St. Louis, MO weather by month
Midwest · Station: Lambert–St. Louis International Airport, MO · NOAA 1991–2020 Climate Normals
The best time to visit St. Louis, MO is September–October, when average daytime highs are comfortable and rainfall sits at or below the city's monthly average. St. Louis is hottest in July (avg high 90°F) and coolest in January (avg high 40°F). The wettest month is May (4.8 in) and the driest is February (2.2 in). Overall the annual mean temperature is about 57.5°F with 41.7 in of precipitation a year and 16.6 in of snow.
Source: NOAA NCEI U.S. Climate Normals 1991–2020. Data as of June 2026.
Monthly weather averages for St. Louis
| Month | Avg high (°F) | Avg low (°F) | Avg precip (in) | Avg snow (in) |
|---|---|---|---|---|
| January | 40 | 24 | 2.6 | 5.7 |
| February | 46 | 28 | 2.2 | 4.3 |
| March | 57 | 37 | 3.5 | 2.3 |
| April | 68 | 47 | 4.7 | 0.2 |
| May | 77 | 58 | 4.8 | 0 |
| June | 86 | 67 | 4.5 | 0 |
| July | 90 | 71 | 3.9 | 0 |
| August | 88 | 69 | 3.4 | 0 |
| September | 81 | 61 | 3 | 0 |
| October | 69 | 49 | 3.2 | 0 |
| November | 56 | 37 | 3.4 | 0.9 |
| December | 45 | 29 | 2.5 | 3.2 |
Source: NOAA NCEI U.S. Climate Normals 1991–2020. Data as of June 2026.
Best time to visit St. Louis
Based on the normals above, the most pleasant window is September–October. In those months daytime highs are in the mild-to-warm range and precipitation is no higher than the city's typical month, so you avoid both the peak hot of July (when highs reach about 90°F — stay hydrated and seek shade midday) and the cool, darker conditions around January (highs near 40°F). Try to avoid May if rain would spoil your plans — it is the wettest month at 4.8 in. Use the packing & comfort tool to check any specific month.
How St. Louis compares
St. Louis's 41.7 in of annual precipitation and 57.5°F mean temperature put it in context with other US cities. See where it ranks for warmest in January, rainiest overall and driest overall, or browse the full list of cities.
Frequently asked questions
What is the best time to visit St. Louis?
The most comfortable time to visit St. Louis, MO is September–October, when average daytime highs are mild and rainfall is at or below the city's average. St. Louis is hottest in July (avg high 90°F) and coolest in January (avg high 40°F), per NOAA 1991–2020 Climate Normals.
What is the average temperature in St. Louis?
St. Louis's annual mean temperature is about 57.5°F. The warmest month is July (average high 90°F, low 71°F) and the coolest is January (average high 40°F, low 24°F).
How much rain does St. Louis get?
St. Louis receives about 41.7 inches of precipitation a year. The wettest month is May (4.8 in) and the driest is February (2.2 in).
Does it snow in St. Louis?
Yes. St. Louis averages about 16.6 inches of snow a year. Snow normally falls between late autumn and early spring; summer months see none.
Source
Monthly averages from the NOAA NCEI U.S. Climate Normals 1991–2020, station Lambert–St. Louis International Airport, MO (reference values verified against the published normals). Climate normals describe a 30-year average, not a forecast; any individual year can differ. See our methodology for how "best time to visit" is derived.
Last updated: 2026-06-18