Allentown (PA) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Allentown.
Climate overview of Allentown
The climate in Allentown, Pennsylvania, United States of America, is marked by large temperature swings across the seasons, ranging from 30°C (86°F) in July to 3°C (37°F) in January.
The city has a wet climate, receiving around 1294 mm (51 in) of rain/snowfall per year. June is the wettest month.
Allentown Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Allentown — and find the best time to visit.
Monthly Temperature in Allentown
In Allentown, temperatures differ significantly between summer and winter months. On average, daytime temperatures range from a comfortable 30°C (86°F) in July to a chilly 3°C (37°F) in January.
Nighttime temperatures range from 19°C (66°F) in July to -6°C (21°F) in January.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Allentown
Allentown experiences significant rain/snowfall throughout the year, averaging 1294 mm (51 in) of precipitation annually. The amount of precipitation varies moderately throughout the year. The wettest month, June, sees around 145 mm (5.7 in) of rainfall, perfect for those who enjoy a bit of rain now and then. The driest month, November, still receives a respectable 72 mm (2.8 in) of rainfall. For more details, please visit our Allentown Precipitation page.
The mean monthly precipitation over the year, including rain, hail, and snow
The average number of days each month with precipitation
Sunshine Hours in Allentown
Daily percentage of sunshine
Humidity in Allentown by Month
The relative humidity is high throughout the year in Allentown.
The city experiences its highest humidity in September, reaching 74%. In April, the humidity drops to its lowest level at 61%. What does this mean? Read our detailed page on humidity levels for further details.
Relative humidity over the year
Best Time to Visit Allentown
Frequently asked questions about the climate in Allentown
What is the best time to visit Allentown?
May, June, August and September typically offer the most optimal weather in Allentown. In contrast, January, February, March and December tend to have less optimal conditions.
What temperatures can I expect in Allentown?
Daytime highs range from 3°C (37°F) in January to 30°C (86°F) in July. Nighttime lows range from -6°C (21°F) to 19°C (66°F). Temperatures vary considerably through the year.
How much rain does Allentown get?
Annual rainfall is around 1294 mm (51 in). June is the wettest month with 145 mm (5.7 in), while November is the driest with 72 mm (2.8 in).
Allentown 3-Day Forecast
Allentown (PA) 3-Day Forecast
Allentown on the map
Allentown is highlighted — select any city to see its climate.
Popular this month
Where to go in July — average daytime high across popular destinations.
Bucket list
Need travel inspiration? Check out our bucket list articles and be inspired.
Yosemite National Park is definitely worth a visit
Vast forests, blue lakes, towering sequoias, and majestic waterfalls hint at the beauty of Yosemite National Park—a true natural masterpiece.
The 10 most alternative cities in the United States
Discover the top 10 fun and alternative U.S. cities rich in art, culture, and adventure. From Portland's hippy charm to Sedona's stunning landscapes.
Sedona: Explore Majestic Red Rock Landscapes
A picturesque artists' town surrounded by red rocks and known for its spirituality, vortex energy, and stunning hikes like Cathedral Rock.
10 most idyllic villages to visit in the United States
Discover 10 idyllic villages in the USA, from California to Vermont. Explore their unique charm, rich history, stunning nature, and vibrant arts scenes.