Allen weather in December

In December, Allen sees average daytime highs of 57°F and overnight lows near 40°F, with 3.6 in of precipitation across 7.1 wet days and about 9.9 hours of daylight. It is the 11th-warmest and 6th-wettest month of the year here.

Highs ease over the month, from about 60°F in the first days to 55°F by the end. The sky is clear or mostly clear about 45% of the time in December, and the air most often feels dry.

Daylight stretches from about 10 hours at the start of December to 9 h 48 min by month's end. Set against the rest of the year, December is Allen's 7th-clearest and 7th-windiest month. For the whole year in context, see Allen's year-round climate.

Daytime high
57°
11th warmest
Overnight low
40°
2nd coldest
Precipitation
3.6 in
7.1 wet days
Daylight
9 h 48 min
7:28 AM – 5:18 PM
Cloud cover
50%
7th clearest
Wind
9 mph
7th windiest
Solar energy
2.56 kWh/m²
Travel score
4.5
out of 10

Allen is city in Collin County, Texas, United States.

Density
1,431/km²
people per km²
Founded
1953

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 60°F in the first days to 55°F by the end.

A typical December day in Allen reaches about 57°F in the afternoon and slips back to 40°F overnight — a 18°F spread between the day's warmth and the night's chill. On most days the high lands between 43°F and 71°F. Set against its neighbours, December runs about 8°F cooler than November and about 2°F warmer than January.

20°40°60°80°151015202531
Avg high (°F)Avg low (°F)
16142
26042
36042
46042
55941
65941
75941
85841
95840
105840
115840
125840
135740
145740
155739
165739
175739
185639
195639
205639
215638
225638
235638
245638
255538
265538
275538
285538
295538
305538
315538

How December really feels in Allen

Once humidity and wind are folded in, December averages 0 days that feel above 90°F and 10 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
10
wind chill below the day's low

The story in December is cold — wind chill drags the overnight "feels like" below the raw low.

Allen weather by month

How December compares with the rest of the year at a glance. December is the 11th-warmest and 6th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan56° / 38°2.86.90.410.14.1
Feb60° / 41°2.97.50.510.85.0
Mar67° / 48°3.99.20.211.76.4
Apr75° / 56°4.38.4012.87.2
May82° / 65°5.411.1013.76.0
Jun89° / 73°3.48.4014.14.3
Jul94° / 76°1.860143.2
Aug94° / 76°2.15.3013.23.3
Sep87° / 69°2.86.3012.25.3
Oct77° / 58°3.97.8011.27.4
Nov66° / 47°3.67.10.110.36.6
Dec57° / 40°3.67.10.29.94.5

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 45% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 11% of December, with mostly cloudy or overcast conditions the remaining 44%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15941
25941
35941
45842
55743
65842
75743
85644
95644
105644
115545
125545
135545
145545
155545
165644
175644
185644
195644
205545
215545
225545
235545
245545
255446
265446
275545
285545
295446
305446
315545

Chance of precipitation in December

Any precipitationSnow

Allen gets around 3.6 in of rain and snow over 7.1 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 23% and peaks near 25% on the wettest days, and about 0 day brings snow.

0%10%20%30%40%151015202531
Rain chance (%)Snow chance (%)
1221
2231
3231
4231
5231
6241
7241
8241
9240
10250
11240
12240
13240
14240
15240
16240
17241
18231
19231
20231
21231
22221
23221
24221
25221
26221
27222
28222
29222
30222
31222

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 92% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)
18965
28965
38965
48965
58965
69064
79154
89154
99253
109253
119253
129352
139352
149442
159541
169541
179541
189541
199541
209541
219541
229541
239541
249541
259451
269352
279352
289352
299352
309352
319253

Wind in December

Winds average 9 mph in December.

Across December, daily wind ranges from about 9 mph on the calmest days to 9 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
19light breeze
29light breeze
39light breeze
49light breeze
59light breeze
69light breeze
79light breeze
89light breeze
99light breeze
109light breeze
119light breeze
129light breeze
139light breeze
149light breeze
159light breeze
169light breeze
179light breeze
189light breeze
199light breeze
209light breeze
219light breeze
229light breeze
239light breeze
249light breeze
259light breeze
269light breeze
279light breeze
289light breeze
299light breeze
309light breeze
319light breeze

Sunrise & sunset in December

DaylightNight

Daylight runs from about 10 hours at the start of December to 9 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 12 minutes over December. Sunrise moves from 7:17 AM to 7:35 AM, and sunset from 5:16 PM to 5:25 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
110.07:175:16
210.07:185:16
39.97:195:15
49.97:205:15
59.97:205:16
69.97:215:16
79.97:225:16
89.97:235:16
99.97:235:16
109.97:245:16
119.97:255:16
129.87:265:16
139.87:265:17
149.87:275:17
159.87:285:17
169.87:285:18
179.87:295:18
189.87:295:18
199.87:305:19
209.87:305:19
219.87:315:20
229.87:315:20
239.87:325:20
249.87:325:21
259.87:335:21
269.87:335:22
279.87:335:23
289.87:345:23
299.87:345:24
309.87:345:24
319.87:355:25

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 2.56 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 2.56 kWh/m² to a high of 6.79 kWh/m² in July across the year — December's 2.56 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.7Moderate
22.7Moderate
32.7Moderate
42.6Moderate
52.6Moderate
62.6Moderate
72.6Moderate
82.6Moderate
92.6Moderate
102.6Moderate
112.5Moderate
122.5Moderate
132.5Moderate
142.5Moderate
152.5Moderate
162.5Moderate
172.5Moderate
182.5Moderate
192.5Moderate
202.5Moderate
212.5Moderate
222.5Moderate
232.5Moderate
242.5Moderate
252.5Moderate
262.6Moderate
272.6Moderate
282.6Moderate
292.6Moderate
302.6Moderate
312.6Moderate
Planning a trip in December

Is December a good time to visit Allen?

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

4.5
Sightseeing
8th-best month of the year
0.1
Beach & pool
11th-best month of the year

December is a reasonable time to visit Allen for sightseeing.

What to pack for Allen in December

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

In December, Allen sees daytime highs around 57°F and nights near 40°F. Worth packing: a warm layer. About 7 days see rain.

a warm layer

UV index in Allen in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 3 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Allen peaks around July 17 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 3 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateJul 17UV 10Dec 21UV 3
UV index (midday)Level
Jan3Moderate
Feb5Moderate
Mar6High
Apr9Very high
May9Very high
Jun10Very high
Jul10Extreme
Aug10Very high
Sep8Very high
Oct6High
Nov4Moderate
Dec3Moderate

Air quality in Allen 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 Allen is worst in July — around 19 µg/m³ PM2.5 (moderate), about 2.6× the cleanest month (October, 8 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1519 µg/m³Oct 248 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb8Good
Mar10Good
Apr11Good
May14Moderate
Jun16Moderate
Jul19Moderate
Aug15Moderate
Sep11Good
Oct8Good
Nov8Good
Dec8Good
Location & terrain

Where is Allen?

Allen sits at 33.1°N, 96.7°W, 659 ft above sea level, in United States. The nearest listed city is Plano, 6.2 mi away.

Topography around Allen

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

Within 2 miles, the terrain around Allen has only modest variations in elevation — a maximum elevation change of 144 ft around an average of 653 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 328 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 735 ft.

The land around Allen is covered by artificial surfaces (67%) within 2 miles, artificial surfaces (44%), grassland (26%) and trees (20%) within 10 miles, and grassland (48%) and trees (25%) within 50 miles.

2 miles
144 ft
10 miles
328 ft
50 miles
735 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
December weather nearby: Plano 6.2 mi · Murphy 6.8 mi · McKinney 7.5 mi · Frisco 9.3 mi · Wylie 9.9 mi · Sachse 9.9 mi · Richardson 11 mi · Prosper 12 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 Allen (33.1032°, -96.6706°, elevation 659 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. 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).