Last updated: June 24, 2025
In September, the average temperature in West Lafayette, United States hovers around 21°C (70°F), offering a pleasant climate. While you might enjoy temperatures as low as 5°C (42°F), be prepared for the occasional heat wave, peaking at 34°C (93°F). Expect about 65 mm (2.6 in) of rainfall over 9 days, contributing to an average humidity of 78% that adds a touch of warmth to the air. Enjoy the diverse weather of this vibrant locale!
In September in West Lafayette, the average temperature is 21°C (70°F), with maximums reaching 34°C (93°F) and minimums dropping as low as 5°C (42°F). This range makes West Lafayette a perfect destination for travelers seeking both warm days and cooler evenings.
In West Lafayette in September, the precipitation amount is 65 mm (2.6 in) over the course of 9 days.
In West Lafayette in September, humidity is 78%. With an average temperature of 21°C (70°F), this humidity feels like a warm, enveloping blanket that can leave travelers feeling sticky and slightly fatigued, making it important to stay hydrated and take frequent breaks from outdoor activities.
In West Lafayette in September, 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 West Lafayette.
UV Risk Categories
Weather in West Lafayette varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in West Lafayette, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -2°C (29°F) | 74 mm (2.9 inches) | 85% | moderate |
| February Weather | -1°C (31°F) | 77 mm (3.0 inches) | 85% | moderate |
| March Weather | 5°C (42°F) | 106 mm (4.2 inches) | 86% | high |
| April Weather | 11°C (52°F) | 97 mm (3.8 inches) | 87% | very high |
| May Weather | 18°C (64°F) | 152 mm (6.0 inches) | 81% | very high |
| June Weather | 23°C (74°F) | 100 mm (3.9 inches) | 82% | extreme |
| July Weather | 25°C (77°F) | 99 mm (3.9 inches) | 81% | very high |
| August Weather | 23°C (74°F) | 101 mm (4.0 inches) | 79% | very high |
| September Weather | 21°C (70°F) | 65 mm (2.6 inches) | 78% | very high |
| October Weather | 14°C (57°F) | 112 mm (4.4 inches) | 81% | high |
| November Weather | 5°C (41°F) | 75 mm (3.0 inches) | 89% | moderate |
| December Weather | 2°C (35°F) | 62 mm (2.4 inches) | 86% | low |