Last updated: June 24, 2025
In September, the average temperature in West Haven-Sylvan, United States hovers around 18°C (64°F). Expect a range where minimums can dip to 6°C (42°F) and maximums soar to 35°C (95°F). During this month, you can anticipate about 62 mm (2.4 in) of precipitation over 8 days, contributing to an average humidity of 71%.
In September in West Haven-Sylvan, the average temperature is 18°C (64°F). Maximum temperatures can reach 35°C (95°F), while minimums can drop as low as 6°C (42°F). This variability makes it essential for travelers to pack both light clothing for warm days and warmer layers for cooler evenings.
In West Haven-Sylvan in September, the precipitation amount is 62 mm (2.4 in) over the course of 8 days.
In West Haven-Sylvan in September, humidity is 71%. With an average temperature of 18°C (64°F), this humidity feels like a warm embrace, making traveling a bit sticky but still pleasant as the warmth envelops you, urging you to explore the vibrant surroundings while staying hydrated.
In West Haven-Sylvan in September, the maximum UV index is 7, which corresponds to the high Exposure Category. This means that the time to burn is approximately 25 minutes. For more detailed information, you can check the Hourly UV Index in West Haven-Sylvan.
UV Risk Categories
Weather in West Haven-Sylvan varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in West Haven-Sylvan, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 5°C (42°F) | 163 mm (6.4 inches) | 85% | low |
| February Weather | 5°C (41°F) | 172 mm (6.8 inches) | 84% | moderate |
| March Weather | 8°C (46°F) | 135 mm (5.3 inches) | 85% | moderate |
| April Weather | 11°C (51°F) | 117 mm (4.6 inches) | 83% | high |
| May Weather | 14°C (58°F) | 58 mm (2.3 inches) | 83% | very high |
| June Weather | 18°C (64°F) | 46 mm (1.8 inches) | 83% | very high |
| July Weather | 21°C (69°F) | 6 mm (0.2 inches) | 82% | very high |
| August Weather | 21°C (70°F) | 8 mm (0.3 inches) | 74% | very high |
| September Weather | 18°C (64°F) | 62 mm (2.4 inches) | 71% | high |
| October Weather | 12°C (53°F) | 105 mm (4.1 inches) | 81% | moderate |
| November Weather | 8°C (47°F) | 155 mm (6.1 inches) | 87% | moderate |
| December Weather | 5°C (41°F) | 183 mm (7.2 inches) | 87% | low |