St. Louis
Missouri, USA
Long-term weather forecast
Long-term weather forecast

May 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
Mayo, the last month of the spring, in St. Louis, is a moderately hot month, with average temperature fluctuating between 76.3°F (24.6°C) and 57.2°F (14°C).

Temperature

In Mayo, the average high-temperature in St. Louis slightly increases, from a comfortable 67.5°F (19.7°C) in Abril, to a moderately hot 76.3°F (24.6°C). The average low-temperature, in St. Louis, is 57.2°F (14°C).

Humidity

In Mayo, the average relative humidity in St. Louis is 66.5%.

Rainfall

Mayo is the month with the most rainfall in St. Louis. Rain falls for 11.9 days and accumulates 4.72" (119.9mm) of precipitation.

Snowfall

Mayo through Octubre are months without snowfall in St. Louis, Missouri.

Daylight

In St. Louis, the average length of the day in Mayo is 14.3h.

Sunshine

The average sunshine in Mayo in St. Louis is 8.6h.

UV index

In St. Louis, the average daily maximum UV index in Mayo is 8. A UV Index of 8 to 10 symbolizes a very high health risk from the exposure to the Sun's UV radiation for the average person.
Note: In Mayo, the average maximum UV index of 8 translate into the following recommendations:
Take special precautions, as unprotected skin can be damaged and can burn quickly. 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. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes.

What is the temperature in Mayo in St. Louis?

In St. Louis, Missouri, in Mayo, the average high-temperature is 76.3°F (24.6°C), and the average low-temperature is 57.2°F (14°C).

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

The average relative humidity in Mayo in St. Louis is 66.5%.

How much does it rain in St. Louis in Mayo?

In St. Louis, in Mayo, it is raining for 11.9 days, with typically 4.72" (119.9mm) of accumulated precipitation.

What is the wettest month in St. Louis?

Mayo is the month with the most rainfall in St. Louis, Missouri. Rain falls for 11.9 days and accumulates 4.72" (119.9mm) of precipitation.

Does it snow in St. Louis in Mayo?

In Mayo, in St. Louis, Missouri, it doesn't snow. Abril is the latest month when it typically snows.

When it does not snow in St. Louis?

In St. Louis, Missouri, snow does not fall in Mayo through Octubre.

How many hours of daylight does St. Louis have in Mayo?

The average length of the day in Mayo in St. Louis is 14.3h.

How long on average sun shines in Mayo in St. Louis?

In St. Louis, the average sunshine in Mayo is 8.6h.

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

In Mayo, the average daily maximum UV index is 8. A UV Index value of 8 to 10 symbolizes a very high health risk from unprotected exposure to the UV radiation.
Average temperature in May - St. Louis, MO
  • Average high temperature in May: 76.3°F

The warmest month (with the highest average high temperature) is July (89.1°F).
The month with the lowest average high temperature is January (39.9°F).

  • Average low temperature in May: 57.2°F

The month with the highest average low temperature is July (71°F).
The coldest month (with the lowest average low temperature) is January (23.7°F).

Average humidity in May - St. Louis, MO
  • Average humidity in May: 66.5%

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 May - St. Louis, MO
  • Average rainfall in May: 4.7"

The wettest month (with the highest rainfall) is May (4.7").
The driest month (with the lowest rainfall) is February (2.2").

Average rainfall days in May - St. Louis, MO
  • Average rainfall days in May: 11.9 days

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

Average snowfall in May - St. Louis, MO
  • Average snowfall in May: 0"

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

Average snowfall days in May - St. Louis, MO
  • Average snowfall days in May: 0 days

The month with the highest number of snowfall days is January (4.7 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 - St. Louis, MO
  • Average daylight in May: 14.3h

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

  • Average sunshine in May: 8.6h

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

Average UV index in May - St. Louis, MO
  • Average UV index in May: 8

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).