Last updated: June 24, 2025
In Valparaiso, United States, the average temperature in September is a pleasant 21°C (70°F). However, temperatures can vary significantly, with a minimum of 6°C (42°F) and a maximum soaring to 36°C (98°F). Expect about 80 mm (3.2 in) of precipitation spread over 8 days, contributing to an average humidity level of 75%. Whether you're enjoying a sunny day or a rainy afternoon, be prepared for a mix of weather in this vibrant destination!
In September in Valparaiso, the average temperature is 21°C (70°F), with maximums reaching 36°C (98°F) and minimums dipping as low as 6°C (42°F). Be sure to pack both light clothing and warmer layers to accommodate these temperature fluctuations during your travels.
In Valparaiso in September, the total precipitation amount is 80 mm (3.2 in), occurring over a span of 8 days.
In Valparaiso in September, humidity is 75%. With an average temperature of 21°C (70°F), this humidity feels like a warm, enveloping blanket that makes exploring the area feel slightly sticky, requiring travelers to stay hydrated and take occasional breaks in the shade to fully enjoy their adventures.
In Valparaiso 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 Valparaiso.
UV Risk Categories
Weather in Valparaiso varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Valparaiso, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -3°C (26°F) | 33 mm (1.3 inches) | 76% | moderate |
| February Weather | -3°C (26°F) | 27 mm (1.1 inches) | 80% | moderate |
| March Weather | 5°C (42°F) | 98 mm (3.8 inches) | 73% | high |
| April Weather | 10°C (51°F) | 48 mm (1.9 inches) | 74% | very high |
| May Weather | 17°C (63°F) | 139 mm (5.5 inches) | 78% | very high |
| June Weather | 25°C (77°F) | 108 mm (4.3 inches) | 82% | very high |
| July Weather | 26°C (79°F) | 74 mm (2.9 inches) | 83% | very high |
| August Weather | 24°C (76°F) | 92 mm (3.6 inches) | 80% | very high |
| September Weather | 21°C (70°F) | 80 mm (3.2 inches) | 75% | very high |
| October Weather | 12°C (53°F) | 115 mm (4.5 inches) | 75% | high |
| November Weather | 5°C (41°F) | 29 mm (1.1 inches) | 82% | moderate |
| December Weather | 0°C (32°F) | 41 mm (1.6 inches) | 83% | low |