April weather forecast and climate
St. Louis, MO

A beautiful twilight view of the Gateway Arch in St. Louis, Missouri, with a distant view of the city buildings mirrored in the waterfront
A beautiful twilight view of the Gateway Arch in St. Louis, Missouri, with a distant view of the city buildings mirrored in the waterfront
April is a comfortable spring month in St. Louis, with average temperature varying between 67.5°F (19.7°C) and 47.1°F (8.4°C).

Temperature

In St. Louis, Missouri, the average high-temperature rises, from a mild 55.9°F (13.3°C) in March, to an enjoyable 67.5°F (19.7°C). In St. Louis, Missouri, the average low-temperature is 47.1°F (8.4°C).

Humidity

With an average relative humidity of 63.5%, April is the least humid month in St. Louis.

Rainfall

In St. Louis, during April, the rain falls for 11.3 days and regularly aggregates up to 3.69" (93.7mm) of precipitation. Throughout the year, in St. Louis, Missouri, there are 112.6 rainfall days, and 40.96" (1040.3mm) of precipitation is accumulated.

Snowfall

Months with snowfall in St. Louis, Missouri, are January through April, November and December. April is the last month it regularly snows in St. Louis, Missouri. During 0.3 snowfall days, in April, St. Louis aggregates 0.4" (10.2mm) of snow. Throughout the year, in St. Louis, there are 14.5 snowfall days, and 17.7" (449.6mm) of snow is accumulated.

Daylight

The average length of the day in St. Louis is 13.3h.

Sunshine

The average sunshine in April in St. Louis, Missouri, is 7.5h.

UV index

In April, the average daily maximum UV index in St. Louis is 7. A UV Index of 6 to 7 symbolizes a high health vulnerability from the exposure to the Sun's UV rays for ordinary individuals.
Note: The daily maximum UV index of 7 in April interpret into the following advice:
Take precautions and utilize sun safety practices. Protection against the skin and eye damage is required. 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. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.

What is the temperature in April in St. Louis?

In St. Louis, Missouri, in April, the average high-temperature is 67.5°F (19.7°C), and the average low-temperature is 47.1°F (8.4°C).

What is the least humid month in St. Louis?

The least humid month in St. Louis, Missouri, is April, with an average relative humidity of 63.5%.

What is the average humidity in April in St. Louis?

In St. Louis, Missouri, the average relative humidity in April is 63.5%.

How many days does it rain in April in St. Louis?

In April, the rain falls for 11.3 days. Throughout April, 3.69" (93.7mm) of precipitation is accumulated.

What is the last month it snows in St. Louis?

April is the last month it regularly snows. During 0.3 snowfall days, in April, St. Louis aggregates 0.4" (10.2mm) of snow.

What is the average length of the day in April in St. Louis?

In St. Louis, the average length of the day in April is 13.3h.

How many hours of sunshine does St. Louis have in April?

In April, the average sunshine in St. Louis is 7.5h.

How high is the UV index in April in St. Louis?

The average daily maximum UV index in April in St. Louis is 7. A UV Index of 6 to 7 symbolizes a high health threat from unprotected exposure to the UV radiation.
Average temperature in April - St. Louis, MO
  • Average high temperature in April: 19.7°C

The warmest month (with the highest average high temperature) is July (31.7°C).
The month with the lowest average high temperature is January (4.4°C).

  • Average low temperature in April: 8.4°C

The month with the highest average low temperature is July (21.7°C).
The coldest month (with the lowest average low temperature) is January (-4.6°C).

Average humidity in April - St. Louis, MO
  • Average humidity in April: 63.5%

The month with the highest relative humidity is December (75.8%).
The month with the lowest relative humidity is April (63.5%).

Average rainfall in April - St. Louis, MO
  • Average rainfall in April: 93.7mm

The wettest month (with the highest rainfall) is May (119.9mm).
The driest month (with the least rainfall) is February (56.9mm).

Average rainfall days in April - St. Louis, MO
  • Average rainfall days in April: 11.3 days

The month with the highest number of rainy days is May (11.9 days).
The month with the least rainy days is September (7.4 days).

Average snowfall in April - St. Louis, MO
  • Average snowfall in April: 10.2mm

The month with the highest snowfall is January (142.2mm).
Months with the least snowfall are May, June, July, August, September and October (0mm).

Average snowfall days in April - St. Louis, MO
  • Average snowfall days in April: 0.3 days

The month with the highest number of snowfall days is January (4.7 days).
Months with the least snowfall days are May, June, July, August, September and October (0 days).

Average daylight in April / Average sunshine in April - St. Louis, MO
  • Average daylight in April: 13.3h

The month with the longest days is June (Average daylight: 14.8h).
The month with the shortest days is December (Average daylight: 9.5h).

  • Average sunshine in April: 7.5h

The month with the most sunshine is July (Average sunshine: 10h).
The month with the least sunshine is December (Average sunshine: 4.2h).

Average UV index in April - St. Louis, MO
  • Average UV index in April: 7

Months with the highest UV index are June, July and August (UV index 9).
Months with the lowest UV index are January and December (UV index 2).