Climate and monthly weather forecastWilliamsport, PA
Climate and monthly weather forecast
The climate of Williamsport
Classified under the Köppen climate classification as a humid continental climate, Williamsport, Pennsylvania experiences no dry season, with rainfall distributed evenly throughout the year. The city's geographical position exposes it to varying weather patterns all year round. Weather parameters such as temperature, humidity, rainfall, and daylight hours show significant changes as seasons transition.Temperature highs gradually rise from an average high of 30.6°F (-0.8°C) in January to a peak of 81.7°F (27.6°C) in July, before descending back to 36.7°F (2.6°C) by December. A similar trend occurs in temperature lows, with the coolest month being January at an average low of 18.9°F (-7.3°C), and July having the warmest nights at an average of 59.2°F (15.1°C).
In terms of humidity, the relative averages swing from 77% to 84%, reflecting a consistently high level of moisture in the air. Precipitation events are relatively frequent but moderate, with rainfall ranging between 0.94" (24mm) and 1.93" (49mm) monthly. The number of rainfall days falls between 7.5 days and 16.6 days in a month, indicating regular overcast conditions. This is further corroborated by the percentage of cloud cover, which varies from 35% to 60%.
Interestingly, Williamsport also experiences snowfall, averaging between 2.28" (58mm) and 0.1" (3mm). Snowfall primarily occurs from January to March and then briefly in November and December, with snowless skies from April to October.
The best time to visit Williamsport
Tourists interested in milder temperatures and less rainfall might find that the best time to visit Williamsport is between May and October. During this period, daytime temperatures range from 56.5°F (13.6°C) to 79.2°F (26.2°C), with significantly reduced rainfall levels, averaging from 1.5 to 1.85" (47mm). The length of daylight also reaches its maximum in these months, enhanced by sunshine hours averaging between 8.3 hours and 10.1 hours per day. Meanwhile, humidity levels drop slightly, resulting in more pleasant weather overall.The worst time to visit Williamsport
The colder months of January and February present the most challenging weather conditions. With the lowest average high and low temperatures, ranging from 18.9°F (-7.3°C) to 34.5°F (1.4°C), visitors can expect snowy and icy scenarios, particularly as snowfall reaches its peak within these months. Rainfall also consistently hovers around the 0.98" (25mm) mark with more frequent rainy days.Spring weather in Williamsport
Spring in Williamsport marks a steady rise in temperatures, with average highs ranging between 44.2°F (6.8°C) in March to 68.4°F (20.2°C) by May. Correspondingly, nighttime temperatures rise from 27.7°F (-2.4°C) to 48°F (8.9°C). While rainfall does increase during this period, from 1.1" (28mm) in March to 1.85" (47mm) in May, the length of daylight also notably extends from 12 hours to 14.5 hours.Summer weather in Williamsport
The summer months, June through August, promise warm sunny days with average highs peaking at 81.7°F (27.6°C) in July. Even nights remain warm, averaging between 54.7°F (12.6°C) and 59.2°F (15.1°C). Rainfall remains relatively constant around 1.57" (40mm) to 1.69" (43mm). The season is characterized by long, sunny days, with the longest day in June giving more than 15 hours of daylight and sunshine acquiring a peak prominence of 10.1 hours in July.Autumn weather in Williamsport
The autumn months in Williamsport witness a gradual decrease in temperatures from the high of 72.1°F (22.3°C) in September to 46.2°F (7.9°C) in November. The night temperature also descends quite noticeably from 51.4°F (10.8°C) to 32.4°F (0.2°C). Rainfall sees a slight decrease from September through November, maintaining an average of 1.44" (37mm). Sunshine hours also dwindle, contrasting the abundant sunshine of the summer, reaching as low as 5 hours per day in November.Winter weather in Williamsport
Winters in Williamsport are cold and frequently snowy. Daily average temperatures range from 30.6°F (-0.8°C) to 36.7°F (2.6°C), with nightly lows resting between 18.9°F (-7.3°C) and 26.6°F (-3°C). Snowfall is a common occurrence, especially in January, with an average accumulation of 2.13" (54mm). Daylight becomes scarce during this season, with the shortest day seeing only 9.3 hours of light, and sunshine hours can be as sparse as 3.7 hours per day.Weather in January
January is the start of the year and embraces Williamsport with a quintessential winter scene. The city encounters significant snowfall with an average snowfall depth of 2.13" (54mm) coupled with the lowest temperatures of the year. Weather in January »Weather in February
As Williamsport navigates through February, a slight increase in temperature is noticed though the winter chill still lingers. February is another month where snowfall is encountered, albeit slightly less than January at around 2.28" (58mm). Weather in February »Weather in March
March marks the onset of spring in Williamsport. The snow has mostly started to retreat, paving the way for a change in atmosphere with rainfall recordings standing at an average of 1.1" (28mm). The increases in temperature to a high of 44.2°F (6.8°C) and a low of 27.7°F (-2.4°C) bring a noticeable difference from the winter months. Weather in March »Weather in April
April in Williamsport sees a definitive spring vibe. A significant leap in temperature can be observed, culminating in a high of 56.5°F (13.6°C) and a low of 37.8°F (3.2°C). A noticeable transition from snowfall to rainfall transpires, with little to no snowfall registered and rainfall climbing to 1.93" (49mm). Weather in April »Weather in May
May introduces Williamsport to warmer temperatures, signifying the approaching summer. With average high temperatures reaching a comfortable 68.4°F (20.2°C), the outdoor scene starts bustling with people. Clouds get sparser, setting the stage for about 8.3 hours of sunshine on an average day. Weather in May »Weather in June
June welcomes the summer in Williamsport with a noticeable rise in temperatures. With the highest daylight hours recorded in a month reaching 15.1 hours, outdoor activity is at its peak. Temperatures continue to rise and settle around a high of 76.1°F (24.5°C). Weather in June »Weather in July
July brings forth the hottest weather conditions for Williamsport in the year. Fluctuations in temperature are minimal, with an average recorded high of 81.7°F (27.6°C), the highest for the year. Despite the consistent sunshine, the air clings to a high humidity level making conditions feel hotter than recorded. Weather in July »Weather in August
August in Williamsport continues the summer spell but brings a slight drop in temperature compared to July. The fading summer heat still allows for plenty of outdoor activities, with suitable climate conditions throughout the month. Weather in August »Weather in September
September signals the onset of autumn in Williamsport. Waning summer warmth leaves the climate pleasant, with an average temperature high of 72.1°F (22.3°C) during the day. This month marks a visible shift in the weather pattern as daylight hours start to shrink. Weather in September »Weather in October
October brings a soothing chill to Williamsport as the heart of autumn sets in. A sharp decline in temperature is noticed with an average high of 59.4°F (15.2°C). This month showcases the turning leaves of the Pennsylvania autumn, as vibrant colors paint the cityscape. Weather in October »Weather in November
November in Williamsport initiates the early onset of winter weather. With a discernable dip in temperatures, reaching a high of 46.2°F (7.9°C), residents prepare for the cold months ahead. The rainfall reduces to 0.94" (24mm), hinting at the imminent shift to wintery conditions. Weather in November »Weather in December
December graces Williamsport with a taste of winter magic. The city captures the charm of the season with a meaningful increase in snowfall, an average depth of 1.38" (35mm) recorded. The temperature dips to a chilly 36.7°F (2.6°C) high, adding to the festive freezing spirit. Weather in December »Updated: Jun 3, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Williamsport's coldest temperatures are experienced in January, with average high temperatures of 30.6°F (-0.8°C) and lows of 18.9°F (-7.3°C).
In Williamsport, during the entire year, the rain falls for 145.2 days and collects up to 16.57" (421mm) of precipitation.
January through April, October through December are months with snowfall.
In Williamsport, during the entire year, snow falls for 39.1 days and aggregates up to 7.56" (192mm) of snow.
January and February, with an average of 3.7h of sunshine, are months with the least sunshine.
The months with the lowest UV index are January through March, October through December, with an average maximum UV index of 2.
With an average relative humidity of 84%, February is the most humid month in Williamsport, Pennsylvania.
The month with the most snowfall is February, when snow falls for 10.1 days and typically aggregates up to 2.28" (58mm) of snow.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, and the time zone changes from EST to EDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from EDT to EST.
April and July, with an average relative humidity of 77%, are the least humid months.
The month with the most rainfall is April, when the rain falls for 15 days and typically aggregates up to 1.93" (49mm) of precipitation.
In Williamsport, Pennsylvania, snow does not fall in May through September.
With an average of 15h and 6min of daylight, June has the longest days of the year.
Williamsport's July weather, marked by an average high temperature of 81.7°F (27.6°C) and an average low temperature of 59.2°F (15.1°C), is the warmest in the year.
The month with the most sunshine is July, with an average of 10.1h of sunshine.
The month with the highest UV index is July, with an average maximum UV index of 6.
November is the month with the least rainfall. Rain falls for 8.6 days and accumulates 0.94" (24mm) of precipitation.
December has the shortest days of the year, with an average of 9h and 18min of daylight.
Average temperature
Williamsport, PA
The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is January (30.6°F).
The month with the highest average low temperature is July (59.2°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).
Average pressure
Williamsport, PA
- Average pressure in January:
30.09"Hg - Average pressure in February:
30.06"Hg - Average pressure in March:
30.08"Hg - Average pressure in April:
29.98"Hg - Average pressure in May:
30.01"Hg - Average pressure in June:
29.94"Hg
- Average pressure in July:
29.98"Hg - Average pressure in August:
30"Hg - Average pressure in September:
30.07"Hg - Average pressure in October:
30.03"Hg - Average pressure in November:
30.13"Hg - Average pressure in December:
30.09"Hg
The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed
Williamsport, PA
- Average wind speed in January:
7.5mph - Average wind speed in February:
7.3mph - Average wind speed in March:
7.5mph - Average wind speed in April:
7.5mph - Average wind speed in May:
6.2mph - Average wind speed in June:
5.8mph
- Average wind speed in July:
5mph - Average wind speed in August:
4.8mph - Average wind speed in September:
5.3mph - Average wind speed in October:
6.3mph - Average wind speed in November:
6.7mph - Average wind speed in December:
7mph
The windiest months (with the highest average wind speed) are January, March and April (7.5mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).
Average humidity
Williamsport, PA
The month with the highest relative humidity is February (84%).
The months with the lowest relative humidity are April and July (77%).
Average rainfall
Williamsport, PA
- Average rainfall in January:
0.98" - Average rainfall in February:
0.98" - Average rainfall in March:
1.1" - Average rainfall in April:
1.93" - Average rainfall in May:
1.85" - Average rainfall in June:
1.57"
The wettest month (with the highest rainfall) is April (1.93").
The driest month (with the least rainfall) is November (0.94").
Average rainfall days
Williamsport, PA
- Average rainfall days in January:
8.4 days - Average rainfall days in February:
7.5 days - Average rainfall days in March:
11 days - Average rainfall days in April:
15 days - Average rainfall days in May:
16.6 days - Average rainfall days in June:
14.7 days
- Average rainfall days in July:
15.8 days - Average rainfall days in August:
14 days - Average rainfall days in September:
11.2 days - Average rainfall days in October:
11.8 days - Average rainfall days in November:
8.6 days - Average rainfall days in December:
10.6 days
The month with the highest number of rainy days is May (16.6 days).
The month with the least rainy days is February (7.5 days).
Average snowfall
Williamsport, PA
The month with the highest snowfall is February (2.28").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days
Williamsport, PA
- Average snowfall days in January:
11.8 days - Average snowfall days in February:
10.1 days - Average snowfall days in March:
5.3 days - Average snowfall days in April:
0.9 days - Average snowfall days in May:
0.1 days - Average snowfall days in June:
0 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0 days - Average snowfall days in October:
0.3 days - Average snowfall days in November:
2.5 days - Average snowfall days in December:
8.1 days
The month with the highest number of snowfall days is January (11.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Williamsport, PA
- Average daylight in January:
9h and 36min - Average daylight in February:
10h and 36min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 18min - Average daylight in May:
14h and 30min - Average daylight in June:
15h and 6min
- Average daylight in July:
14h and 48min - Average daylight in August:
13h and 48min - Average daylight in September:
12h and 30min - Average daylight in October:
11h and 6min - Average daylight in November:
9h and 54min - Average daylight in December:
9h and 18min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in January:
3h and 42min - Average sunshine in February:
3h and 42min - Average sunshine in March:
5h and 54min - Average sunshine in April:
7h and 42min - Average sunshine in May:
8h and 18min - Average sunshine in June:
9h and 30min
- Average sunshine in July:
10h and 6min - Average sunshine in August:
9h and 48min - Average sunshine in September:
8h and 36min - Average sunshine in October:
5h and 6min - Average sunshine in November:
5h and 0min - Average sunshine in December:
3h and 54min
The month with the most sunshine is July (Average sunshine: 10h and 6min).
The months with the least sunshine are January and February (Average sunshine: 3h and 42min).
Average sunshine days
Williamsport, PA
- Average sunshine days in January:
14.4 days - Average sunshine days in February:
13.8 days - Average sunshine days in March:
16.2 days - Average sunshine days in April:
12.9 days - Average sunshine days in May:
11.8 days - Average sunshine days in June:
13 days
- Average sunshine days in July:
12.9 days - Average sunshine days in August:
14.8 days - Average sunshine days in September:
16.8 days - Average sunshine days in October:
16.5 days - Average sunshine days in November:
18.7 days - Average sunshine days in December:
15.5 days
The month with the most sunshine days is November (18.7 days).
The month with the least sunshine days is May (11.8 days).
Average UV index
Williamsport, PA
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, March, October, November and December (UV index 2).
Average cloud cover
Williamsport, PA
The months with the most cloud cover are January and February (Cloud cover 60).
The month with the least cloud cover is July (Cloud cover 35).
Average visibility
Williamsport, PA
The month with the highest visibility is April (6mi).
The month with the lowest visibility is September (4mi).
