Portage Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Portage Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Portage Lake today is 17.9°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 60°F (15°C) to 65°F (18°C). The water is comfortable for most people, making it an ideal range for water sports enthusiasts. The temperature does not cause significant discomfort, and swimming will be pleasant for the majority. However, it's important to remember that prolonged exposure to the water can still lead to cooling, so it's essential to monitor the time spent in the water, especially for children or elderly people. 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 3 | 14.7°C | 17.0°C | |
| JUN 4 | 14.2°C | 17.0°C | |
| JUN 5 | 15.3°C | 17.0°C | |
| JUN 6 | 15.8°C | 17.0°C | |
| JUN 7 | 16.4°C | 17.0°C | |
| JUN 8 | 17.6°C | 17.0°C | |
| JUN 10 | 17.9°C | 17.0°C | |
| JUN 11 | 17.0°C | 17.9°C | |
| JUN 12 | 17.0°C | 17.8°C | |
| JUN 13 | 17.0°C | 17.8°C | |
| JUN 14 | 17.0°C | 17.7°C | |
| JUN 15 | 17.0°C | 17.7°C | |
| JUN 16 | 17.0°C | 17.6°C | |
| JUN 17 | 17.0°C | 17.6°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 | 0°C | 1°C | 3°C |
| February | 0°C | 1°C | 3°C |
| March | 0°C | 2°C | 4°C |
| April | 1°C | 5°C | 8°C |
| May | 6°C | 11°C | 16°C |
| June | 13°C | 17°C | 21°C |
| July | 15°C | 21°C | 27°C |
| August | 17°C | 24°C | 30°C |
| September | 14°C | 16°C | 19°C |
| October | 9°C | 12°C | 15°C |
| November | 3°C | 7°C | 10°C |
| December | 0°C | 2°C | 4°C |
Portage Lake: Water Temperature by Location
Portage Lake: Weather Forecast
June 9
June 10
June 11
June 12
June 13
Location & Local Information
Portage Lake in Michigan experiences a typical northern inland-lake temperature pattern. In spring (April–May) surface temperatures often run from about 40–60°F (4–15°C) as the water slowly warms after ice-out. Summer (June–August) brings the warmest conditions, with surface readings commonly between 65–78°F (18–26°C) in open water and warmer still in shallow bays during heat spells. By fall (September–November) temperatures fall back to roughly 50–60°F (10–16°C) and decline toward near-freezing in winter; once ice forms the water under the ice is close to 32–39°F (0–4°C).
Swimming is generally allowed at public access sites on Portage Lake because the lake is used for recreation, but local rules, posted signs and water-quality advisories should be checked before entering. Summer is the most comfortable season for swimming, but occasional harmful algal blooms, boat traffic, low visibility and lack of lifeguards can make some spots unsafe at times. In winter the water is far too cold and often ice-covered, so swimming is not appropriate unless properly controlled ice-swim activities are organized with safety measures in place.