about 12 hours of daylight. It is the 5th-warmest and 7th-wettest month of the year here.

Day-to-day highs hold fairly steady near 31°C through the month. The sky is clear or mostly clear about 14% of the time in September, and the air most often feels oppressive.

Daylight stretches from about 12 h 06 min at the start of September to 11 h 54 min by month's end. Set against the rest of the year, September is Kalmunai's 6th-clearest and 11th-windiest month. For the whole year in context, see Kalmunai's year-round climate.

Daytime high
31°
5th warmest
Overnight low
26°
8th coldest
Rainfall
67 mm
13.7 wet days
Daylight
12 hours
5:56 AM – 5:58 PM
Cloud cover
71%
6th clearest
Wind
8 km/h
11th windiest
Solar energy
5.97 kWh/m²
Travel score
4.0
out of 10

Kalmunai is human settlement.

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

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 31°C through the month.

A typical September day in Kalmunai reaches about 31°C in the afternoon and slips back to 26°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 29°C and 32°C. Set against its neighbours, September runs on par with August and about 1°C warmer than October.

25°28°30°33°35°151015202530
Avg high (°C)Avg low (°C)
13127
23127
33127
43127
53127
63127
73127
83127
93127
103127
113127
123127
133126
143126
153126
163126
173126
183126
193126
203126
213126
223126
233126
243126
253126
263026
273026
283026
293026
303026

How September really feels in Kalmunai

Once humidity and wind are folded in, September averages 30 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
30
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

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

Kalmunai weather by month

How September compares with the rest of the year at a glance. September is the 5th-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan27° / 24°18617.811.65.3
Feb28° / 24°951311.85.8
Mar29° / 25°609.911.95.7
Apr30° / 26°7013.412.24.5
May31° / 27°5911.612.34.0
Jun32° / 27°326.612.44.0
Jul32° / 27°317.612.44.0
Aug32° / 27°429.312.24.1
Sep31° / 26°6713.7124.0
Oct29° / 26°16420.811.83.8
Nov28° / 25°28024.711.73.9
Dec27° / 24°31022.511.64.5

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 14% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 19% of September, with mostly cloudy or overcast conditions the remaining 67%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
12872
22872
32872
42971
52971
63169
73268
83268
93367
103367
113466
123565
133565
143565
153664
163565
173565
183664
193664
203664
213466
223367
233367
243466
253367
263367
273268
283367
293367
303466

Chance of precipitation in September

Any precipitation

Kalmunai gets around 67 mm of rain over 13.7 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 45% and peaks near 55% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
137
238
339
439
540
640
741
841
941
1041
1141
1241
1341
1442
1543
1643
1744
1845
1946
2047
2148
2249
2351
2452
2553
2654
2754
2855
2955
3055

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the oppressive band about 74% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Muggy (%)Oppressive (%)Miserable (%)
117623
217623
317524
417425
517425
617326
717326
817326
917227
1017326
1117326
1217326
1317326
1417326
1517326
1607426
1707426
1807426
1907426
2007426
2107426
2207426
2307525
2407525
2507525
2607525
2707525
2807525
2907624
3007624

Wind in September

Winds average 8 km/h in September.

Across September, daily wind ranges from about 8 km/h on the calmest days to 8 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
18calm
28calm
38calm
48calm
58calm
68calm
78calm
88calm
98calm
108calm
118calm
128calm
138calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
288calm
298calm
308calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 06 min at the start of September to 11 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 12 minutes over September. Sunrise moves from 5:58 AM to 5:54 AM, and sunset from 6:07 PM to 5:50 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.15:586:07
212.15:586:06
312.15:586:06
412.15:586:05
512.15:586:04
612.15:576:04
712.15:576:03
812.15:576:03
912.15:576:02
1012.15:576:02
1112.15:576:01
1212.15:566:01
1312.15:566:00
1412.15:565:59
1512.05:565:59
1612.05:565:58
1712.05:565:58
1812.05:555:57
1912.05:555:56
2012.05:555:56
2112.05:555:55
2212.05:555:55
2312.05:555:54
2412.05:555:54
2512.05:545:53
2612.05:545:52
2712.05:545:52
2812.05:545:51
2911.95:545:51
3011.95:545:50

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5.97 kWh/m².

For context, solar energy here swings from a low near 4 kWh/m² to a high of 6.24 kWh/m² in March across the year — September's 5.97 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
16.0Intense
26.0Intense
36.0Intense
46.0Intense
56.0Intense
66.0Intense
76.0Intense
86.0Intense
96.0Intense
106.0Intense
116.0Intense
126.0Intense
136.0Intense
146.0Intense
156.0Intense
166.0Intense
176.0Intense
186.0Intense
196.0Bright
206.0Bright
216.0Bright
225.9Bright
235.9Bright
245.9Bright
255.9Bright
265.8Bright
275.8Bright
285.8Bright
295.8Bright
305.8Bright
Planning a trip in September

Hazard calendar for Kalmunai

In seasonPeak

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

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

Kalmunai's monsoon runs October–January, when most of the year's rain falls.

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

Is September a good time to visit Kalmunai?

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

4.0
Sightseeing
7th-best month of the year
5.9
Beach & pool
8th-best month of the year

September is a reasonable time to visit Kalmunai for sightseeing.

What to pack for Kalmunai in September

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

In September, Kalmunai sees daytime highs around 31°C and nights near 26°C. Pack light clothes and rain gear. Worth having: sun protection. About 14 days see rain.

light clothesrain gearsun protection

Sea temperature near Kalmunai in September

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

The sea offshore is warmest in May at about 30°C and coldest in January near 27°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
Jan27Warm
Feb28Warm
Mar29Tropical
Apr30Tropical
May30Tropical
Jun30Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct29Tropical
Nov29Tropical
Dec28Warm

UV index in Kalmunai in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September 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 Kalmunai peaks around April 19 at about 14 (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.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeApr 19UV 14Dec 21UV 10
UV index (midday)Level
Jan10Extreme
Feb12Extreme
Mar13Extreme
Apr14Extreme
May14Extreme
Jun11Extreme
Jul11Extreme
Aug13Extreme
Sep13Extreme
Oct12Extreme
Nov11Extreme
Dec10Very high

Air quality in Kalmunai in September

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Kalmunai is worst in May — around 25 µg/m³ PM2.5 (moderate), and holds fairly steady the rest of the year.

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateMay 2125 µg/m³Dec 2118 µg/m³
PM2.5 (µg/m³)Level
Jan19Moderate
Feb19Moderate
Mar20Moderate
Apr19Moderate
May25Moderate
Jun23Moderate
Jul23Moderate
Aug23Moderate
Sep22Moderate
Oct22Moderate
Nov20Moderate
Dec18Moderate
Location & terrain

Where is Kalmunai?

Kalmunai sits at 7.4°N, 81.8°E, 10 m above sea level, in Sri Lanka. The nearest listed city is Ampara, 21 km away.

BatticaloaEravur TownPottuvilVakaraiBadullaEllaPolonnaruwa

Topography around Kalmunai

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

Within 3 km, the terrain around Kalmunai has only modest variations in elevation — a maximum elevation change of 13 m around an average of 2 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 62 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,357 m.

The land around Kalmunai is covered by water (43%) within 3 km, water (53%) and cropland (30%) within 16 km, and water (43%) and trees (38%) within 80 km.

3 km
13 m
16 km
62 m
80 km
1,357 m
treesgrasslandcroplandartificial surfacesbare terrainwaterwetlandmangroves
September weather nearby: Ampara 21 km · Batticaloa 37 km · Eravur Town 48 km · Pottuvil 59 km · Vakarai 92 km · Badulla 98 km · Ella 105 km · Polonnaruwa 109 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 Kalmunai (7.409°, 81.8347°, elevation 10 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).