Last updated: June 24, 2025
In October, the average temperature in Helena, United States hovers around 4°C (40°F). This month can bring extremes, with temperatures dipping as low as -21°C (-6°F) and soaring up to 26°C (80°F). Expect about 41 mm (1.6 in) of precipitation spread over 10 days, contributing to an average humidity of 72%.
In October in Helena, the average temperature is 4°C (40°F), with maximums reaching 26°C (80°F) and minimums dipping as low as -21°C (-6°F). Travelers should be prepared for a wide range of temperatures and pack accordingly.
In Helena in October, the precipitation amount is 41 mm (1.6 in) spread over 10 days.
In Helena in October, humidity is 72%. With an average temperature of 4°C (40°F), this humidity feels like an uncomfortable chill that seeps into your bones, making outdoor activities challenging for travelers unaccustomed to such damp conditions.
In Helena in October, the maximum UV index reaches 5, which corresponds to a moderate Exposure Category. Under these conditions, the estimated time to burn is approximately 30 minutes. For more details, you can check the Hourly UV Index in Helena.
UV Risk Categories
Weather in Helena varies notably across the year, with each month offering distinct climate conditions. This page compares October’s weather to other months in Helena, focusing on differences in temperature, rainfall, humidity, and UV levels.
Temperature | Precipitation | Humidity | UV | |
---|---|---|---|---|
January Weather | -7°C (20°F) | 23 mm (0.9 inches) | 87% | moderate |
February Weather | -9°C (16°F) | 51 mm (2.0 inches) | 88% | moderate |
March Weather | -2°C (29°F) | 38 mm (1.5 inches) | 83% | high |
April Weather | 2°C (36°F) | 67 mm (2.7 inches) | 78% | very high |
May Weather | 9°C (48°F) | 88 mm (3.5 inches) | 76% | very high |
June Weather | 14°C (58°F) | 107 mm (4.2 inches) | 78% | extreme |
July Weather | 19°C (67°F) | 31 mm (1.2 inches) | 77% | very high |
August Weather | 18°C (65°F) | 34 mm (1.3 inches) | 71% | very high |
September Weather | 13°C (55°F) | 44 mm (1.7 inches) | 68% | very high |
October Weather | 4°C (40°F) | 41 mm (1.6 inches) | 72% | moderate |
November Weather | -1°C (30°F) | 33 mm (1.3 inches) | 84% | moderate |
December Weather | -6°C (21°F) | 33 mm (1.3 inches) | 90% | low |