Temperature:

Your Favorite Locations:

Your favorites list is empty.

Lewis Lake — Current Water Temperature, Annual Trends and Forecast

This page provides information on the current water temperature in Lewis Lake, trends, monthly ranges and the forecast for the coming days.

Henrys Lake, United States
Henrys Lake, United States © By Idaho Parks, CC BY-SA 3.0

Current Water Temperature

11.2°C
Today
10.4°C
Yesterday
10.3°C
A Week Ago
Get instant access to real-time water temperatures for this and all other locations with our iOS and Android apps.

Water Temperature in Lewis Lake today is 11.2°C.

Water Temperature: Daily Trends, Historical Records, and Forecast

❌ As of today, the minimum water temperature ranges from 50°F (10°C) to 54°F (12°C). The water is slightly warmer, but still cool for most people. Swimming in such conditions is possible, but for most people, the time spent in the water should be limited to avoid hypothermia. Even experienced swimmers may feel discomfort if they stay in the water for too long. To improve comfort and safety, a wetsuit can be used. 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

From May 10 to June 10

Table of Daily Sea Temperature Data

Date Current Average Forecast
JUN 28.5°C10.5°C
JUN 38.6°C10.5°C
JUN 48.8°C10.5°C
JUN 59.3°C10.5°C
JUN 69.8°C10.5°C
JUN 710.4°C10.5°C
JUN 810.5°C10.5°C
JUN 1010.5°C11.2°C
JUN 1110.5°C11.1°C
JUN 1210.5°C11.1°C
JUN 1310.5°C11.1°C
JUN 1410.5°C11.0°C
JUN 1510.5°C11.0°C
JUN 1610.5°C11.0°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
January0°C4°C6°C
February1°C4°C7°C
March1°C5°C9°C
April0°C3°C5°C
May2°C6°C11°C
June7°C11°C14°C
July12°C17°C21°C
August14°C18°C22°C
September11°C15°C18°C
October4°C8°C12°C
November2°C6°C10°C
December1°C4°C7°C

Lewis Lake: Water Temperature by Location

Lewis Lake: Weather Forecast

June 9

° / °
moderate rain showers
rain: 69% | wind:

June 10

° / °
heavy snow shower
snow: 69% | wind:

June 11

° / °
slight snow shower
snow: 57% | wind:

June 12

° / °
overcast
snow: 30% | wind:

Location & Local Information

Lewis Lake, located in the high country of Wyoming’s Teton region, is a classic mountain lake with water temperatures that reflect its elevation, seasonal snowmelt and cool alpine climate. In spring (May–June) surface temperatures commonly sit between about 35–50°F (2–10°C) as snowmelt feeds the lake and warming is limited. By mid to late summer (July–August) the warmest months, sheltered bays and sun-warmed surface layers can reach roughly 55–68°F (13–20°C) on a typical year, though deeper water remains much colder. Early fall (September) temperatures generally fall back to about 45–60°F (7–15°C) as nights cool and inflows increase, and in winter the lake is often ice-covered with water at or just above freezing, around 32–39°F (0–4°C) beneath the ice.

Swimming at Lewis Lake is permitted in the sense that there are no formal bans, but practical safety considerations strongly affect whether people choose to enter the water. The lake’s high elevation, cold temperatures even in summer, and rapidly changing mountain weather mean hypothermia is a real risk; there are no lifeguards or extensive beach facilities, and boat traffic can be present. Short dips or swims using thermal protection like a wetsuit are the usual approach for those who enter the water, while most visitors enjoy the shoreline, fishing and views rather than prolonged immersion.

Nearby Lakes

Frequently Asked Questions

What is the current water temperature in Lewis Lake?
Water Temperature in Lewis Lake today is 11.2°C.
What is the water temperature in Lewis Lake during the summer months?
The water temperature in Lewis Lake in summer fluctuates in the range of 7°C - 22°C.
Is it possible to swim in Lewis Lake and what are the possibilities for this?
Yes, it's possible to swim in Lewis Lake, Wyoming. However, due to cold temperatures and possible underwater thermal features, the National Park Service discourages it.