Green Mountain Reservoir — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Green Mountain Reservoir, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Green Mountain Reservoir today is 14°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 54°F (12°C) to 60°F (15°C). The water is significantly warmer, and swimming becomes possible for most people. However, caution may still be required for prolonged stays in the water, as extended exposure can cause discomfort. This is a suitable temperature range for short swims and for those accustomed to cooler water. For more comfortable swimming, it is recommended to use proper gear. It is important to note that these swimming tips and recommendations apply only in good weather. When the air temperature is below 68°F (20°C), and sometimes even below 77°F (25°C), swimming can be unpleasant even with relatively high water temperatures.
Water Temperature Chart Over the Last 30 Days
Table of Daily Sea Temperature Data
| Date | Current | Average | Forecast |
|---|---|---|---|
| SEP 15 | 15.6°C | 18.5°C | |
| SEP 16 | 15.8°C | 18.5°C | |
| SEP 17 | 15.0°C | 18.5°C | |
| SEP 18 | 15.1°C | 18.5°C | |
| SEP 19 | 15.1°C | 18.5°C | |
| SEP 20 | 14.4°C | 18.5°C | |
| SEP 21 | 14.8°C | 18.5°C | |
| SEP 22 | 14.5°C | 18.5°C | |
| SEP 23 | 18.5°C | 14.2°C | |
| SEP 24 | 18.5°C | 14.5°C | |
| SEP 25 | 18.5°C | 14.7°C | |
| SEP 26 | 18.5°C | 14.9°C | |
| SEP 27 | 18.5°C | 15.1°C | |
| SEP 28 | 18.5°C | 15.4°C | |
| SEP 29 | 18.5°C | 15.6°C |
* Current - Actual water temperature value
** Average - Average water temperature on this day in recent years
*** Forecast - Our water temperature forecast
Actual nearshore water temperatures may fluctuate by several degrees from the reported values, especially following heavy rainfall or extended periods of strong winds. Certain wind patterns can cause colder, deeper waters to rise and replace the sun-warmed surface water, leading to noticeable variations.
Our forecast is based on a proprietary mathematical model that considers real-time water temperature changes, historical trends, key weather patterns, wind strength and direction, and air temperature specific to each region. Additionally, we incorporate data from other resorts to enhance accuracy.
Monthly Water Temperature Range (Min, Max & Average)
| Month | Min | Avg | Max |
|---|---|---|---|
| January | 5°C | 10°C | 14°C |
| February | 4°C | 9°C | 14°C |
| March | 6°C | 10°C | 14°C |
| April | 4°C | 10°C | 15°C |
| May | 6°C | 12°C | 18°C |
| June | 10°C | 15°C | 20°C |
| July | 15°C | 20°C | 25°C |
| August | 16°C | 20°C | 23°C |
| September | 15°C | 19°C | 22°C |
| October | 11°C | 16°C | 20°C |
| November | 7°C | 12°C | 16°C |
| December | 6°C | 9°C | 12°C |
Green Mountain Reservoir: Water Temperature by Location
Green Mountain Reservoir: Weather Forecast
September 23
September 24
September 25
September 26
September 27
Location & Local Information
Green Mountain Reservoir, a high-elevation impoundment in Colorado, typically has cool water year-round because it is fed by snowmelt and sits at roughly 7,900 feet. Seasonal surface temperatures commonly run from about 40–55°F (4–13°C) in spring (April–June) as snowmelt dominates, warming to roughly 60–72°F (16–22°C) during the warmest part of summer (July–August) on sunny, calm days. By early fall (September–October) surface readings generally fall back into the 50–60°F (10–16°C) range, and in winter the reservoir can approach freezing, with ice forming in colder months and surface temperatures near 32°F (0°C) where open water remains.
Swimming is generally permitted in the reservoir because it is a public recreational water body, and people do enter for bathing and wading during summer. However, opportunities are limited by cold water, short warm seasons, and active boating; many visitors find only brief swims comfortable without protective gear. Safety considerations—cold-shock and hypothermia risk, deep water, and boat traffic—mean unguarded areas are common and formal beaches or lifeguards are limited. Visitors are advised to check local regulations and use caution when swimming, especially early and late in the season.