Bottom line: This click-map point forecast from the NOAA web site is your best weather resource for a day hike in the Enchantments.
Everyone wants a bluebird day to do their thru hike in the Enchantment Lakes Basin. The mountain scenery is beautiful in Washington’s clear summer weather.
After making all the plans, booking the shuttle, getting fit, and getting your friends psyched, do you really want to cancel your hike due to rain? Maybe. Here are some things to consider about Enchantments weather.
First, even with a clear forecast, the Cascade Mountains make their own weather. The forecast might call for sunshine, but you find yourself in a cloud at 7,000 feet unable to see 100 feet in front of you from under the hood of your rain shell.
The Enchantments are several thousand feet higher than the town of Leavenworth Washington. So the temperature in the Enchantments naturally will be cooler than the forecast for the nearest town.
How much cooler? About 3°C per thousand feet, generally speaking. If it’s 80°F in Leavenworth (1200 feet), it’s likely to be closer to 67°F at Isolation Lake (7700 feet).
You can eliminate some of the guesswork by retrieving a weather forecast for the Enchantments Core. The NOAA website at weather.gov allows you to make a user defined area forecast.
You can pinpoint a lake or trail and get an accurate forecast for that location. Here’s an example for the top of Aasgard Pass:
Regardless of the forecast for your chosen day, be prepared for a sudden change in weather. It can get cooler and wetter. Or miserably hot. It can even snow unexpectedly.