New Castle weather in December

In December, New Castle sees average daytime highs of 39°F and overnight lows near 27°F, with 3.5 in of precipitation across 11.9 wet days and about 9.1 hours of daylight. It is the 10th-warmest and 10th-wettest month of the year here.

Highs ease over the month, from about 42°F in the first days to 37°F by the end. The sky is clear or mostly clear about 11% of the time in December, and the air most often feels dry.

Daylight stretches from about 9 h 18 min at the start of December to 9 h 06 min by month's end. Set against the rest of the year, December is New Castle's 11th-clearest and 4th-windiest month. For the whole year in context, see New Castle's year-round climate.

Daytime high
39°
10th warmest
Overnight low
27°
3rd coldest
Precipitation
3.5 in
11.9 wet days
Daylight
9 h 06 min
7:46 AM – 4:50 PM
Cloud cover
79%
11th clearest
Wind
8 mph
4th windiest
Solar energy
1.44 kWh/m²
Travel score
0.0
out of 10

New Castle is city in and the county seat of Lawrence County, Pennsylvania, United States.

Density
1,012/km²
people per km²
Founded
1802

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 42°F in the first days to 37°F by the end.

A typical December day in New Castle reaches about 39°F in the afternoon and slips back to 27°F overnight — a 12°F spread between the day's warmth and the night's chill. On most days the high lands between 26°F and 53°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)
14331
24330
34230
44229
54229
64129
74129
84028
94028
104028
114027
123927
133927
143927
153926
163826
173826
183826
193826
203826
213825
223825
233725
243725
253725
263725
273725
283724
293724
303724
313724

How December really feels in New Castle

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.

New Castle weather by month

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

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan35° / 21°3.612.88.69.40.0
Feb38° / 22°2.810.96.610.40.0
Mar47° / 30°4.012.74.411.71.4
Apr60° / 41°4.614.21.513.14.2
May69° / 50°4.414.2014.35.7
Jun77° / 59°4.813.5014.96.2
Jul81° / 63°4.113.3014.66.0
Aug80° / 62°3.711013.66.5
Sep73° / 55°4.010.2012.36.7
Oct61° / 44°3.611.40.210.94.9
Nov49° / 34°3.510.72.39.71.9
Dec39° / 27°3.511.95.79.10.0

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 11% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 9% of December, with mostly cloudy or overcast conditions the remaining 80%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
12377
22179
32179
42179
52080
62080
72080
82080
92080
102080
111882
121882
131981
141981
151981
161981
172080
182080
192080
202080
212080
222080
232080
242080
252080
262080
272179
282278
292278
302080
311981

Chance of precipitation in December

Any precipitationSnow

New Castle gets around 3.5 in of rain and snow over 11.9 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 39% and peaks near 41% on the wettest days, and about 6 days bring snow.

0%10%20%30%40%50%151015202531
Rain chance (%)Snow chance (%)
14114
24115
34116
44116
54117
64118
74118
84119
94119
104019
114020
124020
133919
143919
153819
163819
173819
183819
193718
203718
213718
223718
233718
243718
253718
263818
273819
283819
293920
303920
314021

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
6991
7991
8991
9991
10991
11991
12991
13991
14991
15991
161000
171000
181000
191000
201000
211000
221000
231000
241000
251000
261000
271000
281000
291000
301000
311000

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 18 min at the start of December to 9 h 06 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 7:33 AM to 7:52 AM, and sunset from 4:49 PM to 4:57 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.37:334:49
29.27:344:49
39.27:354:49
49.27:364:49
59.27:374:49
69.27:384:48
79.27:394:48
89.17:404:48
99.17:404:48
109.17:414:48
119.17:424:49
129.17:434:49
139.17:444:49
149.17:444:49
159.17:454:49
169.17:464:50
179.17:464:50
189.17:474:50
199.17:474:51
209.07:484:51
219.07:484:51
229.07:494:52
239.07:494:52
249.07:504:53
259.17:504:53
269.17:514:54
279.17:514:55
289.17:514:55
299.17:514:56
309.17:524:56
319.17:524:57

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 1.44 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 1.44 kWh/m² to a high of 5.96 kWh/m² in June across the year — December's 1.44 kWh/m² sits near the bottom.

00.511.522.5151015202531
Solar energy (kWh/m²)Level
11.6Dim
21.5Dim
31.5Dim
41.5Dim
51.5Dim
61.5Dim
71.5Dim
81.5Dim
91.5Dim
101.4Dim
111.4Dim
121.4Dim
131.4Dim
141.4Dim
151.4Dim
161.4Dim
171.4Dim
181.4Dim
191.4Dim
201.4Dim
211.4Dim
221.4Dim
231.4Dim
241.4Dim
251.4Dim
261.4Dim
271.4Dim
281.5Dim
291.5Dim
301.5Dim
311.5Dim
Planning a trip in December

Is December a good time to visit New Castle?

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

0.0
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 New Castle.

What to pack for New Castle in December

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

In December, New Castle sees daytime highs around 39°F and nights near 27°F. Pack a warm layer and a heavy coat. Worth having: rain gear. About 12 days see rain.

a warm layera heavy coatrain gear

UV index in New Castle 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 New Castle peaks around June 22 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 2 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJun 22UV 9Dec 22UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar4Moderate
Apr6High
May8Very high
Jun9Very high
Jul9Very high
Aug7Very high
Sep6High
Oct3Moderate
Nov2Moderate
Dec2Low

Air quality in New Castle 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 New Castle is worst in July — around 16 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (November, 7 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1216 µg/m³Nov 137 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb10Good
Mar11Good
Apr11Good
May14Moderate
Jun15Moderate
Jul16Moderate
Aug14Moderate
Sep11Good
Oct7Good
Nov7Good
Dec8Good
Location & terrain

Where is New Castle?

New Castle sits at 41.0°N, 80.3°W, 853 ft above sea level, in United States. The nearest listed city is Boardman, 17 mi away.

Topography around New Castle

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

Within 2 miles, the terrain around New Castle has only modest variations in elevation — a maximum elevation change of 430 ft around an average of 988 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 732 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,089 ft.

The land around New Castle is covered by trees (56%), grassland (22%) and artificial surfaces (20%) within 2 miles, trees (58%) and grassland (25%) within 10 miles, and trees (69%) within 50 miles.

2 miles
430 ft
10 miles
732 ft
50 miles
1,089 ft
treesgrasslandcroplandartificial surfaceswater
December weather nearby: Boardman 17 mi · Hermitage 17 mi · Youngstown 17 mi · Austintown 23 mi · Niles 25 mi · Cranberry Township 25 mi · Warren 29 mi · Allison Park 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 New Castle (41.0037°, -80.347°, elevation 853 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).