Ko Lanta weather in December

In December, Ko Lanta sees average daytime highs of 28°C and overnight lows near 26°C, with 105 mm of rain across 12.3 wet days and about 11.6 hours of daylight. It is the 9th-warmest and 9th-wettest month of the year here.

Day-to-day highs hold fairly steady near 28°C through the month. The sky is clear or mostly clear about 18% of the time in December, and the air most often feels oppressive.

Daylight stretches from about 11 h 36 min at the start of December to 11 h 36 min by month's end. Set against the rest of the year, December is Ko Lanta's 5th-clearest and 2nd-windiest month. For the whole year in context, see Ko Lanta's year-round climate.

Daytime high
28°
9th warmest
Overnight low
26°
2nd coldest
Rainfall
105 mm
12.3 wet days
Daylight
11 h 36 min
6:33 AM – 6:07 PM
Cloud cover
71%
5th clearest
Wind
18 km/h
2nd windiest
Solar energy
4.84 kWh/m²
Travel score
5.4
out of 10

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 28°C through the month.

A typical December day in Ko Lanta reaches about 28°C in the afternoon and slips back to 26°C overnight — a 2°C spread between the day's warmth and the night's chill. On most days the high lands between 27°C and 29°C. Set against its neighbours, December runs on par with November and on par with January.

20°23°25°28°30°151015202531
Avg high (°C)Avg low (°C)
12826
22826
32826
42826
52826
62826
72826
82826
92826
102826
112826
122826
132826
142826
152826
162826
172826
182826
192826
202826
212826
222826
232826
242826
252826
262826
272826
282826
292826
302826
312826

How December really feels in Ko Lanta

Once humidity and wind are folded in, December 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

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

Ko Lanta weather by month

How December compares with the rest of the year at a glance. December is the 9th-warmest and 9th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan28° / 26°466.311.66.2
Feb29° / 26°25411.86.3
Mar29° / 27°8310.911.95.4
Apr29° / 27°14819.912.24.1
May29° / 27°25825.212.33.5
Jun29° / 27°22921.912.43.8
Jul29° / 27°22722.112.43.9
Aug28° / 27°27022.612.24.0
Sep28° / 26°30224.4123.8
Oct28° / 26°32728.311.83.6
Nov28° / 26°2232311.74.2
Dec28° / 26°10512.311.65.4

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 18% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 13% of December, with mostly cloudy or overcast conditions the remaining 69%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
12773
22773
32773
42872
52971
62971
72971
82971
93070
103070
113169
123169
133169
143169
153169
163169
173268
183268
193268
203268
213268
223268
233466
243367
253466
263466
273565
283565
293565
303664
313763

Chance of precipitation in December

Any precipitation

Ko Lanta gets around 105 mm of rain over 12.3 wet days in December. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 40% and peaks near 60% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)
160
258
356
454
553
651
750
849
947
1046
1145
1243
1342
1441
1540
1639
1738
1836
1935
2034
2133
2232
2331
2430
2529
2629
2728
2828
2927
3027
3127

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, December lands in the oppressive band about 89% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Muggy (%)Oppressive (%)Miserable (%)
128315
228315
328414
428513
528513
628612
728711
828810
92899
102908
112917
122926
133916
143925
153925
164924
174924
185923
195923
206922
216922
227912
238902
248902
259892
269892
279892
2810882
2910882
3010882
3110882

Wind in December

Winds average 18 km/h in December.

Across December, daily wind ranges from about 17 km/h on the calmest days to 19 km/h at its breeziest. It stays fairly steady from day to day.

0510152025151015202531
Wind speed (km/h)Feels
117light breeze
217light breeze
317light breeze
417light breeze
518light breeze
618light breeze
718light breeze
818light breeze
918light breeze
1018light breeze
1118light breeze
1218light breeze
1318light breeze
1418light breeze
1518light breeze
1618light breeze
1718light breeze
1819light breeze
1919light breeze
2019light breeze
2119light breeze
2219light breeze
2319light breeze
2419light breeze
2519light breeze
2619light breeze
2719light breeze
2819light breeze
2919light breeze
3019light breeze
3119light breeze

Sunrise & sunset in December

DaylightNight

Daylight runs from about 11 h 36 min at the start of December to 11 h 36 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 0 minutes over December. Sunrise moves from 6:26 AM to 6:40 AM, and sunset from 6:01 PM to 6:14 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.66:266:01
211.66:266:01
311.66:276:02
411.66:276:02
511.66:286:02
611.66:286:03
711.66:286:03
811.66:296:04
911.66:296:04
1011.66:306:04
1111.66:306:05
1211.66:316:05
1311.66:316:05
1411.66:326:06
1511.66:326:06
1611.66:336:07
1711.66:336:07
1811.66:346:08
1911.66:346:08
2011.66:356:09
2111.66:356:09
2211.66:366:09
2311.66:366:10
2411.66:376:10
2511.66:376:11
2611.66:386:11
2711.66:386:12
2811.66:396:12
2911.66:396:13
3011.66:396:13
3111.66:406:14

Solar energy in December

Daily solar energy (kWh/m²)

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

For context, solar energy here swings from a low near 4.66 kWh/m² to a high of 6.42 kWh/m² in March across the year — December's 4.84 kWh/m² sits near the bottom.

0246151015202531
Solar energy (kWh/m²)Level
14.6Bright
24.6Bright
34.6Bright
44.7Bright
54.7Bright
64.7Bright
74.7Bright
84.7Bright
94.7Bright
104.8Bright
114.8Bright
124.8Bright
134.8Bright
144.8Bright
154.8Bright
164.9Bright
174.9Bright
184.9Bright
194.9Bright
204.9Bright
214.9Bright
225.0Bright
235.0Bright
245.0Bright
255.0Bright
265.0Bright
275.0Bright
285.0Bright
295.1Bright
305.1Bright
315.1Bright
Planning a trip in December

Hazard calendar for Ko Lanta

In seasonPeak

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

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

Ko Lanta's rainy season runs April–November, when most of the year's rain falls.

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

Is December a good time to visit Ko Lanta?

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

5.4
Sightseeing
3rd-best month of the year
6.3
Beach & pool
4th-best month of the year

December is a reasonable time to visit Ko Lanta for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Ko Lanta in December

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

In December, Ko Lanta sees daytime highs around 28°C and nights near 26°C. Pack light clothes. Worth having: rain gear and sun protection. About 12 days see rain.

light clothesrain gearsun protection

Sea temperature near Ko Lanta in December

The nearest coast averages about 29°C in December — 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 29°C.

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

28°30°32°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan29Tropical
Feb29Tropical
Mar30Tropical
Apr30Tropical
May30Tropical
Jun30Tropical
Jul30Tropical
Aug30Tropical
Sep29Tropical
Oct29Tropical
Nov29Tropical
Dec29Tropical

UV index in Ko Lanta in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 10 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Ko Lanta peaks around February 22 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near November 22 at about 10 (extreme).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeFeb 22UV 13Nov 22UV 10
UV index (midday)Level
Jan11Extreme
Feb13Extreme
Mar13Extreme
Apr13Extreme
May12Extreme
Jun12Extreme
Jul11Extreme
Aug13Extreme
Sep13Extreme
Oct12Extreme
Nov10Extreme
Dec10Extreme

Air quality in Ko Lanta in December

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Ko Lanta is worst in April — around 16 µg/m³ PM2.5 (moderate), and holds fairly steady the rest of the year.

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

01020JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodGoodModerateApr 1115 µg/m³Aug 2011 µg/m³
PM2.5 (µg/m³)Level
Jan15Moderate
Feb14Moderate
Mar15Moderate
Apr16Moderate
May13Moderate
Jun13Moderate
Jul13Moderate
Aug11Good
Sep12Moderate
Oct12Good
Nov12Good
Dec13Moderate
Location & terrain

Where is Ko Lanta?

Ko Lanta sits at 7.5°N, 99.1°E, 0 m above sea level, in Thailand. The nearest listed city is Ko Phi Phi, 42 km away.

Topography around Ko Lanta

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

Within 3 km, the terrain around Ko Lanta has significant variations in elevation — a maximum elevation change of 481 m around an average of 77 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 487 m; within 80 km, large variations in elevation — a maximum elevation change of 1,003 m.

The land around Ko Lanta is covered by trees (53%) and water (41%) within 3 km, water (82%) within 16 km, and water (59%) and trees (36%) within 80 km.

3 km
481 m
16 km
487 m
80 km
1,003 m
treesgrasslandartificial surfaceswatermangroves
December weather nearby: Ko Phi Phi 42 km · Trang 58 km · Krabi 63 km · Ao Nang 65 km · Huai Yot 67 km · Ban Ko Sire 83 km · Ban Talat Yai 85 km · Phuket 86 km

Thailand travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type A / B / C
230 V · 50 Hz
Prices
≈ 31% of US
price level, 2025
GDP per capita
$8,057
2025
Happiness
6.3 / 10
World Happiness, 2025
Homicide rate
4.8
per 100k, 2011
Road deaths
32.2
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Very low
EF EPI 402
Religion
Buddhist 93%Muslim 5%Christian 1%other 1%

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 Ko Lanta (7.5336°, 99.0865°, elevation 0 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).