Last updated: January 18, 2025
The climate of Pennsylvania, United States, is characterized by a diverse range of Köppen-Geiger climate classes, including Dfb (humid continental), Dfa (hot summer humid continental), Cfa (humid subtropical), and Cfb (oceanic). The state experiences a significant temperature variation throughout the year, with minimum temperatures plunging to -29°C (-21°F) in January, while average annual temperatures hover around a mild 12°C (53°F). In contrast, the summer months can see maximum temperatures soar to a sweltering 39°C (103°F) in August, showcasing the climatic extremes that define Pennsylvania's weather patterns.
Pennsylvania’s temperature patterns reveal distinct seasonal fluctuations, with winter months characterized by extreme cold; January and February see minimum temperatures plummet to as low as -29°C (-21°F) and -26°C (-15°F), respectively. As spring approaches, March and April gradually warm, experiencing average temperatures rising from 5°C (41°F) to 10°C (51°F) and maximums peaking at 31°C (88°F) in March. The transition into summer brings higher warmth and humidity, with average temperatures in June reaching 21°C (70°F) and peaks of up to 39°C (103°F) in August, highlighting a stark contrast to the preceding months. As the year progresses into fall, temperatures begin to moderate again; October averages drop to 14°C (57°F) while late November can see lows of -26°C (-15°F), bringing the cycle back to the frigid extremes of winter.
Pennsylvania's climate showcases significant temperature variations across its cities. In Gettysburg, temperatures range from a frigid minimum of -17°C (2°F) in January to a sweltering maximum of 36°C (97°F) in July. For more detailed information, explore the monthly temperature in Gettysburg. Pittsburgh experiences similar extremes, with January lows of -22°C (-8°F) and July highs reaching 35°C (96°F), as detailed on the monthly temperature in Pittsburgh page. Meanwhile, Philadelphia sees temperatures from -17°C (1°F) in January to an oppressive 37°C (99°F) in July. Further insights can be found at monthly temperature in Philadelphia.
Pennsylvania experiences a varied precipitation pattern throughout the year, with high rainfall amounts concentrated in the spring and early summer months. The state's wettest month is May, which records an average of 137 mm (5.4 in) of rain over approximately 14 days. This is closely followed by April and July, with 115 mm (4.5 in) and 136 mm (5.4 in) respectively. Winter months, while generally drier, still contribute significant precipitation, particularly in February with 109 mm (4.3 in), reflecting the transition from snow to rain as temperatures begin to rise.
In addition to total precipitation, the frequency of rainy days is notable in Pennsylvania's climate. January and February see about 10 to 13 rainy days, adding to the winter chill, while spring months like March and April maintain similar patterns with 11 to 13 days of rainfall. Interestingly, September features a decline in rainy days, averaging just 9, although it still retains a substantial 113 mm (4.4 in). The consistent distribution of rainfall throughout the year supports Pennsylvania's lush landscapes, though seasonal variations highlight the distinct transitions between wetter and drier periods.
In Pennsylvania, sunshine duration exhibits a clear seasonal trend, with hours of sunlight steadily increasing as the winter months give way to spring and summer. January experiences the least sunshine, with a mere 122 hours, while February sees a slight improvement to 156 hours. As March arrives, a significant rise to 231 hours signals the onset of spring, culminating in the month of May, which reaches an impressive 266 hours of sunshine. This upward trajectory continues into the summer, reaching its peak in July with 338 hours, providing ample daylight for outdoor activities and vibrant seasonal growth.
As summer transitions into fall, the number of sunshine hours begins to taper off, yet September retains a healthy 272 hours, which is still above average for the year. October marks a further decline to 219 hours, with November dipping to 191 hours as days grow shorter. By December, sunlight decreases to 155 hours, highlighting the enduring influence of winter's early onset. This cyclical pattern in sunshine duration not only enhances Pennsylvania's seasonal beauty but also influences various ecosystems, agricultural practices, and residents' outdoor lifestyle throughout the year.
The UV Index (UVI) in Pennsylvania follows a distinct pattern that correlates with the changing seasons, indicating the varying levels of ultraviolet radiation throughout the year. During the winter months, January and December exhibit lower UVI values, measuring 5 and 4, respectively. February marks an increase to 7 as the sun's intensity begins to rise, while March sees a notable jump to 9, signaling the approach of spring and increased sun exposure.
As Pennsylvanians transition into summer, the UVI peaks, maintaining a consistent level of 11 from April through August. This period emphasizes the importance of sun protection, as heightened UV radiation can pose health risks. By September, the UVI begins to decline to 10, and continues to decrease through the fall, arriving at 8 in October and 6 in November. These seasonal variations in the UVI not only reflect the changing climatic conditions but also serve as a timely reminder for residents to be mindful of sun safety throughout the year.
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In Pennsylvania, daylight duration demonstrates a clear seasonal rhythm, reflecting the annual cycle of light and darkness. Starting in January, residents experience only about 9 hours of daylight, which gradually increases to 10 hours in February and 11 hours in March. As spring transitions into summer, daylight hours expand significantly, reaching a peak of 15 hours in June, allowing ample time for outdoor activities and enjoying nature during the warmer months.
Following the summer solstice, daylight hours begin to decrease, transitioning back to 14 hours in July and gradually tapering off throughout the fall. By September, the duration drops to 12 hours, and further declines to 11 hours in October. As winter approaches, the cycle completes with shorter days returning to 9 hours in both November and December. This natural fluctuation in daylight hours not only influences daily routines and recreational activities but also plays a vital role in the ecological processes within Pennsylvania's diverse landscapes.
Bear Rocks, United States, experiences a diverse climate with significant temperature fluctuations throughout the year. Winters can be harsh, with January temperatures ranging from -27°C (-16°F) to 21°C (70°F), while summers are warmer, exemplified by July temperatures between 12°C (54°F) to 34°C (94°F). Precipitation peaks during the spring and summer months, with June receiving the highest at 162 mm (6.4 in), and remains moderate during the rest of the year. Sunshine varies significantly, with July enjoying the most at 337 hours, contrasting with the shorter days of January that only see 109 hours. For more details, check the Bear Rocks climate.
Bethlehem, United States, experiences a diverse climate with distinct seasonal variations. Winters are cold, with average temperatures in January and February around 0°C (32°F) and 1°C (35°F), respectively, and minimal sunshine, while summers heat up to an average of 25°C (76°F) in July, accompanied by the most sunshine at 334 hours. Precipitation is fairly consistent throughout the year, peaking in May and August with 139 mm (5.5 in) and 140 mm (5.5 in), respectively. The transitional months, like April and October, offer milder temperatures averaging around 10°C (51°F) and 14°C (58°F). For more detailed information on the climate, visit the Bethlehem climate page.
The climate in Delaware Water Gap, United States, is characterized by a diverse range of temperatures, with cold winters and warm summers. During winter months, temperatures can drop to as low as -21°C (-6°F) in February, while summer temperatures may reach up to 35°C (95°F) in July. The area receives moderate precipitation throughout the year, with August being the wettest month at 146 mm (5.7 in) of rain. Sunshine hours peak in the summer, with July receiving 332 hours of sunlight, contrasting starkly with winter months like January, which has 133 hours. For further details, visit the Delaware Water Gap climate.
Gettysburg experiences a varied climate with cold winters and warm summers. January temperatures can drop to a chilly -17°C (2°F), and the month receives around 62 mm (2.4 in) of precipitation. Summers are warmer, with July and August having average highs of up to 36°C (97°F) and receiving up to 134 mm (5.3 in) of rainfall. The area enjoys a fair amount of sunshine annually, peaking in July with around 350 hours of sun. For more details, you can visit the Gettysburg climate.
Hershey, United States, experiences a diverse climate characterized by cold winters and hot summers. Winter months, from December to February, have average temperatures ranging from 1°C to 3°C (34°F to 38°F), with lows plummeting to -17°C (2°F). Summers, particularly in July, see averages around 25°C (78°F), reaching highs of up to 37°C (99°F). Annual precipitation peaks in July at 136 mm (5.4 in), while sunshine duration is longest in summer, with July receiving 344 hours. For a detailed overview, visit the Hershey climate page.
Intercourse, United States, experiences a diverse climate with temperatures ranging from cold winters to warm summers. In winter months such as January, temperatures can drop to -19°C (-3°F) with average monthly precipitation around 65 mm (2.6 in). Summers are warm, with average July temperatures reaching 25°C (78°F) and monthly rainfall peaking at 156 mm (6.1 in). Sunshine varies throughout the year, from 137 hours in January to a peak of 347 hours in July. To learn more about the climate in Intercourse, visit Intercourse climate.
Jim Thorpe, Pennsylvania, experiences a diverse climate with distinct seasonal changes. Winters are cold, with temperatures ranging from -22°C to 16°C, while summers are warm, peaking at 34°C in July. The region receives moderate to heavy precipitation throughout the year, with July and August being the wettest months, at 158 mm and 161 mm respectively. Sunshine varies widely, with the sunniest month being July, providing 335 hours of sunlight. For more detailed information, visit the Jim Thorpe climate page.
Lancaster, Pennsylvania, experiences a diverse climate with temperatures ranging from cold winters to warm and humid summers. In winter months such as January and February, temperatures can drop to a frigid -16°C (3°F), whereas summer months like July see averages soaring to 26°C (78°F) with highs reaching 36°C (97°F). Lancaster receives a moderate amount of precipitation throughout the year, peaking in the summer months with July and August accumulating 135 mm (5.3 in) and 138 mm (5.4 in) respectively. The city also enjoys considerable sunshine, particularly in June and July, with up to 347 hours of sun, contributing to its lush landscapes. For more detailed information, you can view the Lancaster climate.
Milford, United States, experiences a diverse climate characterized by cold winters and warm summers. During winter months, temperatures can plummet to as low as -23°C (-9°F), with average highs reaching up to 24°C (75°F) in February. Summers offer more warmth, with average temperatures peaking in July at 23°C (75°F) and maximums reaching up to 35°C (95°F). Precipitation is highest in October, with 144 mm (5.7 in), while May to August sees substantial rainfall averaging over 120 mm (4.7 in) per month. The area enjoys ample sunshine, notably June and July, with over 300 hours of sunshine each month. For more detailed information, visit Milford climate.
Nemacolin, United States, experiences a diverse climate with temperatures that can vary dramatically throughout the year. Winters are cold, with January showing average lows of around -23°C (-10°F) and highs reaching up to 22°C (72°F), and moderate precipitation averaging 87 mm (3.4 in) per month. The summers are warm, particularly in July and August, where temperatures reach highs of 34°C (94°F) with precipitation peaking at 172 mm (6.8 in) in June. The area enjoys substantial sunshine from spring to early fall, with July boasting up to 329 hours of sunlight. For more detailed climate information, visit Nemacolin climate.
The climate in New Hope, United States, is characterized by cold winters and warm summers, with temperature lows reaching -17°C (2°F) in January and highs soaring to 37°C (98°F) in July. The area experiences considerable precipitation throughout the year, peaking in July and August with around 145 mm (5.7 in) each month, while May sees the highest levels at 138 mm (5.4 in). Sunshine duration varies, with the lowest in January at 142 hours and the highest in July at 345 hours. For more detailed information, you can visit the New Hope climate page.
Philadelphia experiences a diverse climate with chilly winters and hot summers. In January, temperatures range from a brisk -17°C (1°F) to 20°C (68°F), while July sees warmer days with temperatures from 14°C (58°F) to 37°C (99°F). Precipitation is fairly consistent throughout the year, averaging between 63 mm (2.5 in) in January and 134 mm (5.3 in) in August. The city enjoys increasing sunshine from winter to summer, with January seeing 144 hours of sunshine, peaking in July at 346 hours. For more detailed climate information, visit the Philadelphia climate page.
Pittsburgh experiences a climate with four distinct seasons, characterized by cold winters and warm summers. Winter temperatures can plunge to lows of -22°C (-8°F) in January, while summer can reach highs of 35°C (96°F), particularly in July. Precipitation is relatively evenly distributed throughout the year, with the wettest months being May and June, averaging around 150-155 mm (5.9-6.1 inches). Sunshine varies greatly, from a low of 104 hours in January to a peak of 332 hours in July, reflecting the seasonal daylight trends. For more details on Pittsburgh climate.
Punxsutawney experiences a varied climate with cold winters and warm summers. Winter months, from December to February, see minimum temperatures dipping to -24°C (-12°F) and a moderate range of precipitation peaking in February at 123 mm (4.9 in). As spring arrives, warming to an average of 9°C (48°F) by April, rainfall increases to about 134 mm (5.3 in), and sunshine reaches 234 hours. The summer months bring average highs of 22°C (72°F) in July and abundant sunshine, with a peak of 326 hours in July, accompanied by moderate rainfall of about 129 mm (5.1 in). As autumn approaches, temperature and sunshine decrease, with September averaging 18°C (65°F) and 274 sunshine hours, paired with diminishing rainfall. For more detailed information, visit Punxsutawney climate.
Strasburg, United States, experiences distinct seasonal variations with cold winters and warm summers. January is the coldest month, with temperatures ranging from -15°C (4°F) to 19°C (66°F), while July is the warmest, with a range of 14°C (58°F) to 36°C (97°F). Precipitation is fairly distributed throughout the year, with the wettest months being July and August, receiving 135 mm (5.3 in) and 138 mm (5.4 in) respectively. Sunshine hours peak in summer, notably in July with 347 hours, contrasting with the shorter, gloomier days of winter. More information can be found on Strasburg climate.
In conclusion, Pennsylvania's climate exhibits dynamic and seasonal variations that significantly impact the state's environmental and social fabric. From temperature fluctuations ranging from frigid winter lows to sultry summer highs, to the diverse precipitation patterns that feed its lush landscapes, the state's weather forms an intricate tapestry of natural phenomena. Additionally, the trends in sunshine duration and the UV Index underscore the importance of sun safety, particularly during the peak summer months. Understanding these climactic and seasonal trends not only enhances residents' appreciation for their environment but also equips them with the knowledge to adapt their daily lives, ensuring health and well-being throughout the changing seasons.