Halfmoon Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Halfmoon Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Halfmoon Lake today is 19.6°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 |
|---|---|---|---|
| SEP 14 | 19.7°C | 22.5°C | |
| SEP 15 | 20.3°C | 22.5°C | |
| SEP 16 | 19.1°C | 22.5°C | |
| SEP 17 | 19.3°C | 22.5°C | |
| SEP 18 | 19.7°C | 22.5°C | |
| SEP 19 | 19.9°C | 22.5°C | |
| SEP 20 | 19.8°C | 22.5°C | |
| SEP 22 | 22.5°C | 19.7°C | |
| SEP 23 | 22.5°C | 19.9°C | |
| SEP 24 | 22.5°C | 20.0°C | |
| SEP 25 | 22.5°C | 20.2°C | |
| SEP 26 | 22.5°C | 20.3°C | |
| SEP 27 | 22.5°C | 20.5°C | |
| SEP 28 | 22.5°C | 20.6°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 | 4°C |
| February | 0°C | 2°C | 5°C |
| March | 1°C | 5°C | 8°C |
| April | 3°C | 8°C | 14°C |
| May | 10°C | 14°C | 19°C |
| June | 16°C | 20°C | 25°C |
| July | 20°C | 24°C | 27°C |
| August | 20°C | 24°C | 28°C |
| September | 18°C | 23°C | 27°C |
| October | 14°C | 18°C | 21°C |
| November | 4°C | 9°C | 14°C |
| December | 0°C | 3°C | 6°C |
Halfmoon Lake: Water Temperature by Location
Halfmoon Lake: Weather Forecast
September 21
September 22
September 23
September 24
September 25
Location & Local Information
Halfmoon Lake in Michigan experiences typical inland-lake temperature swings through the year. In spring the surface water generally warms from near-freezing up to roughly 40–60°F (4–15°C) as ice melts and air temperatures rise. Summer brings the warmest conditions, with daytime surface temperatures commonly between 70–80°F (21–27°C) during July and August at popular swimming depths; shallower bays can be a few degrees warmer on hot, calm days. In early fall the water cools back into the 50–65°F range (10–18°C) and by late fall and winter the surface drops toward freezing, about 32–40°F (0–4°C), often forming lake ice while deeper water remains near the 39°F (4°C) density maximum.
Swimming is generally permitted at Halfmoon Lake where public access points, beaches, or private properties designate recreation areas, because it is a natural inland lake commonly used for swimming and boating. Local rules, property ownership, posted signage, and periodic water-quality advisories determine specific access and safety. Users should check for swim advisories, harmful algal blooms, or no-swim notices, be mindful of cooler shoulder-season temperatures that increase hypothermia risk, and follow lifeguard or local guidance when present.