January weather forecast
St. Louis, MO

Today
Tomorrow
Long-term
YearJanuaryFMAMJJASOND
°Celsius°Fahrenheit
Share

Contents

A beautiful twilight over the Gateway Arch in St. Louis, Missouri
A beautiful twilight over the Gateway Arch in St. Louis, Missouri

Weather in January

January in St. Louis begins the year firmly within the grips of the winter season. Freezing conditions are predominant, with the lowest mean temperature of 23.7°F (-4.6°C). Winterscape often includes snowfall totaling 5.6" (142mm) across the city. The onset of the year also carries shorter days, with sunlight barely stretching beyond mid-afternoon. The pervading chill in the air set the stage for a period of relative tranquility in terms of rain.

Temperature

January is the coldest month in St. Louis, with an average high-temperature of 39.9°F (4.4°C) and an average low-temperature of 23.7°F (-4.6°C).

Humidity

The average relative humidity in January in St. Louis, Missouri, is 73%.

Rainfall

In St. Louis, in January, during 8.9 rainfall days, 2.4" (61mm) of precipitation is typically accumulated. Throughout the year, in St. Louis, Missouri, there are 112.6 rainfall days, and 40.94" (1040mm) of precipitation is accumulated.

Snowfall

Months with snowfall in St. Louis, Missouri, are January through April, November and December. The month with the most snowfall in St. Louis is January, when snow falls for 4.7 days and typically aggregates up to 5.59" (142mm) of snow.

Daylight

The average length of the day in January in St. Louis is 9h and 50min.
On the first day of the month, sunrise is at 7:18 am and sunset at 4:49 pm. On the last day of January, in St. Louis, Missouri, sunrise is at 7:07 am and sunset at 5:20 pm CST.

Sunshine

The average sunshine in January in St. Louis, Missouri, is 5.2h.

UV index

The months with the lowest UV index in St. Louis are January and December, with an average maximum UV index of 2. A UV Index value of 2, and less, symbolizes a minimal health hazard from unprotected exposure to Sun's UV rays for the average person.
Note: The daily high UV index of 2 in January translates into this advice:
Prolonged sun exposure generally does not trouble most people. However, it is vital to ensure protection for babies, children, and individuals with sensitive skin. Direct exposure to the Sun's intense radiation around midday should be avoided for health reasons. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes. Be advised! The UV radiation from the Sun can be almost doubled due to the reflective properties of snow.
[Resources]

Frequently asked questions

What are the coldest months in St. Louis?

St. Louis's coldest weather arrives in January, when temperatures average a high of 39.9°F (4.4°C) and a low of 23.7°F (-4.6°C).

How cold is it in St. Louis in January?

The high-temperature in St. Louis during January is 39.9°F (4.4°C) and the low-temperature is 23.7°F (-4.6°C).

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

In St. Louis, the average relative humidity in January is 73%.

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

In January, in St. Louis, Missouri, the rain falls for 8.9 days. Throughout January, 2.4" (61mm) of precipitation is accumulated.

What is the snowiest month in St. Louis?

The month with the most snowfall in St. Louis is January, when snow falls for 4.7 days and typically aggregates up to 5.59" (142mm) of snow.

How much does it snow in St. Louis in January?

In St. Louis, in January, snow falls for 4.7 days, with typically accumulated 5.59" (142mm) of snow.

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

In January, the average day length is 9h and 50min.

When are sunrise and sunset in January in St. Louis?

On the first day of January, sunrise is at 7:18 am and sunset at 4:49 pm. On the last day of the month, sunrise is at 7:07 am and sunset at 5:20 pm CST.

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

In St. Louis, the average sunshine duration in January is 5.2h.

What is the month with the lowest UV index in St. Louis?

January and December, with an average maximum UV index of 2, are months with the lowest UV index.

What is the UV index reading in January in St. Louis?

In St. Louis, Missouri, the average daily maximum UV index in January is 2. A UV Index estimate of 2, and below, represents a minimal hazard to health from exposure to the Sun's UV radiation.
Today
Tomorrow
Long-term
YearJanuaryFMAMJJASOND
Dec
January
Feb
Average high temperature
42.5°F 5.8°C
39.9°F 4.4°C
45°F 7.2°C
Average low temperature
26.9°F -2.8°C
23.7°F -4.6°C
27.6°F -2.4°C
Average humidity
75.8%
73%
72%
Average rainfall
2.8" 71mm
2.4" 61mm
2.2" 56mm
Average rainfall days
9.4
8.9
8
Average snowfall
4.4" 112mm
5.6" 142mm
4.3" 109mm
Average snowfall days
3.7
4.7
3.4
Average daylight
9h 3min
9h 5min
10h 5min
Average sunshine
4h 1min
5h 1min
5h 4min
Average UV index
2
2
3

Average temperature in January
St. Louis, MO

Average temperature in January - St. Louis, MO
  • Average high temperature in January: 39.9°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 January: 23.7°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).

[Resources]

Average humidity in January
St. Louis, MO

Average humidity in January - St. Louis, MO
  • Average humidity in January: 73%

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

[Resources]

Average rainfall in January
St. Louis, MO

Average rainfall in January - St. Louis, MO
  • Average rainfall in January: 2.4"

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

[Resources]

Average rainfall days in January
St. Louis, MO

Average rainfall days in January - St. Louis, MO
  • Average rainfall days in January: 8.9 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).

[Resources]

Average snowfall in January
St. Louis, MO

Average snowfall in January - St. Louis, MO
  • Average snowfall in January: 5.6"

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

[Resources]

Average snowfall days in January
St. Louis, MO

Average snowfall days in January - St. Louis, MO
  • Average snowfall days in January: 4.7 days

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

[Resources]

Average daylight in January /
Average sunshine in January
St. Louis, MO

Average daylight in January / Average sunshine in January - St. Louis, MO
  • Average daylight in January: 9h and 5min

The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).

  • Average sunshine in January: 5h and 1min

The month with the most sunshine is July (Average sunshine: 10h and 0min).
The month with the least sunshine is December (Average sunshine: 4h and 12min).

[Resources]

Average UV index in January
St. Louis, MO

Average UV index in January - St. Louis, MO
  • Average UV index in January: 2

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

[Resources]

St. Louis, Missouri, USA

Weather forecast for today
Weather forecast for tomorrow
10 days weather forecast
Climate data
1January
2February
3March
4April
5May
6June
7July
8August
9September
10October
11November
12December

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location