Gateway Arch Weather: Forecasts, Climate, and Current Conditions
Gateway Arch stands along the Mississippi River in St. Louis, Missouri, right in the heart of the North American continent. That location gives it a humid continental climate: hot, muggy summers, cold winters with possible snow, stormy springs, and often bright autumns. The four seasons are sharply defined, with little in the way of a gentle transition.
Current readings are unavailable. See the seasonal averages farther down this page.
Open-Meteo readings · updating… · park time zone
Gateway Arch Climate Month by Month
The table below shows average daily temperatures (including nighttime) and normal sunshine levels in St. Louis, based on NOAA records:
| Month | Average temperature | Sunshine |
|---|---|---|
| January | 29°F | 50% |
| February | 34°F | 52% |
| March | 45°F | 54% |
| April | 57°F | 56% |
| May | 66°F | 59% |
| June | 75°F | 66% |
| July | 80°F | 68% |
| August | 78°F | 65% |
| September | 70°F | 63% |
| October | 58°F | 60% |
| November | 46°F | 46% |
| December | 34°F | 53% |
These averages include nighttime temperatures. Mid-afternoon temperatures run considerably higher in summer and lower in winter. November is the grayest month (46% sunshine), while July peaks at 68%. Even in January, St. Louis sees sunshine about one day out of two.
Is Gateway Arch Cold or Hot? Benchmarks and Extremes
St. Louis is a city of sharp temperature swings. Local records climb above 104°F and can approach -4°F when wind chill is factored in. The Arch itself, rising 630 feet, is especially exposed to the wind. At the top, it can feel several degrees colder than it does on the plaza, no matter the season. Keep that in mind before heading up in a T-shirt in November.
What to Wear by Season
Winter: a warm coat (down or heavy wool), hat, gloves, and waterproof shoes. If you're going to the top, add an extra layer. The wind at 630 feet doesn't let up.
Spring: several light layers and a lightweight rain jacket in your bag. Keep an eye on weather alerts. A clear morning can turn stormy by early afternoon.
Summer: lightweight, breathable clothing, a wide-brimmed hat, SPF 50+ sunscreen, sunglasses, and a bottle of water. The concrete and granite plaza reflects and amplifies the heat. Drink water regularly. Avoid direct sun from noon to 4 p.m. if you're traveling with young children.
Fall: versatile clothing and a windbreaker for cool October and November mornings. Keep it simple and practical.
Alerts and Conditions to Watch
Thunderstorms and tornado risks (April to September). Convective storms develop quickly in the region. Check National Weather Service alerts before heading out, and if a tornado warning is issued, go inside the Visitor Center or museum immediately, below ground level.
Mississippi River flooding. The park borders the river. Flooding can temporarily close the plaza and green spaces, especially in spring after heavy rain or snowmelt upstream. Check conditions on the NPS website before you go.
Extreme heat (June to August). A heat index of 100 to 104°F is possible on the most humid days. Sensitive groups, including young children and older adults, should avoid the plaza in mid-afternoon and visit the air-conditioned museum instead.
Frequently Asked Questions
What is the climate like at Gateway Arch?
Gateway Arch has a humid continental climate: cold winters (an average of 29°F in January), hot and muggy summers (80°F in July), stormy springs, and mild, sunny autumns.
Is Gateway Arch cold?
Gateway Arch is cold from December through February, with average temperatures below freezing in January. At the top of the Arch (630 feet), wind makes it feel noticeably colder, even outside winter.
What should I wear to visit Gateway Arch?
Dress for the season: a down jacket and gloves in winter, layers in spring, breathable clothing and sun protection in summer, and a windbreaker in fall. Always bring an extra layer if you're going to the top.
What is the climate like in the Midwest?
The American Midwest has a continental climate: cold, snowy winters, hot and humid summers, and springs marked by severe thunderstorms. Gateway Arch in St. Louis, Missouri, is a typical example, with a temperature range of more than 50°F between January and July.