Last updated: June 24, 2025
In April, the average temperature in Saint Louis, United States hovers around 7°C (46°F). Expect a wide range, with minimums dipping to -9°C (17°F) and maximums soaring to 28°C (83°F). Precipitation is relatively significant, totaling 86 mm (3.4 in) over 12 days, while the average humidity remains high at 86%.
In April in Saint Louis, the average temperature is 7°C (46°F), with maximums reaching up to 28°C (83°F) and minimums dropping as low as -9°C (17°F). This wide temperature range means travelers should pack for both warm and chilly conditions.
In Saint Louis in April, the precipitation amount is 86 mm (3.4 in) over a span of 12 days.
In Saint Louis in April humidity is 86%. With an average temperature of 7°C (46°F), this humidity feels like wrapping yourself in a damp blanket, making travel uncomfortable and heavy, as the cold air mixes with the muggy atmosphere, leaving you longing for a warm, dry refuge.
In Saint Louis in April, the maximum UV index is 8, which corresponds to a very high Exposure Category. This means that the time to burn is only 15 minutes. For more detailed information, you can refer to the Hourly UV Index in Saint Louis.
UV Risk Categories
Weather in Saint Louis varies notably across the year, with each month offering distinct climate conditions. This page compares April’s weather to other months in Saint Louis, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -4°C (24°F) | 55 mm (2.2 inches) | 88% | low |
| February Weather | -4°C (25°F) | 59 mm (2.3 inches) | 87% | moderate |
| March Weather | 2°C (35°F) | 58 mm (2.3 inches) | 85% | moderate |
| April Weather | 7°C (46°F) | 86 mm (3.4 inches) | 86% | very high |
| May Weather | 15°C (59°F) | 115 mm (4.5 inches) | 80% | very high |
| June Weather | 20°C (69°F) | 113 mm (4.5 inches) | 80% | very high |
| July Weather | 23°C (74°F) | 67 mm (2.7 inches) | 80% | very high |
| August Weather | 22°C (71°F) | 81 mm (3.2 inches) | 80% | very high |
| September Weather | 18°C (64°F) | 98 mm (3.9 inches) | 80% | high |
| October Weather | 11°C (52°F) | 120 mm (4.7 inches) | 84% | moderate |
| November Weather | 3°C (38°F) | 57 mm (2.2 inches) | 89% | moderate |
| December Weather | -1°C (31°F) | 63 mm (2.5 inches) | 86% | low |