Weather in St. Louis, Missouri
Roses open on the Piedmont edge. Day 59 of spring. Read this microseason across nine climate regions →
- TodayMay 16Thunderstorm63%77°71°
- SundayMay 17Overcast—87°67°
- MondayMay 18Heavy Rain49%78°69°
- TuesdayMay 19Showers88%81°62°
- WednesdayMay 20Overcast67%69°55°
- ThursdayMay 21Light Drizzle14%65°55°
- FridayMay 22Light Drizzle20%65°55°
- PM 2.5
- 8.3 μg/m³
- PM 10
- 8.8 μg/m³
- NO₂
- 15.6 μg/m³
- Ozone
- 58.0 μg/m³
- UV Index
- 0.0 Low
When the dew is on the grass, rain will never come to pass.
- Moonrise
- 10:55 AM
- Moonset
- 1:35 AM
- In sign
- ♊︎ Gemini
Roses open on the Piedmont edge
St. Louis at a glance
- Today vs. normal: 71°F — typical for the season
- Last frost: April 8 (climatological average for this latitude)
- Microseason: 28 of 72, May 16–20
- Planting window: Direct sow okra, melons, and southern peas. Thin carrot rows.
Right now in the garden
Warm-season window is open
As of May 17, the last spring frost has passed for most years. Transplant tomatoes, peppers, eggplants, basil, and cucurbits (cucumbers, squash, melons) now. Direct-sow beans and corn into warm soil.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | — | — |
| April | lettuce, peas, spinach, radishes | — |
| May | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | tomatoes, peppers, beans, squash | tomatoes, beans, summer squash |
| August | — | tomatoes, beans, summer squash |
| September | fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| October | fall brassicas, garlic (overwinter), carrots | winter squash, tomatoes (last) |
| November | — | — |
| December | — | — |
A year in weather
July brings St. Louis its warmest temperatures at around 81°F mean, while January delivers the coldest at approximately 33°F. Precipitation follows its own pattern, with May receiving the most rainfall at 4.9 inches and February getting the least at 2.3 inches.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 33° | 2.7″ | 9 |
| February | 37° | 2.3″ | 8 |
| March | 47° | 3.6″ | 12 |
| April | 58° | 4.8″ | 16 |
| May | 68° | 4.9″ | 16 |
| June | 77° | 4.7″ | 16 |
| July | 81° | 4.2″ | 14 |
| August | 79° | 3.8″ | 13 |
| September | 72° | 3.4″ | 11 |
| October | 60° | 3.2″ | 11 |
| November | 48° | 3.7″ | 12 |
| December | 37° | 2.6″ | 9 |
Regional context
St. Louis belongs to the humid subtropical climate region, sharing temperature ranges, seasonal patterns, and growing conditions with other nearby cities in this zone.
Similar climates: Kansas City, MO, Springfield, MO, Columbia, MO, Independence, MO, Lee's Summit, MO.
Naturalist notes
Late May brings the peak blooming period for native elderberry shrubs throughout the St. Louis area.
Ruby-throated hummingbirds typically arrive in St. Louis during the first week of May as spring migration reaches its peak.
Frequently asked
- When does it freeze in St. Louis?
- Spring's last frost usually occurs around mid-April in St. Louis, while the first fall frost typically arrives around mid-November.
- What is the rainy season in St. Louis?
- May stands as the wettest month, averaging about 4.9 inches of rain, while the city receives roughly 44 inches total each year.
- What is the warmest month in St. Louis?
- July typically brings the warmest temperatures, averaging about 81°F.
- What is the coldest month in St. Louis?
- January usually delivers the coldest weather, averaging about 33°F.
- When can I start a vegetable garden in St. Louis?
- Cool-season crops like peas and lettuce can go in the ground around the last spring frost in mid-April, but warm-season crops such as tomatoes and peppers should wait 1–2 weeks after that date.
- How many rainy days does St. Louis get?
- St. Louis sees approximately 147 rainy days per year on average.
- What hardiness zone is St. Louis?
- St. Louis's USDA hardiness zone depends on its lowest average winter temperature; the USDA's online lookup tool can provide the current zone designation using the city ZIP code.
Climate
St. Louis, Missouri experiences a humid subtropical climate zone. Temperatures hover near 33°F in January while July averages 81°F, creating a 48°F seasonal swing.
Annual precipitation totals about 44 inches across roughly 147 rainy days throughout the year.
Several factors combine to shape the local climate: latitude at 38.6°N, proximity to large water bodies, and elevation. These elements determine growing patterns, frost timing, and daily weather conditions.