Allentown, Pennsylvania, experiences distinct seasonal changes throughout the year. Summers are warm, humid, and often wet, while winters are cold and snowy.
The average temperature fluctuates dramatically, ranging from 20°F in the winter to 86°F in the summer.
Rainfall in Allentown averages 47 inches annually, with the highest precipitation occurring during the summer months.
Snowfall averages 29 inches each year, providing plenty of opportunities for winter activities.
During spring and fall, the weather is relatively mild and partly cloudy. These transitional seasons offer a pleasant balance, making these months popular for outdoor activities and events in Allentown.
For more detailed monthly weather data, you can check the climate information on Allentown Climate – BestPlaces.
Average Temperature in Allentown, Pennsylvania
The climate in Allentown, Pennsylvania, varies significantly throughout the year.
During the summer months, temperatures can reach as high as 86°F and occasionally go above 93°F. These warm months are often accompanied by humid conditions.
In contrast, winters in Allentown can be very cold.
Temperatures typically range from 23°F to 9°F, and sometimes even drop lower. January and February are the coldest months, with February average temperatures around 29.8°F.
A table summarizing the average high and low temperatures by month can help visualize the yearly temperature changes.
| Month | Avg High (°F) | Avg Low (°F) |
|---|---|---|
| January | 37 | 23 |
| February | 40 | 24 |
| March | 50 | 32 |
| April | 63 | 42 |
| May | 73 | 52 |
| June | 81 | 61 |
| July | 86 | 66 |
| August | 84 | 64 |
| September | 77 | 56 |
| October | 65 | 45 |
| November | 53 | 36 |
| December | 41 | 27 |
Warm months like July have the highest temperatures, and the average summer temperatures can be pleasant for outdoor activities.
Temperature changes are less pronounced during the spring and fall, providing mild and comfortable weather.
Average Precipitation in Allentown, Pennsylvania
Allentown, Pennsylvania experiences a variety of precipitation patterns throughout the year, including both rainfall and snowfall. The city faces different amounts of precipitation depending on the season.
Average Rainfall in Allentown, Pennsylvania
Rainfall in Allentown varies significantly by season.
The city experiences a long wetter season from April 1 to August 24, with a greater than 30% chance of experiencing rainy days. The wettest month is June, averaging about 11.3 days with at least 0.04 inches of rain.
Annual rainfall amounts reach approximately 45.35 inches.
Rainfall is crucial for maintaining the green landscapes and supporting local agriculture. The summer months bring the most rain, which is essential for plant growth and sustaining water reservoirs.
Winter months, though colder, also receive rainfall. However, snowfall becomes more significant in these months, impacting the total precipitation.
Average Snow in Allentown, Pennsylvania
Winter in Allentown brings considerable snowfall, especially in January and February.
January is typically the coldest month with average temperatures around 29.4°F. Snowfall is frequent, contributing to above-normal precipitation levels during winter.
The presence of snow is common from late November through March. February often has significant snowfall, making it one of the snowiest months.
Snow accumulation can impact daily life, from transportation to local events.
The combination of both rainfall and snowfall ensures that Allentown has a dynamic and varied annual precipitation profile. This variety influences local climate patterns and affects the region’s environment and lifestyle.
Average Sun in Allentown, Pennsylvania
Allentown experiences varying amounts of sunlight throughout the year, with notable differences between the seasons. The data provides insight into important charts and averages that characterize the city’s solar energy.
Average Daily Shortwave Solar Energy in Allentown, Pennsylvania
From November to February, the daily incident shortwave solar energy is quite low. In December, it averages about 1.8 kWh per square meter. This period is generally the darkest of the year.
In contrast, June sees the most sunlight, with an average of 6.8 kWh per square meter. Summers are therefore relatively bright and sunny.
The solar energy received in spring and autumn falls between these extremes, reflecting the moderate transition in weather conditions.
Average Humidity in Allentown, Pennsylvania
Allentown, Pennsylvania experiences varying levels of humidity throughout the year.
Monthly Average Humidity:
- January: 70%
- February: 66%
- March: 62%
- April: 61%
- May: 66%
- June: 68%
- July: 70%
- August: 72%
- September: 74%
- October: 72%
- November: 70%
- December: 71%
The highest humidity occurs in September with an average of 74% while the lowest is in April at about 61%.
Typical annual relative humidity levels in Allentown hover around 66%.
This city has a noticeable rise in humidity during late summer months, making it feel more sticky and warm.
The average humidity percentage range demonstrates the climate’s shift from relatively comfortable conditions in spring to more humid periods in late summer and early autumn.
Average Wind in Allentown, Pennsylvania
The average wind speed in Allentown is quite modest. Throughout the year, the wind maintains a steady pace, contributing to the city’s climate but not typically causing significant disruptions.
In general, the average wind speed is around 10 kph (6 mph). This level of wind is considered quite comfortable for most outdoor activities.
During certain periods, particularly in summer, the average daily wind speed can be slightly higher. Specifically, it’s often around 18 mph.
Wind patterns in Allentown can vary by month.
For those interested in more detailed information, wind patterns may show seasonal changes.
Wind Overview:
- Annual Average Speed: 10 kph (6 mph)
- Summer Peaks: up to 18 mph
This level of wind aids in keeping the temperature pleasant during the hotter months while ensuring that winter winds are not excessively harsh.
Average Air Quality in Allentown, Pennsylvania
Allentown’s air quality varies throughout the year due to factors like weather and local emissions.
The Air Quality Index (AQI) in Allentown is generally rated as “Good,” meaning that air pollution poses little or no risk.
However, some areas experience more poor air quality days.
In South Allentown, the number of days with an AQI greater than 100 is moderate. This indicates a higher level of pollutants on certain days, which can affect sensitive groups.
A report on pollution showed that the Allentown-Bethlehem-Easton metro area ranks 79th-worst in the nation for ozone pollution.
These rankings are based on the worst days recorded, impacting residents with respiratory conditions.
A comparative look shows that Allentown has better air quality than 82 other cities in Pennsylvania. This is notable given the variance in city sizes and industrial activity statewide.
Temperature and weather patterns also influence air quality. With average temperatures ranging from 23°F in winter to 86°F in summer, the city sees fluctuations in pollutant levels based on these seasonal changes.
Monitoring air quality trends helps residents make informed decisions about outdoor activities, especially during days with higher pollution levels. This awareness is vital for maintaining public health and well-being.
Topography of Allentown, Pennsylvania
Allentown, located in Eastern Pennsylvania, sits within the Lehigh Valley. The area is known for its varied terrain and moderate elevation.
Elevation and Terrain:
The average elevation of Allentown is about 509 feet above sea level.
This moderate elevation provides a mix of rolling hills and flat areas, making the landscape diverse and scenic.
Lehigh Valley International Airport:
Lehigh Valley International Airport, situated to the northeast of Allentown, serves as a key transportation hub for the region. The airport’s elevation is slightly lower than the city’s average, contributing to its accessibility and wide runways.
Nearby Features:
- Fogelsville: This area in Upper Macungie Township has a similar elevation and shares the valley’s characteristic topography.
- Lehigh River: The river runs nearby, creating a natural boundary and contributing to the valley’s varied landscape.
Accessibility:
The terrain around Allentown is largely accessible, with major highways running through the valley. These routes facilitate travel and connect the city to surrounding areas.
Extreme Weather Events that Occur in Allentown, Pennsylvania
Allentown, Pennsylvania experiences a variety of extreme weather events throughout the year.
Flooding is a significant concern. Heavy rainfall can cause the rivers to overflow, leading to residential and commercial areas being submerged.
The city sees an average precipitation of about 1,152 mm per year, which can contribute to these flooding events.
During summer, above-normal temperatures can lead to heatwaves. Average highs in July reach the mid-80s Fahrenheit, sometimes spiking even higher.
Prolonged heat can pose health risks, especially to the elderly and young children.
Winter brings severe winter precipitation. Snowstorms and freezing rain are common, causing hazardous travel conditions and potential power outages.
January is the coldest month, with temperatures often falling below freezing.
Climate change is impacting the frequency and intensity of these events. Rising temperatures contribute to more extreme weather patterns.
Increased precipitation and more frequent heatwaves are expected as a result.
While Allentown is inland, coastal flooding from hurricanes can still affect the area. Heavy rains and winds from such storms can cause similar flood conditions as those from local precipitation events.
Best Time of the Year to Visit Allentown, Pennsylvania
Deciding the best time to visit Allentown depends on what kind of activities you enjoy. Each season offers something unique, from pleasant weather in spring and autumn to hot summers and snowy winters.
What is Allentown, Pennsylvania Like in Spring
Spring in Allentown starts in March and is a beautiful time of year with temperatures warming from the 40s in March to the 60s by May. Trees and flowers bloom, making parks and gardens vibrant and colorful.
Rainfall is common in spring, so packing an umbrella is a good idea.
Outdoor activities like hiking and visiting local parks are popular during this season. It is also a great time to explore the city’s festivals and local markets.
What is Allentown, Pennsylvania Like in Summer
Summer in Allentown runs from June through August. The warmest month, July, sees average highs of around 88°F.
The days are long and sunny, perfect for outdoor activities such as swimming, fishing, and picnics.
Though it can be humid, many visitors and locals head to Dorney Park & Wildwater Kingdom, a popular amusement park in the area.
It’s advisable to stay hydrated and use sunscreen to protect against the sun’s strong rays.
What is Allentown, Pennsylvania Like in Fall
Fall in Allentown is from September to November. This season is known for its crisp air and stunning fall foliage.
Temperatures range from the 70s in early fall to the 50s by November.
Many people enjoy visiting local farms for apple picking and pumpkin patches. The Lehigh Valley Wine Trail is also particularly beautiful and enjoyable during this time of year. Layered clothing is recommended as temperatures can vary.
What is Allentown, Pennsylvania Like in Winter
Winter in Allentown starts in December and lasts until February.
Average temperatures during the winter season can range from the mid-30s to the low 20s. Snow is common, with an average of 29 inches per year.
This is a great time to enjoy winter sports like skiing and snowboarding at nearby resorts.
Holiday events and decorations bring a festive atmosphere to the city.
Warm clothing and boots are essential to stay comfortable in the cold.
Spring, summer, fall, or winter, Allentown has something to offer every visitor.