Chambersburg weather in December

In December, Chambersburg sees average daytime highs of 41°F and overnight lows near 28°F, with 3.3 in of precipitation across 8.6 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 45°F in the first days to 39°F by the end. The sky is clear or mostly clear about 22% 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 Chambersburg's 11th-clearest and 5th-windiest month. For the whole year in context, see Chambersburg's year-round climate.

Daytime high
41°
10th warmest
Overnight low
28°
3rd coldest
Precipitation
3.3 in
8.6 wet days
Daylight
9 h 12 min
7:31 AM – 4:42 PM
Cloud cover
67%
11th clearest
Wind
7 mph
5th windiest
Solar energy
1.75 kWh/m²
Travel score
0.2
out of 10

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 45°F in the first days to 39°F by the end.

A typical December day in Chambersburg reaches about 41°F in the afternoon and slips back to 28°F overnight — a 13°F spread between the day's warmth and the night's chill. On most days the high lands between 30°F and 54°F. Set against its neighbours, December runs about 10°F cooler than November and about 4°F warmer than January.

20°40°60°151015202531
Avg high (°F)Avg low (°F)
14632
24532
34531
44431
54431
64431
74330
84330
94230
104229
114229
124229
134129
144129
154128
164128
174128
184028
194028
204027
214027
224027
234027
244027
254027
264026
274026
283926
293926
303926
313926

How December really feels in Chambersburg

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.

Chambersburg 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
Jan37° / 23°3.194.39.50.0
Feb40° / 25°2.78.54.310.40.2
Mar49° / 32°3.810.53.211.72.1
Apr62° / 43°3.6110.4135.0
May71° / 52°3.812.4014.26.1
Jun80° / 61°3.510.8014.86.3
Jul84° / 66°3.510.1014.55.5
Aug82° / 65°2.89.1013.66.2
Sep75° / 57°4.09.3012.36.9
Oct63° / 46°3.38.20.210.95.8
Nov51° / 36°3.18.20.99.82.7
Dec41° / 28°3.38.62.79.20.2

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 22% 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 65%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13763
23763
33565
43565
53466
63466
73367
83367
93268
103268
113268
123268
133367
143367
153367
163466
173565
183664
193664
203664
213664
223664
233862
243862
253763
263763
273763
283763
293664
303664
313763

Chance of precipitation in December

Any precipitationSnow

Chambersburg gets around 3.3 in of rain and snow over 8.6 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 29% and peaks near 31% on the wettest days, and about 3 days bring snow.

0%10%20%30%40%151015202531
Rain chance (%)Snow chance (%)
1317
2317
3318
4318
5308
6309
7309
83010
93010
103010
112911
122911
132911
142911
152910
162910
172910
182910
19299
20289
21289
22278
23278
24268
25268
26268
27268
28268
29278
30279
31279

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 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)
1991
2991
3991
4991
5991
61000
71000
81000
91000
101000
111000
121000
131000
141000
151000
161000
171000
181000
191000
201000
211000
221000
231000
241000
251000
261000
271000
281000
291000
301000
311000

Wind in December

Winds average 7 mph in December.

Across December, daily wind ranges from about 7 mph on the calmest days to 7 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm
317calm

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 7:19 AM to 7:38 AM, and sunset from 4:42 PM to 4:50 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.47:194:42
29.47:204:41
39.37:214:41
49.37:224:41
59.37:234:41
69.37:244:41
79.37:254:41
89.37:254:41
99.27:264:41
109.27:274:41
119.27:284:41
129.27:294:41
139.27:294:41
149.27:304:42
159.27:314:42
169.27:314:42
179.27:324:43
189.27:334:43
199.27:334:43
209.27:344:44
219.27:344:44
229.27:354:44
239.27:354:45
249.27:364:45
259.27:364:46
269.27:364:47
279.27:374:47
289.27:374:48
299.27:374:48
309.27:384:49
319.27:384:50

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 1.75 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 1.75 kWh/m² to a high of 6.08 kWh/m² in June across the year — December's 1.75 kWh/m² sits near the bottom.

00.511.522.5151015202531
Solar energy (kWh/m²)Level
11.8Dim
21.8Dim
31.8Dim
41.8Dim
51.8Dim
61.8Dim
71.8Dim
81.7Dim
91.7Dim
101.7Dim
111.7Dim
121.7Dim
131.7Dim
141.7Dim
151.7Dim
161.7Dim
171.7Dim
181.7Dim
191.7Dim
201.7Dim
211.7Dim
221.8Dim
231.8Dim
241.8Dim
251.8Dim
261.8Dim
271.8Dim
281.8Dim
291.8Dim
301.8Dim
311.8Dim
Planning a trip in December

Is December a good time to visit Chambersburg?

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

0.2
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 Chambersburg.

What to pack for Chambersburg in December

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

In December, Chambersburg sees daytime highs around 41°F and nights near 28°F. Pack a warm layer and a heavy coat. Worth having: rain gear. About 9 days see rain.

a warm layera heavy coatrain gear

UV index in Chambersburg 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 Chambersburg peaks around June 22 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 20 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 22UV 9Dec 20UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May8Very high
Jun9Very high
Jul9Very high
Aug7High
Sep6High
Oct3Moderate
Nov2Moderate
Dec2Low

Air quality in Chambersburg 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 Chambersburg is worst in July — around 16 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (November, 7 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1316 µg/m³Nov 137 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb11Good
Mar12Good
Apr12Good
May14Moderate
Jun16Moderate
Jul16Moderate
Aug14Moderate
Sep11Good
Oct8Good
Nov7Good
Dec8Good
Location & terrain

Where is Chambersburg?

Chambersburg sits at 39.9°N, 77.7°W, 617 ft above sea level, in United States. The nearest listed city is Hagerstown, 21 mi away.

Topography around Chambersburg

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

Within 2 miles, the terrain around Chambersburg has only modest variations in elevation — a maximum elevation change of 220 ft around an average of 659 ft above sea level; within 10 miles, significant variations in elevation — a maximum elevation change of 1,877 ft; within 50 miles, large variations in elevation — a maximum elevation change of 2,802 ft.

The land around Chambersburg is covered by trees (30%), artificial surfaces (29%) and grassland (26%) within 2 miles, trees (40%), cropland (34%) and grassland (21%) within 10 miles, and trees (64%) within 50 miles.

2 miles
220 ft
10 miles
1,877 ft
50 miles
2,802 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
December weather nearby: Hagerstown 21 mi · Carlisle 31 mi · Martinsburg 37 mi · Hanover 37 mi · Frederick 39 mi · Ballenger Creek 41 mi · Westminster 43 mi · Harrisburg 47 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 Chambersburg (39.9376°, -77.6611°, elevation 617 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).