Last updated: June 24, 2025
In Carlsbad, United States, the average temperature in September hovers around 25°C (78°F), offering a pleasant backdrop for your activities. Expect minimum temperatures to dip to 7°C (45°F), while the mercury can soar up to 38°C (101°F) on hotter days. Precipitation is relatively moderate, with about 73 mm (2.9 in) of rain spread over 6 days of the month, contributing to an average humidity of 67%. Whether you’re basking in the sun or enjoying the cooler evenings, this month offers a dynamic weather experience!
In September in Carlsbad, the average temperature is 25°C (78°F). Maximum temperatures can reach 38°C (101°F), while minimums can drop to as low as 7°C (45°F). This diverse temperature range makes Carlsbad an ideal destination for travelers seeking both warm days and cool evenings.
In Carlsbad in September, the precipitation amount is 73 mm (2.9 in) over a span of 6 days.
In Carlsbad in September humidity is 67%. With an average temperature of 25°C (78°F), this humidity feels like traveling through a warm, heavy blanket that wraps around you, making outdoor activities feel a bit more strenuous, but also enveloping you in a tropical embrace that can be refreshing if you take breaks in the shade.
In Carlsbad in September, the maximum UV index reaches 11, which corresponds to an extreme Exposure Category. With a time to burn of just 10 minutes, it's essential to take precautions. For more details, you can check the Hourly UV Index in Carlsbad.
UV Risk Categories
Weather in Carlsbad varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Carlsbad, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 8°C (47°F) | 23 mm (0.9 inches) | 74% | moderate |
| February Weather | 10°C (50°F) | 22 mm (0.9 inches) | 74% | high |
| March Weather | 16°C (61°F) | 48 mm (1.9 inches) | 68% | very high |
| April Weather | 19°C (67°F) | 51 mm (2.0 inches) | 70% | extreme |
| May Weather | 24°C (75°F) | 101 mm (4.0 inches) | 77% | extreme |
| June Weather | 27°C (82°F) | 47 mm (1.8 inches) | 76% | extreme |
| July Weather | 29°C (85°F) | 21 mm (0.8 inches) | 66% | extreme |
| August Weather | 29°C (84°F) | 34 mm (1.3 inches) | 60% | extreme |
| September Weather | 25°C (78°F) | 73 mm (2.9 inches) | 67% | extreme |
| October Weather | 19°C (67°F) | 51 mm (2.0 inches) | 72% | very high |
| November Weather | 13°C (56°F) | 28 mm (1.1 inches) | 83% | high |
| December Weather | 10°C (51°F) | 25 mm (1.0 inches) | 85% | moderate |