Williamsport weather in January

In January, Williamsport sees average daytime highs of 33°F and overnight lows near 20°F, with 3.2 in of precipitation across 10.1 wet days and about 9.4 hours of daylight. It is the 12th-warmest and 11th-wettest month of the year here.

Day-to-day highs hold fairly steady near 33°F through the month. The sky is clear or mostly clear about 16% of the time in January, and the air most often feels dry.

Daylight stretches from about 9 h 06 min at the start of January to 9 h 48 min by month's end. Set against the rest of the year, January is Williamsport's 11th-clearest and 2nd-windiest month. For the whole year in context, see Williamsport's year-round climate.

Daytime high
33°
12th warmest
Overnight low
20°
1st coldest
Precipitation
3.2 in
10.1 wet days
Daylight
9 h 18 min
7:37 AM – 4:57 PM
Cloud cover
73%
11th clearest
Wind
7 mph
2nd windiest
Solar energy
1.9 kWh/m²
Travel score
0.0
out of 10

Williamsport is city in and county seat of Lycoming County, Pennsylvania, United States.

Density
1,196/km²
people per km²
Founded
1769

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in January

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 33°F through the month.

A typical January day in Williamsport reaches about 33°F in the afternoon and slips back to 20°F overnight — a 14°F spread between the day's warmth and the night's chill. On most days the high lands between 20°F and 46°F. Set against its neighbours, January runs about 5°F cooler than December and about 3°F cooler than February.

20°40°151015202531
Avg high (°F)Avg low (°F)
13523
23522
33522
43522
53522
63522
73421
83421
93421
103421
113420
123420
133320
143320
153319
163319
173319
183319
193318
203218
213218
223218
233218
243318
253318
263318
273318
283318
293318
303318
313418

How January really feels in Williamsport

Once humidity and wind are folded in, January 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
28 feel bitter (≤ 14°F)

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

Williamsport weather by month

How January compares with the rest of the year at a glance. January is the 12th-warmest and 11th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan33° / 20°3.210.16.39.40.0
Feb36° / 21°2.79.15.610.30.0
Mar46° / 29°3.9114.411.71.1
Apr58° / 40°4.111.81.213.14.1
May68° / 49°4.013.2014.35.8
Jun77° / 58°4.211.9014.96.4
Jul81° / 63°3.711.5014.76.2
Aug80° / 62°3.710.5013.76.5
Sep72° / 54°4.69.5012.36.8
Oct60° / 43°3.9100.310.94.9
Nov48° / 34°3.591.49.71.8
Dec38° / 26°3.510.14.69.10.0

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 16% of the time in January.

Beyond those clear spells, partly cloudy skies cover about 11% of January, with mostly cloudy or overcast conditions the remaining 73%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
12872
22872
32872
42872
52773
62773
72674
82674
92674
102674
112674
122674
132674
142674
152674
162674
172674
182575
192575
202575
212575
222674
232773
242773
252773
262872
272872
282971
293070
303169
313169

Chance of precipitation in January

Any precipitationSnow

Williamsport gets around 3.2 in of rain and snow over 10.1 wet days in January. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 32% and peaks near 35% on the wettest days, and about 6 days bring snow.

0%10%20%30%40%50%151015202531
Rain chance (%)Snow chance (%)
13215
23216
33317
43317
53418
63418
73519
83519
93520
103520
113521
123521
133521
143421
153422
163422
173322
183322
193222
203222
213122
223122
233022
243021
253021
262921
272921
282921
292920
302920
312920

Humidity in January

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, January 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 (%)
1100
2100
3100
4100
5100
6100
7100
8100
9100
10100
11100
12100
13100
14100
15100
16100
17100
18100
19100
20100
21100
22100
23100
24100
25100
26100
27100
28100
29100
30100
31100

Wind in January

Winds average 7 mph in January.

Across January, 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 January

DaylightNight

Daylight runs from about 9 h 06 min at the start of January to 9 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 42 minutes over January. Sunrise moves from 7:39 AM to 7:28 AM, and sunset from 4:43 PM to 5:15 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.17:394:43
29.17:394:44
39.17:394:45
49.17:394:46
59.17:394:47
69.17:394:47
79.27:394:48
89.27:394:49
99.27:394:50
109.27:394:51
119.27:394:52
129.27:384:53
139.37:384:54
149.37:384:55
159.37:384:56
169.37:374:57
179.47:374:58
189.47:365:00
199.47:365:01
209.47:355:02
219.57:355:03
229.57:345:04
239.57:345:05
249.67:335:06
259.67:335:08
269.67:325:09
279.67:315:10
289.77:305:11
299.77:305:12
309.77:295:14
319.87:285:15

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 1.9 kWh/m².

For context, solar energy here swings from a low near 1.56 kWh/m² to a high of 5.98 kWh/m² in June across the year — January's 1.9 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
11.6Dim
21.6Dim
31.6Dim
41.6Dim
51.7Dim
61.7Dim
71.7Dim
81.7Dim
91.7Dim
101.7Dim
111.8Dim
121.8Dim
131.8Dim
141.8Dim
151.9Dim
161.9Dim
171.9Dim
181.9Dim
192.0Dim
202.0Moderate
212.0Moderate
222.1Moderate
232.1Moderate
242.1Moderate
252.2Moderate
262.2Moderate
272.2Moderate
282.3Moderate
292.3Moderate
302.3Moderate
312.4Moderate
Planning a trip in January

Is January a good time to visit Williamsport?

Our two travel scores rate January 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
9th-best month of the year

January is a weaker month for outdoor sightseeing in Williamsport.

What to pack for Williamsport in January

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

In January, Williamsport sees daytime highs around 33°F and nights near 20°F. Pack a warm layer and a heavy coat. Worth having: rain gear. About 10 days see rain.

a warm layera heavy coatrain gear

UV index in Williamsport in January

LowModerateHighVery highExtreme

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

Under clear skies, the midday UV index in Williamsport 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 1 (low).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJun 23UV 9Dec 21UV 1
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar5Moderate
Apr6High
May8Very high
Jun9Very high
Jul9Very high
Aug6High
Sep6High
Oct3Moderate
Nov2Moderate
Dec1Low

Air quality in Williamsport in January

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where January falls, not just the annual average.

Air quality in Williamsport is worst in July — around 15 µg/m³ PM2.5 (moderate), about 2.4× the cleanest month (November, 7 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1415 µg/m³Nov 127 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb10Good
Mar11Good
Apr11Good
May13Moderate
Jun14Moderate
Jul15Moderate
Aug13Moderate
Sep11Good
Oct7Good
Nov7Good
Dec8Good
Location & terrain

Where is Williamsport?

Williamsport sits at 41.2°N, 77.0°W, 518 ft above sea level, in United States. The nearest listed city is Back Mountain, 53 mi away.

Topography around Williamsport

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

Within 2 miles, the terrain around Williamsport has significant variations in elevation — a maximum elevation change of 1,148 ft around an average of 686 ft above sea level; within 10 miles, significant variations in elevation — a maximum elevation change of 1,585 ft; within 50 miles, large variations in elevation — a maximum elevation change of 2,228 ft.

The land around Williamsport is covered by trees (48%) and artificial surfaces (29%) within 2 miles, trees (68%) within 10 miles, and trees (79%) within 50 miles.

2 miles
1,148 ft
10 miles
1,585 ft
50 miles
2,228 ft
treesgrasslandcroplandartificial surfaceswater
January weather nearby: Back Mountain 53 mi · State College 55 mi · Hazleton 57 mi · Wilkes-Barre 58 mi · Elmira 60 mi · Harrisburg 67 mi · Lebanon 70 mi · Scranton 70 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 Williamsport (41.2412°, -77.0011°, elevation 518 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).