Sanya weather in December

In December, Sanya sees average daytime highs of 24°C and overnight lows near 19°C, with 26 mm of rain across 3 wet days and about 10.9 hours of daylight. It is the 10th-warmest and 9th-wettest month of the year here.

Highs ease over the month, from about 25°C in the first days to 23°C by the end. The sky is clear or mostly clear about 44% of the time in December, and the air most often feels muggy.

Daylight stretches from about 11 hours at the start of December to 10 h 54 min by month's end. Set against the rest of the year, December is Sanya's 4th-clearest and 1st-windiest month. For the whole year in context, see Sanya's year-round climate.

Daytime high
24°
10th warmest
Overnight low
19°
3rd coldest
Rainfall
26 mm
3 wet days
Daylight
10 h 54 min
7:11 AM – 6:05 PM
Cloud cover
49%
4th clearest
Wind
18 km/h
1st windiest
Solar energy
3.79 kWh/m²
Travel score
8.2
out of 10

Sanya is prefecture-level city in Hainan, China.

Air quality
Elevated
PM2.5 15.5 µg/m³ · 2018
Density
537/km²
people per km²

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

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 25°C in the first days to 23°C by the end.

A typical December day in Sanya reaches about 24°C in the afternoon and slips back to 19°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 21°C and 26°C. Set against its neighbours, December runs about 2°C cooler than November and about 1°C warmer than January.

15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
12521
22521
32521
42521
52520
62520
72420
82420
92420
102420
112420
122420
132420
142419
152419
162419
172419
182419
192419
202319
212319
222319
232319
242319
252319
262319
272319
282319
292319
302319
312319

How December really feels in Sanya

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.

Sanya weather by month

How December compares with the rest of the year at a glance. December is the 10th-warmest and 9th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan23° / 19°122.3118.2
Feb24° / 19°102.511.48.2
Mar25° / 22°183.811.97.9
Apr28° / 24°538.612.46.6
May29° / 26°1391912.84.3
Jun30° / 27°21222.213.13.4
Jul29° / 26°28023133.6
Aug29° / 26°26124.412.63.5
Sep29° / 26°25822.312.13.8
Oct28° / 24°1821411.65.7
Nov26° / 22°545.611.17.5
Dec24° / 19°26310.98.2

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 44% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 22% of December, with mostly cloudy or overcast conditions the remaining 34%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
17228
27129
37030
46832
56733
66634
76436
86337
96238
106238
116139
126139
136040
146139
156139
166238
176337
186337
196535
206535
216733
226733
236832
246832
256931
266931
277030
287030
297129
307129
317129

Chance of precipitation in December

Any precipitation

Sanya gets around 26 mm of rain over 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 10% and peaks near 13% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%151015202531
Rain chance (%)
113
213
312
412
512
612
712
812
912
1012
1113
1212
1312
1412
1512
1611
1711
1810
1910
209
219
228
238
247
257
267
277
286
296
306
316

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, December lands in the muggy band about 32% of days. Sticky, muggy-or-worse air turns up on roughly 43% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
15132337221
25142336210
35142436200
46152436190
56162536180
66162536170
76172635150
87172635140
97182635140
108182634130
119192634120
1210192634110
1311192633110
1411202633100
1512202632100
1613202632100
171420263290
181420263190
191520263190
201520273080
211620273070
221620282970
231620292960
241720292960
251620302950
261620312940
271620322940
281519333040
291419333030
301419333130
311319343130

Wind in December

Winds average 18 km/h in December, the windiest month of the year.

Across December, daily wind ranges from about 17 km/h on the calmest days to 18 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202531
Wind speed (km/h)Feels
118light breeze
218light breeze
318light breeze
418light 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
1818light breeze
1918light 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 December

DaylightNight

Daylight runs from about 11 hours at the start of December to 10 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 6 minutes over December. Sunrise moves from 7:02 AM to 7:18 AM, and sunset from 6:01 PM to 6:13 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.07:026:01
211.07:036:01
311.07:036:02
411.07:046:02
511.07:056:02
611.07:056:02
710.97:066:02
810.97:066:03
910.97:076:03
1010.97:086:03
1110.97:086:04
1210.97:096:04
1310.97:096:04
1410.97:106:05
1510.97:106:05
1610.97:116:05
1710.97:116:06
1810.97:126:06
1910.97:126:07
2010.97:136:07
2110.97:136:08
2210.97:146:08
2310.97:146:09
2410.97:156:09
2510.97:156:10
2610.97:166:10
2710.97:166:11
2810.97:166:11
2910.97:176:12
3010.97:176:12
3110.97:186:13

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 3.79 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 3.79 kWh/m² to a high of 5.82 kWh/m² in April across the year — December's 3.79 kWh/m² sits near the bottom.

01234151015202531
Solar energy (kWh/m²)Level
13.9Moderate
23.9Moderate
33.9Moderate
43.9Moderate
53.9Moderate
63.8Moderate
73.8Moderate
83.8Moderate
93.8Moderate
103.8Moderate
113.8Moderate
123.7Moderate
133.7Moderate
143.7Moderate
153.7Moderate
163.7Moderate
173.7Moderate
183.7Moderate
193.7Moderate
203.8Moderate
213.8Moderate
223.8Moderate
233.8Moderate
243.8Moderate
253.8Moderate
263.8Moderate
273.8Moderate
283.9Moderate
293.9Moderate
303.9Moderate
313.9Moderate
Planning a trip in December

Hazard calendar for Sanya

In seasonPeak

In December, Sanya sits inside its pacific typhoon season. The full year is below, with each hazard's peak months called out.

Sanya sits in the Pacific typhoon belt; the season peaks July–October.

Sanya's monsoon runs May–October, when most of the year's rain falls.

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

Is December a good time to visit Sanya?

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

8.2
Sightseeing
1st-best month of the year
6.8
Beach & pool
4th-best month of the year

December is one of the better times to visit Sanya for general sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Sanya in December

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

In December, Sanya sees daytime highs around 24°C and nights near 19°C. Worth packing: light clothes. About 3 days see rain.

light clothes

Sea temperature near Sanya in December

The nearest coast averages about 25°C in December — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 19 km away) is warmest in June at about 29°C and coldest in February near 23°C.

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

22°24°26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan23Refreshing
Feb23Refreshing
Mar24Warm
Apr26Warm
May28Tropical
Jun29Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct28Warm
Nov26Warm
Dec25Warm

UV index in Sanya in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Sanya peaks around August 11 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 16 at about 7 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeVery highHighAug 11UV 13Dec 16UV 7
UV index (midday)Level
Jan8Very high
Feb10Very high
Mar11Extreme
Apr11Extreme
May11Extreme
Jun12Extreme
Jul13Extreme
Aug13Extreme
Sep11Extreme
Oct10Very high
Nov8Very high
Dec7High

Air quality in Sanya 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 Sanya is worst in December — around 23 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (August, 11 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Sanya's WHO annual average of 15.5 µg/m³.

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateDec 1922 µg/m³Aug 1411 µg/m³
PM2.5 (µg/m³)Level
Jan20Moderate
Feb19Moderate
Mar17Moderate
Apr15Moderate
May11Good
Jun12Good
Jul11Good
Aug11Good
Sep11Good
Oct18Moderate
Nov18Moderate
Dec23Moderate
Location & terrain

Where is Sanya?

Sanya sits at 18.3°N, 109.5°E, 1 m above sea level, in China. The nearest listed city is An Hải, 278 km away.

Topography around Sanya

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

Within 3 km, the terrain around Sanya has only modest variations in elevation — a maximum elevation change of 203 m around an average of 24 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 610 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,775 m.

The land around Sanya is covered by trees (42%), artificial surfaces (32%) and water (22%) within 3 km, water (45%) and trees (41%) within 16 km, and trees (50%) and water (45%) within 80 km.

3 km
203 m
16 km
610 m
80 km
1,775 m
treesgrasslandcroplandartificial surfacesbare terrainwater
December weather nearby: An Hải 278 km · Da Nang 279 km · Sơn Trà 279 km · Thanh Khê 280 km · Hòa Cường 283 km · Hương Thủy 284 km · Hue 285 km · Cẩm Lệ 285 km

China travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type A / I
220 V · 50 Hz
Prices
≈ 47% of US
price level, 2025
GDP per capita
$13,862
2025
Happiness
6.1 / 10
World Happiness, 2025
Homicide rate
0.5
per 100k, 2020
Road deaths
17.4
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Low
EF EPI 464
Religion
unaffiliated 52%folk religion 22%Buddhist 18%Christian 5%

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 Sanya (18.2543°, 109.5095°, elevation 1 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).