Glendo Reservoir — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Glendo Reservoir, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Glendo Reservoir today is 19.8°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 65°F (18°C) to 68°F (20°C). This is already quite warm water, which is ideal for most people. Swimming becomes comfortable, and prolonged stays in the water do not cause discomfort. This temperature is perfect for family trips and for those who prefer warmer water. It is also comfortable for water sports such as surfing or swimming. 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 |
|---|---|---|---|
| JUN 2 | 18.8°C | 18.0°C | |
| JUN 3 | 18.7°C | 18.0°C | |
| JUN 4 | 18.8°C | 18.0°C | |
| JUN 5 | 19.0°C | 18.0°C | |
| JUN 6 | 19.4°C | 18.0°C | |
| JUN 7 | 19.9°C | 18.0°C | |
| JUN 8 | 19.8°C | 18.0°C | |
| JUN 10 | 18.0°C | 19.7°C | |
| JUN 11 | 18.0°C | 19.6°C | |
| JUN 12 | 18.0°C | 19.5°C | |
| JUN 13 | 18.0°C | 19.4°C | |
| JUN 14 | 18.0°C | 19.4°C | |
| JUN 15 | 18.0°C | 19.3°C | |
| JUN 16 | 18.0°C | 19.2°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 | 0°C | 3°C | 6°C |
| February | 0°C | 3°C | 6°C |
| March | 0°C | 5°C | 11°C |
| April | 4°C | 9°C | 14°C |
| May | 8°C | 14°C | 20°C |
| June | 15°C | 18°C | 21°C |
| July | 20°C | 23°C | 26°C |
| August | 21°C | 23°C | 26°C |
| September | 17°C | 21°C | 24°C |
| October | 9°C | 14°C | 19°C |
| November | 6°C | 10°C | 14°C |
| December | 3°C | 5°C | 7°C |
Glendo Reservoir: Water Temperature by Location
Glendo Reservoir: Weather Forecast
June 9
June 10
June 11
June 12
June 13
Location & Local Information
Glendo Reservoir’s water temperature varies considerably through the year and with depth. In winter months the surface commonly hovers near freezing, roughly 33–40°F (1–4°C). Spring warming and snowmelt typically lift surface readings into the 40s and low 50s°F (4–12°C) by late spring. Summer is when the reservoir is warmest, with common surface temperatures in the mid‑60s to mid‑70s°F (18–24°C) on warm days; shallow, protected coves may warm a few degrees higher. As autumn advances the surface cools again into the 50s–60s°F (10–16°C) before returning to near‑freezing conditions in winter. Temperatures decline quickly with depth, so subsurface water remains noticeably colder than the surface even in summer.
Swimming is permitted at Glendo State Park, where there are beaches and access points, but it is generally unmanaged — there are few or no lifeguards — and swimmers are expected to take personal precautions. Seasonal conditions, fluctuating water levels, cold deeper water, and boat traffic make caution important; cold‑water shock can occur when entering unexpectedly chilly water and areas used by watercraft increase collision risk. Because of these factors, swimming is most common and safest in the warm summer months and within designated, monitored day‑use areas.