Allentown
Pennsylvania, USA
Long-term weather forecast
Long-term weather forecast

May weather forecast and climate
Allentown, PA

An aerial view of the vast city of Allentown in Pennsylvania, on a hot, sunny day, with the partly cloudy sky and a far view of a clear horizon line
An aerial view of the vast city of Allentown in Pennsylvania, on a hot, sunny day, with the partly cloudy sky and a far view of a clear horizon line
The last month of the spring, May, is a pleasant month in Allentown, Pennsylvania, with average temperature ranging between max 71.4°F (21.9°C) and min 48.4°F (9.1°C).

Temperature

In May, the average high-temperature rises, from a comfortable 61.3°F (16.3°C) in April, to an agreeable 71.4°F (21.9°C). In May, the average low-temperature is 48.4°F (9.1°C).

Humidity

In Allentown, the average relative humidity in May is 65.6%.

Rainfall

In Allentown, during May, the rain falls for 12.1 days and regularly aggregates up to 4.1" (105.2mm) of precipitation. Throughout the year, there are 126.8 rainfall days, and 45.4" (1151.9mm) of precipitation is accumulated.

Snowfall

May through October are months without snowfall.

Daylight

In May, the average length of the day in Allentown is 14.5h.

Sunshine

In May, the average sunshine in Allentown is 8h.

UV index

The average daily maximum UV index in Allentown is 7. A UV Index of 6 to 7 symbolizes a high health hazard from unsafe exposure to the UV radiation for the average person.
Note: The daily maximum UV index of 7 interpret into the following advice:
Take precautions against overexposure. Protection against sun damage is needed. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun protection. A wide-brim hat offers excellent sun protection for eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Tightly woven, loose-fitting clothes provide additional protection from the Sun.

What is the temperature in May in Allentown?

In May, in Allentown, the average high-temperature is 71.4°F (21.9°C), and the average low-temperature is 48.4°F (9.1°C).

What is the average humidity in May in Allentown?

The average relative humidity in May in Allentown is 65.6%.

How much does it rain in Allentown in May?

In Allentown, in May, during 12.1 rainfall days, 4.1" (105.2mm) of precipitation is typically accumulated.

Does it snow in Allentown in May?

In May, in Allentown, it doesn't snow. April is the latest month when it typically snows.

When it does not snow in Allentown?

May through October are months without snowfall in Allentown, Pennsylvania.

What is the average length of the day in May in Allentown?

In Allentown, the average length of the day in May is 14.5h.

How many hours of sunshine does Allentown have in May?

In May, the average sunshine is 8h.

How high is the UV index in May in Allentown?

The average daily maximum UV index in May in Allentown, Pennsylvania, is 7. A UV Index value of 6 to 7 symbolizes a high health vulnerability from unsafe exposure to the Sun's UV rays.
Average temperature in May - Allentown, PA
  • Average high temperature in May: 71.5°F

The warmest month (with the highest average high temperature) is July (84.2°F).
The month with the lowest average high temperature is January (36°F).

  • Average low temperature in May: 48.3°F

The month with the highest average low temperature is July (62.7°F).
The coldest month (with the lowest average low temperature) is January (19.5°F).

Average humidity in May - Allentown, PA
  • Average humidity in May: 65.6%

The month with the highest relative humidity is September (74%).
The month with the lowest relative humidity is April (60.9%).

Average rainfall in May - Allentown, PA
  • Average rainfall in May: 4.1"

The wettest month (with the highest rainfall) is July (5").
The driest month (with the lowest rainfall) is February (2.7").

Average rainfall days in May - Allentown, PA
  • Average rainfall days in May: 12.1 days

Months with the highest number of rainy days are April and May (12.1 days).
Months with the lowest number of rainy days are September and October (9.1 days).

Average snowfall in May - Allentown, PA
  • Average snowfall in May: 0"

The month with the highest snowfall is February (11.1").
Months with the lowest snowfall are May, June, July, August, September and October (0").

Average snowfall days in May - Allentown, PA
  • Average snowfall days in May: 0 days

The month with the highest number of snowfall days is January (5.6 days).
Months with the lowest number of snowfall days are May, June, July, August, September and October (0 days).

Average daylight in May / Average sunshine in May - Allentown, PA
  • Average daylight in May: 14.5h

The month with the longest days is June (Average daylight: 15h).
The month with shortest days is December (Average daylight: 9.3h).

  • Average sunshine in May: 8h

Months with most sunshine are June and July (Average sunshine: 9h).
Months with least sunshine are November and December (Average sunshine: 4).

Average UV index in May - Allentown, PA
  • Average UV index in May: 7

Months with the highest UV index are June and July (UV index 9).
The month with the lowest UV index is December (UV index 1).