Harlingen weather in December

In December, Harlingen sees average daytime highs of 73°F and overnight lows near 55°F, with 1.3 in of precipitation across 5.5 wet days and about 10.4 hours of daylight. It is the 11th-warmest and 10th-wettest month of the year here.

Highs ease over the month, from about 75°F in the first days to 71°F by the end. The sky is clear or mostly clear about 35% of the time in December, and the air most often feels dry.

Daylight stretches from about 10 h 30 min at the start of December to 10 h 24 min by month's end. Set against the rest of the year, December is Harlingen's 11th-clearest and 8th-windiest month. For the whole year in context, see Harlingen's year-round climate.

Daytime high
73°
11th warmest
Overnight low
55°
2nd coldest
Precipitation
1.3 in
5.5 wet days
Daylight
10 h 24 min
7:16 AM – 5:38 PM
Cloud cover
58%
11th clearest
Wind
10 mph
8th windiest
Solar energy
2.91 kWh/m²
Travel score
7.4
out of 10

Harlingen is city in Cameron County, Texas, United States.

Density
630/km²
people per km²
Founded
1904

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 75°F in the first days to 71°F by the end.

A typical December day in Harlingen reaches about 73°F in the afternoon and slips back to 55°F overnight — a 18°F spread between the day's warmth and the night's chill. On most days the high lands between 59°F and 83°F. Set against its neighbours, December runs about 6°F cooler than November and on par with January.

40°60°80°151015202531
Avg high (°F)Avg low (°F)
17557
27557
37557
47556
57456
67456
77456
87456
97455
107355
117355
127355
137355
147355
157355
167354
177254
187254
197254
207254
217254
227253
237153
247153
257153
267153
277153
287153
297153
307153
317053

How December really feels in Harlingen

Once humidity and wind are folded in, December averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
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.

Harlingen weather by month

How December compares with the rest of the year at a glance. December is the 11th-warmest and 10th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan71° / 53°1.25.110.57.3
Feb75° / 57°1.04.911.17.6
Mar80° / 62°1.65.511.87.2
Apr85° / 68°1.75.512.65.7
May90° / 73°1.96.513.34.3
Jun94° / 77°2.38.913.63.1
Jul95° / 78°2.48.513.52.6
Aug95° / 78°2.19.412.92.5
Sep91° / 75°4.114.412.23.4
Oct86° / 68°2.77.911.45.5
Nov78° / 61°1.56.510.77.4
Dec73° / 55°1.35.510.47.4

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 35% 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 51%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15446
25248
35149
45050
54951
64951
74951
84753
94852
104852
114951
124951
135050
144951
155050
165050
175149
185050
195050
205050
214951
224852
234753
244753
254654
264654
274555
284456
294456
304456
314456

Chance of precipitation in December

Any precipitation

Harlingen gets around 1.3 in of rain and snow over 5.5 wet days in December. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 18% and peaks near 19% on the wettest days, and about 0 day brings snow.

0%10%20%30%151015202531
Rain chance (%)
116
216
316
416
516
616
716
816
916
1017
1117
1217
1318
1418
1518
1618
1718
1818
1918
2018
2119
2219
2319
2419
2519
2619
2719
2818
2918
3018
3118

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, December lands in the dry band about 52% of days. Sticky, muggy-or-worse air turns up on roughly 19% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1411517234
2421517224
3431517224
4441416224
5441416224
6461316213
7461316213
8471316213
9481216203
10491216203
11511216192
12511216192
13511216192
14521216182
15521216182
16531216172
17541216162
18541216162
19551216152
20561216142
21551316142
22561316132
23561316132
24571316122
25571316122
26561416122
27571416112
28571416112
29581416111
30581416111
31581416111

Wind in December

Winds average 10 mph in December.

Across December, daily wind ranges from about 10 mph on the calmest days to 10 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
110light breeze
210light breeze
310light breeze
410light breeze
510light breeze
610light breeze
710light breeze
810light breeze
910light breeze
1010light breeze
1110light breeze
1210light breeze
1310light breeze
1410light breeze
1510light breeze
1610light breeze
1710light breeze
1810light breeze
1910light breeze
2010light breeze
2110light breeze
2210light breeze
2310light breeze
2410light breeze
2510light breeze
2610light breeze
2710light breeze
2810light breeze
2910light breeze
3010light breeze
3110light breeze

Sunrise & sunset in December

DaylightNight

Daylight runs from about 10 h 30 min at the start of December to 10 h 24 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 7:06 AM to 7:23 AM, and sunset from 5:35 PM to 5:45 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
110.57:065:35
210.57:075:35
310.57:085:35
410.47:085:35
510.47:095:35
610.47:105:35
710.47:105:36
810.47:115:36
910.47:125:36
1010.47:125:36
1110.47:135:36
1210.47:145:37
1310.47:145:37
1410.47:155:37
1510.47:155:38
1610.47:165:38
1710.47:165:38
1810.47:175:39
1910.47:185:39
2010.47:185:40
2110.47:195:40
2210.47:195:41
2310.47:195:41
2410.47:205:41
2510.47:205:42
2610.47:215:43
2710.47:215:43
2810.47:225:44
2910.47:225:44
3010.47:225:45
3110.47:235:45

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 2.91 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 2.91 kWh/m² to a high of 6.72 kWh/m² in July across the year — December's 2.91 kWh/m² sits near the bottom.

01234151015202531
Solar energy (kWh/m²)Level
13.1Moderate
23.1Moderate
33.0Moderate
43.0Moderate
53.0Moderate
63.0Moderate
73.0Moderate
83.0Moderate
93.0Moderate
102.9Moderate
112.9Moderate
122.9Moderate
132.9Moderate
142.9Moderate
152.9Moderate
162.9Moderate
172.9Moderate
182.9Moderate
192.9Moderate
202.9Moderate
212.9Moderate
222.9Moderate
232.9Moderate
242.9Moderate
252.9Moderate
262.9Moderate
272.9Moderate
282.9Moderate
292.9Moderate
302.9Moderate
312.9Moderate
Planning a trip in December

Hazard calendar for Harlingen

In seasonPeak

None of Harlingen's seasonal hazards are active in December. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

Harlingen sits in the Atlantic hurricane belt; the season peaks August–October.

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

Is December a good time to visit Harlingen?

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

7.4
Sightseeing
2nd-best month of the year
5.5
Beach & pool
10th-best month of the year

December is one of the better times to visit Harlingen for general sightseeing.

What to pack for Harlingen in December

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

In December, Harlingen sees daytime highs around 73°F and nights near 55°F. Worth packing: light clothes. About 6 days see rain.

light clothes

Sea temperature near Harlingen in December

The nearest coast averages about 70°F 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 35 mi away) is warmest in September at about 84°F and coldest in February near 65°F.

It's comfortable for a long swim from Mar 22 to Dec 29 — about 9.3 months when the water holds above 68°F.

60°70°80°JanFebMarAprMayJunJulAugSepOctNovDeccoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°F)Comfort
Jan66Cool
Feb65Cool
Mar67Cool
Apr72Refreshing
May77Warm
Jun82Warm
Jul82Tropical
Aug83Tropical
Sep84Tropical
Oct81Warm
Nov75Refreshing
Dec70Refreshing

UV index in Harlingen in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Harlingen peaks around June 21 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 5 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecHighVery highExtremeVery highExtremeVery highHighJun 21UV 12Dec 22UV 5
UV index (midday)Level
Jan5Moderate
Feb7High
Mar8Very high
Apr11Extreme
May9Very high
Jun12Extreme
Jul11Extreme
Aug11Extreme
Sep10Very high
Oct8Very high
Nov6High
Dec5Moderate

Air quality in Harlingen 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 Harlingen is worst in July — around 25 µg/m³ PM2.5 (moderate), about 3.7× the cleanest month (October, 7 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1525 µg/m³Oct 247 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb9Good
Mar11Good
Apr13Moderate
May19Moderate
Jun20Moderate
Jul25Moderate
Aug18Moderate
Sep13Moderate
Oct7Good
Nov7Good
Dec9Good
Location & terrain

Where is Harlingen?

Harlingen sits at 26.2°N, 97.7°W, 39 ft above sea level, in United States. The nearest listed city is San Benito, 5.6 mi away.

Topography around Harlingen

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Harlingen.

Within 2 miles, the terrain around Harlingen has only modest variations in elevation — a maximum elevation change of 66 ft around an average of 43 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 82 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 446 ft.

The land around Harlingen is covered by artificial surfaces (56%) and trees (25%) within 2 miles, cropland (52%) and grassland (22%) within 10 miles, and cropland (34%), grassland (22%) and water (20%) within 50 miles.

2 miles
66 ft
10 miles
82 ft
50 miles
446 ft
treesshrubsgrasslandcroplandartificial surfacesbare terrainwaterwetland
December weather nearby: San Benito 5.6 mi · Mercedes 14 mi · Weslaco 19 mi · Donna 22 mi · Brownsville 24 mi · Heroica Matamoros 25 mi · Alamo 27 mi · Ciudad Río Bravo 28 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

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 Harlingen (26.1906°, -97.6961°, elevation 39 ft), 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).