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Contents
- The climate of Allentown
- The best time to visit Allentown
- The worst time to visit Allentown
- Spring weather in Allentown
- Summer weather in Allentown
- Autumn weather in Allentown
- Winter weather in Allentown
- Weather in January
- Weather in February
- Weather in March
- Weather in April
- Weather in May
- Weather in June
- Weather in July
- Weather in August
- Weather in September
- Weather in October
- Weather in November
- Weather in December
- Frequently asked questions
- Average temperature
- Average pressure
- Average wind speed
- Average humidity
- Average rainfall
- Average rainfall days
- Average snowfall
- Average snowfall days
- Average daylight
- Average sunshine
- Average sunshine days
- Average UV index
- Average cloud cover
- Average visibility
An aerial panorama of the vast city of Allentown in Pennsylvania
The climate of Allentown
Pennsylvania's city, Allentown, basks in the idiosyncrasies of the Dfa or Humid Continental climate. The classification is a consequence of its geographical position and consistent weather patterns which manifest in no dry season and, instead, witness hot summers. Essentially, the weather varies significantly throughout the year, swaying between diverse extremes.
The annual temperature in Allentown fluctuates between 21.6°F (-5.8°C) and 83.8°F (28.8°C), with the former denoting the coldest month's low and the latter standing for the warmest month's peak. These temperatures, in conjunction with corresponding seasonal shifts, mark the return of climatic contrasts with the hottest months being July and August and the most frigid being January and February.
Rainfall averages between 1.61" (41mm) in the driest month and 3.03" (77mm) at the peak of the rainy season, suggesting precipitation is quite evenly spread and does not have a classically-defined dry month. On the other hand, snowfall is received from November to March, with January and February seeing the most significant snowfall, reaching up to 4.37" (111mm).
Another salient characteristic is the city's daylight range from 9.3 hours in December to 15 hours in June. This, coupled with the sunshine hours reaching from 4.4 hours in February to 10.4 hours in July, indicates a relatively bright summer weather, making outdoor activities quite enjoyable.
The annual temperature in Allentown fluctuates between 21.6°F (-5.8°C) and 83.8°F (28.8°C), with the former denoting the coldest month's low and the latter standing for the warmest month's peak. These temperatures, in conjunction with corresponding seasonal shifts, mark the return of climatic contrasts with the hottest months being July and August and the most frigid being January and February.
Rainfall averages between 1.61" (41mm) in the driest month and 3.03" (77mm) at the peak of the rainy season, suggesting precipitation is quite evenly spread and does not have a classically-defined dry month. On the other hand, snowfall is received from November to March, with January and February seeing the most significant snowfall, reaching up to 4.37" (111mm).
Another salient characteristic is the city's daylight range from 9.3 hours in December to 15 hours in June. This, coupled with the sunshine hours reaching from 4.4 hours in February to 10.4 hours in July, indicates a relatively bright summer weather, making outdoor activities quite enjoyable.
The best time to visit Allentown
Based upon weather parameters, May to September emerge as the most favorable months to visit Allentown. During this period, temperatures remain pleasant, fluctuating between 58.3°F (14.6°C) and 81°F (27.2°C), making it ideal for outdoor activities. Moreover, sunshine hours escalate up to 10.4 hours per day from June to July, adding a welcoming and warm hue to the days.
The worst time to visit Allentown
The months of January and February, characterized by the lowest temperatures between 21.6°F (-5.8°C) and 37.8°F (3.2°C), and heightened snowfall, may pose challenges for visitors. The short daylight hours, ranging down to 9.3 in December and limited sunshine, make it less inviting for tourists unfamiliar with such conditions.
Spring weather in Allentown
During spring, the temperatures in Allentown rise steadily from an average low of 30°F (-1.1°C) in March to a comfortable high around 69.4°F (20.8°C) in May. The average rainfall also shows an increasing trend from 2.17" (55mm) in March to 2.76" (70mm) in May, indicating that there could be occasional spring showers during this period.
Summer weather in Allentown
Summers in Allentown are warm, with average temperatures in July peaking to about 83.8°F (28.8°C). Evenings, however, are a respite, with temperatures going down to a comfortable 63.5°F (17.5°C). Relative humidity can be high, reaching up to 78%, but the days are bright with prolonged daylight hours reaching up to 15 hours and abundant sunshine extending to 10.4 hours.
Autumn weather in Allentown
Autumn in Allentown experiences a downward spiral in temperature, starting from around 74.3°F (23.5°C) in September to roughly 49.8°F (9.9°C) by November. The rainfall also shows gradual increment from 1.61" (41mm) in September to 2.17" (55mm) by November. However, daylight hours start declining, dropping to around 9.9 hours by November.
Winter weather in Allentown
With average lows of 21.6°F (-5.8°C) in January, winters in Allentown can be particularly chilly. Snowfall begins in November and peaks in February with up to 4.37" (111mm). However, despite the cold, the crisp winter air helps maintain good visibility, averaging around 6 miles in December to February.
Weather in January
In Allentown, January is known for its chilly temperatures. Notably, it has the lowest monthly temperatures, ranging from 21.6°F (-5.8°C) to 34°F (1.1°C). The cool embrace of winter can be felt with likely snowfall, totaling about 3.15" (80mm), and an average of 5 snowy days. Weather in January »
Weather in February
Even as winter continues in Allentown, February shows a slight increase in temperature as compared to January. Nonetheless, the cold season is still prevalent with more snow adding up to a significant amount of 3.11" (79mm) on approximately 6.6 days. Weather in February »
Weather in March
With March comes a significant warming trend in Allentown. The last of the winter snow, about 4.37" (111mm), is witnessed during this month. However, it does not push away rainfall, being one of the wettest months. Longer daylight, now up to 12 hours, signals the transition from winter to spring, as brightness begins to replace the gray wintry atmosphere. Weather in March »
Weather in April
April brings milder weather to Allentown, as winter well and truly gives way to spring. Temperatures range from 40.5°F (4.7°C) to 58.3°F (14.6°C). Warm sunshine bathes the landscape, illuminating the blooming spring flowers. April's weather differs greatly from that in March, with the longer daylight hours and considerable sun significantly improving visibility. Weather in April »
Weather in May
The month of May always seems to paint a beautiful picture of Allentown as flowering plants flourish in the warmer temperatures. Rainfall, however, reaches its peak at 2.76" (70mm) for the year, making May the wettest month. Daylight further increases and the city basks in over 14 hours of sunlight. Weather in May »
Weather in June
June sees the culmination of spring and the commencement of summer in Allentown. The city witnesses a dip in rain yet sunlight fills the most extended days of the year, making it an excellent period for outdoor endeavors. Pleasantly warm temperatures attract picnickers to parks and outdoor enthusiasts to local trails. Weather in June »
Weather in July
July in Allentown is typically recognized for its soaring temperatures. It is the hottest month, with temperature extremes at 63.5°F (17.5°C) to 83.8°F (28.8°C). Residents and tourists maximize their outdoor fun, with the weather supporting a variety of activities including boating, hiking, and nature walks. Weather in July »
Weather in August
August maintains the heat in Allentown despite being marginally cooler than July. Continued warm weather makes for splendid outings to the city's various natural and man-made attractions. The heat of summer is offset with a consistent breeze, making the high temperatures manageable. Weather in August »
Weather in September
September sees Allentown in transition from summer to fall, with temperatures starting to cool down steadily. Outdoor enthusiasts continue to enjoy activities in the lower temperatures and longer sunshine hours compared to August. Weather in September »
Weather in October
The weather in Allentown in October is a mix of crisp fall temperatures and cloudy skies. The almost 6.6mph (10.6km/h) breeze complements the dropping temperatures, making the leaf-peeping season an enjoyable time. Nature bursts into a riot of colors, highlighting the change in seasons. Weather in October »
Weather in November
November marks the tail end of fall, with a notable decrease in temperature in Allentown. It hints at the imminent arrival of winter, and even though the temperature takes a dip down, daylight hours shorten significantly. Overall, a cooler and cozier ambiance marks the city, prompting the beginning of indoor activities and festive preparations. Weather in November »
Weather in December
The last month of the year in Allentown ushers in the start of the chilly winter season. Conducive weather conditions prevail for snowfall, which measures up to 2.28" (58mm), marking the arrival of the winter wonderland. Although the cold might seem daunting, the festive mood fills the air, with snowy landscapes adding to the city's holiday charm. Weather in December »
Updated: Jun 19, 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
What are the coldest months?
The coldest period is January, when temperatures fluctuate between an average high of 34°F (1.1°C) and a low of 21.6°F (-5.8°C).
How much does it rain?
In Allentown, during the entire year, the rain falls for 145.1 days and collects up to 27.24" (692mm) of precipitation.
When does it snow?
Months with snowfall are January through May, October through December.
How many days does it snow in Allentown?
In Allentown, during the entire year, snow falls for 20.4 days and aggregates up to 13.82" (351mm) of snow.
What are the months with the lowest UV index?
January through March, November and December, with an average maximum UV index of 2, are months with the lowest UV index.
What is the most humid month?
The most humid month is February, with an average relative humidity of 82%.
What is the month with the least sunshine?
February has the least sunshine of the year, with an average of 4.4h of sunshine.
What is the snowiest month?
March is the month with the most snowfall in Allentown. Snow falls for 5.3 days and accumulates 4.37" (111mm) of snow.
When is Daylight Saving Time (DST)?
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.
What are the least humid months?
April and July, with an average relative humidity of 76%, are the least humid months in Allentown, Pennsylvania.
When it does not snow?
In Allentown, snow does not fall in June through September.
When are the longest days in Allentown?
The month with the longest days is June, with an average of 15h and 0min of daylight.
When is the highest UV index?
The months with the highest UV index are June and July, with an average maximum UV index of 6.
What is the warmest month in Allentown?
Allentown experiences its highest temperatures in July, with an average peak of 83.8°F (28.8°C) and a low of 63.5°F (17.5°C).
What is the wettest month?
July is the month with the most rainfall. Rain falls for 15.7 days and accumulates 3.03" (77mm) of precipitation.
What month has the most sunshine?
The month with the most sunshine is July, with an average of 10.4h of sunshine.
What is the driest month?
The month with the least rainfall is September, when the rain falls for 11.5 days and typically collects 1.61" (41mm) of precipitation.
What is the month with the shortest days?
With an average of 9h and 18min of daylight, December has the shortest days of the year in Allentown.
Average temperature
Allentown, PA
The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is January (34°F).
The month with the highest average low temperature is July (63.5°F).
The coldest month (with the lowest average low temperature) is January (21.6°F).
Average pressure
Allentown, PA
- Average pressure in January:
30.08"Hg - Average pressure in February:
30.05"Hg - Average pressure in March:
30.07"Hg - Average pressure in April:
29.99"Hg - Average pressure in May:
30.01"Hg - Average pressure in June:
29.94"Hg
- Average pressure in July:
29.96"Hg - Average pressure in August:
29.99"Hg - Average pressure in September:
30.06"Hg - Average pressure in October:
30.03"Hg - Average pressure in November:
30.12"Hg - Average pressure in December:
30.09"Hg
The month with the highest atmospheric pressure is November (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed
Allentown, PA
- Average wind speed in January:
7.9mph - Average wind speed in February:
7.8mph - Average wind speed in March:
8.1mph - Average wind speed in April:
7.9mph - Average wind speed in May:
6.2mph - Average wind speed in June:
5.8mph
- Average wind speed in July:
5.1mph - Average wind speed in August:
5mph - Average wind speed in September:
5.5mph - Average wind speed in October:
6.6mph - Average wind speed in November:
7mph - Average wind speed in December:
7.5mph
The windiest month (with the highest average wind speed) is March (8.1mph).
The calmest month (with the lowest average wind speed) is August (5mph).
Average humidity
Allentown, PA
The month with the highest relative humidity is February (82%).
The months with the lowest relative humidity are April and July (76%).
Average rainfall
Allentown, PA
- Average rainfall in January:
1.81" - Average rainfall in February:
1.73" - Average rainfall in March:
2.17" - Average rainfall in April:
2.44" - Average rainfall in May:
2.76" - Average rainfall in June:
2.32"
- Average rainfall in July:
3.03" - Average rainfall in August:
2.68" - Average rainfall in September:
1.61" - Average rainfall in October:
2.2" - Average rainfall in November:
2.17" - Average rainfall in December:
2.32"
The wettest month (with the highest rainfall) is July (3.03").
The driest month (with the least rainfall) is September (1.61").
Average rainfall days
Allentown, PA
- Average rainfall days in January:
6.7 days - Average rainfall days in February:
7.9 days - Average rainfall days in March:
11.7 days - Average rainfall days in April:
14.9 days - Average rainfall days in May:
16.9 days - Average rainfall days in June:
15.6 days
- Average rainfall days in July:
15.7 days - Average rainfall days in August:
14.8 days - Average rainfall days in September:
11.5 days - Average rainfall days in October:
11.9 days - Average rainfall days in November:
8.3 days - Average rainfall days in December:
9.2 days
The month with the highest number of rainy days is May (16.9 days).
The month with the least rainy days is January (6.7 days).
Average snowfall
Allentown, PA
- Average snowfall in January:
3.15" - Average snowfall in February:
3.11" - Average snowfall in March:
4.37" - Average snowfall in April:
0.2" - Average snowfall in May:
0.16" - Average snowfall in June:
0"
The month with the highest snowfall is March (4.37").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days
Allentown, PA
- Average snowfall days in January:
5 days - Average snowfall days in February:
6.6 days - Average snowfall days in March:
5.3 days - Average snowfall days in April:
0.3 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:
0.1 days - Average snowfall days in November:
0.5 days - Average snowfall days in December:
2.5 days
The month with the highest number of snowfall days is February (6.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Allentown, PA
- Average daylight in January:
9h and 4min - Average daylight in February:
10h and 4min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 2min - Average daylight in May:
14h and 3min - Average daylight in June:
15h and 0min
- Average daylight in July:
14h and 4min - Average daylight in August:
13h and 4min - Average daylight in September:
12h and 3min - Average daylight in October:
11h and 1min - Average daylight in November:
9h and 5min - Average daylight in December:
9h and 2min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in January:
4h and 4min - Average sunshine in February:
4h and 2min - Average sunshine in March:
6h and 1min - Average sunshine in April:
7h and 5min - Average sunshine in May:
8h and 1min - Average sunshine in June:
9h and 3min
- Average sunshine in July:
10h and 2min - Average sunshine in August:
9h and 5min - Average sunshine in September:
8h and 4min - Average sunshine in October:
5h and 2min - Average sunshine in November:
5h and 3min - Average sunshine in December:
4h and 4min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The month with the least sunshine is February (Average sunshine: 4h and 24min).
Average sunshine days
Allentown, PA
- Average sunshine days in January:
20.5 days - Average sunshine days in February:
14.8 days - Average sunshine days in March:
15.2 days - Average sunshine days in April:
13.4 days - Average sunshine days in May:
11.8 days - Average sunshine days in June:
12.4 days
- Average sunshine days in July:
13.4 days - Average sunshine days in August:
14 days - Average sunshine days in September:
16.5 days - Average sunshine days in October:
17 days - Average sunshine days in November:
20.2 days - Average sunshine days in December:
19.2 days
The month with the most sunshine days is January (20.5 days).
The month with the least sunshine days is May (11.8 days).
Average UV index
Allentown, PA
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover
Allentown, PA
The month with the most cloud cover is February (Cloud cover 52).
The month with the least cloud cover is July (Cloud cover 34).
Average visibility
Allentown, PA
The months with the highest visibility are April, July and November (6mi).
The months with the lowest visibility are January, February, March, May, June, August, September, October and December (5mi).
Allentown, Pennsylvania, USA
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