Lancaster weather in December

In December, Lancaster sees average daytime highs of 44°F and overnight lows near 31°F, with 3.6 in of precipitation across 9.2 wet days and about 9.2 hours of daylight. It is the 10th-warmest and 7th-wettest month of the year here.

Highs ease over the month, from about 47°F in the first days to 41°F by the end. The sky is clear or mostly clear about 27% of the time in December, and the air most often feels dry.

Daylight stretches from about 9 h 24 min at the start of December to 9 h 12 min by month's end. Set against the rest of the year, December is Lancaster's 9th-clearest and 5th-windiest month. For the whole year in context, see Lancaster's year-round climate.

Daytime high
44°
10th warmest
Overnight low
31°
3rd coldest
Precipitation
3.6 in
9.2 wet days
Daylight
9 h 12 min
7:26 AM – 4:36 PM
Cloud cover
63%
9th clearest
Wind
8 mph
5th windiest
Solar energy
1.81 kWh/m²
Travel score
0.6
out of 10

Lancaster is city in central Lancaster County, Pennsylvania, United States.

Density
3,116/km²
people per km²
Founded
1730

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 47°F in the first days to 41°F by the end.

A typical December day in Lancaster reaches about 44°F in the afternoon and slips back to 31°F overnight — a 13°F spread between the day's warmth and the night's chill. On most days the high lands between 32°F and 56°F. Set against its neighbours, December runs about 10°F cooler than November and about 5°F warmer than January.

20°40°60°151015202531
Avg high (°F)Avg low (°F)
14834
24734
34734
44734
54633
64633
74533
84532
94532
104432
114432
124431
134431
144331
154331
164331
174331
184330
194330
204230
214230
224230
234229
244229
254229
264229
274229
284129
294129
304129
314128

How December really feels in Lancaster

Once humidity and wind are folded in, December averages 0 days that feel above 90°F and 31 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
31
wind chill below the day's low

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

Lancaster weather by month

How December compares with the rest of the year at a glance. December is the 10th-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan39° / 26°3.19.13.99.50.0
Feb42° / 27°2.993.810.40.3
Mar51° / 34°3.910.32.911.72.4
Apr63° / 45°3.610.30.3135.3
May72° / 55°3.611.4014.26.4
Jun81° / 64°3.711.1014.86.0
Jul85° / 69°3.911.1014.65.1
Aug83° / 67°3.410.3013.65.8
Sep76° / 60°4.39.3012.36.9
Oct65° / 48°3.68.40.110.96.0
Nov53° / 38°3.08.20.49.83.2
Dec44° / 31°3.69.22.39.20.6

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 27% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 15% of December, with mostly cloudy or overcast conditions the remaining 58%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14357
24258
34258
44258
54060
64060
74060
84060
94060
104060
114060
124060
134159
144159
154159
164159
174159
184258
194456
204456
214456
224456
234555
244654
254654
264555
274555
284555
294456
304456
314357

Chance of precipitation in December

Any precipitationSnow

Lancaster gets around 3.6 in of rain and snow over 9.2 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 30% and peaks near 32% on the wettest days, and about 2 days bring snow.

0%10%20%30%40%151015202531
Rain chance (%)Snow chance (%)
1315
2315
3315
4316
5316
6317
7327
8327
9328
10328
11318
12319
13319
14319
15319
16308
17308
18308
19298
20298
21298
22288
23288
24277
25277
26277
27277
28277
29278
30288
31288

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 99% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)
1982
2982
3982
4982
5991
6991
7991
8991
9991
10991
11991
12991
13991
14991
15991
16991
17991
18991
19991
20991
21991
22991
23991
24991
25991
26991
27991
28991
29991
30991
31991

Wind in December

Winds average 8 mph in December.

Across December, daily wind ranges from about 8 mph on the calmest days to 8 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
18light breeze
28light breeze
38light breeze
48light breeze
58light breeze
68light breeze
78light breeze
88light breeze
98light breeze
108light breeze
118light breeze
128light breeze
138light breeze
148light breeze
158light breeze
168light breeze
178light breeze
188light breeze
198light breeze
208light breeze
218light breeze
228light breeze
238light breeze
248light breeze
258light breeze
268light breeze
278light breeze
288light breeze
298light breeze
308light breeze
318light breeze

Sunrise & sunset in December

DaylightNight

Daylight runs from about 9 h 24 min at the start of December to 9 h 12 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 7:14 AM to 7:33 AM, and sunset from 4:36 PM to 4:44 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.47:144:36
29.37:154:36
39.37:164:36
49.37:174:35
59.37:184:35
69.37:194:35
79.37:204:35
89.27:204:35
99.27:214:35
109.27:224:35
119.27:234:35
129.27:244:36
139.27:244:36
149.27:254:36
159.27:264:36
169.27:264:36
179.27:274:37
189.27:284:37
199.27:284:37
209.27:294:38
219.27:294:38
229.27:304:39
239.27:304:39
249.27:314:40
259.27:314:40
269.27:314:41
279.27:324:41
289.27:324:42
299.27:324:43
309.27:324:43
319.27:334:44

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 1.81 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 1.81 kWh/m² to a high of 6.1 kWh/m² in June across the year — December's 1.81 kWh/m² sits near the bottom.

00.511.522.5151015202531
Solar energy (kWh/m²)Level
11.9Dim
21.9Dim
31.9Dim
41.9Dim
51.9Dim
61.8Dim
71.8Dim
81.8Dim
91.8Dim
101.8Dim
111.8Dim
121.8Dim
131.8Dim
141.8Dim
151.8Dim
161.8Dim
171.8Dim
181.8Dim
191.8Dim
201.8Dim
211.8Dim
221.8Dim
231.8Dim
241.8Dim
251.8Dim
261.8Dim
271.8Dim
281.8Dim
291.9Dim
301.9Dim
311.9Dim
Planning a trip in December

Is December a good time to visit Lancaster?

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

0.6
Sightseeing
10th-best month of the year
0.0
Beach & pool
10th-best month of the year

December is a weaker month for outdoor sightseeing in Lancaster.

What to pack for Lancaster in December

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

In December, Lancaster sees daytime highs around 44°F and nights near 31°F. Pack a warm layer. Worth having: a heavy coat and rain gear. About 9 days see rain.

a warm layera heavy coatrain gear

UV index in Lancaster in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 2. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Lancaster peaks around June 23 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateLowJun 23UV 9Dec 21UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May8Very high
Jun9Very high
Jul9Very high
Aug6High
Sep6High
Oct3Moderate
Nov3Moderate
Dec2Low

Air quality in Lancaster 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 Lancaster is worst in July — around 17 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (November, 8 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1417 µg/m³Nov 138 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb12Good
Mar13Moderate
Apr13Moderate
May15Moderate
Jun16Moderate
Jul17Moderate
Aug15Moderate
Sep12Good
Oct9Good
Nov8Good
Dec9Good
Location & terrain

Where is Lancaster?

Lancaster sits at 40.0°N, 76.3°W, 361 ft above sea level, in United States. The nearest listed city is Lebanon, 22 mi away.

Topography around Lancaster

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

Within 2 miles, the terrain around Lancaster has only modest variations in elevation — a maximum elevation change of 246 ft around an average of 348 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 725 ft; within 50 miles, large variations in elevation — a maximum elevation change of 1,991 ft.

The land around Lancaster is covered by trees (48%) and artificial surfaces (35%) within 2 miles, cropland (33%), trees (31%) and grassland (26%) within 10 miles, and trees (55%) within 50 miles.

2 miles
246 ft
10 miles
725 ft
50 miles
1,991 ft
treesgrasslandcroplandartificial surfaceswater
December weather nearby: Lebanon 22 mi · York 23 mi · Reading 29 mi · Bel Air North 34 mi · North Bel Air 35 mi · Harrisburg 35 mi · South Bel Air 35 mi · Bel Air South 37 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 Lancaster (40.0379°, -76.3055°, elevation 361 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).