Sourdough Gap is good to go this year. There's only one iffy snow patch after the gap, heading north (yesterday it was getting quite slushy and slick). Flowers look to be more abundantly insane than ever and I come here every year at some time or another. Bugs were also abundant and hungry in the upper 80’s weather. This trail has been reported enough on that I won’t go into much detail but if you’ve got a bum knee or ailment that needs a polite grade of trail, free of irritating rocks and roots this is the one. It starts high (5400 ft) and gets higher (6400) for views of Rainier (in your face if you go a little further north from the gap), Adams, St. Helens and the Goat Rocks. Sheep Lake is a family kind of lake and has some nice shallow, sandy wading spots with a pleasant temperature for swimming too.
Please obey the No Camping Within 100 ft of the Lake signs!
After Sheep Lake, the trail switchbacks up to the gap through flower meadows with stunning views all the way up. Some folks scramble up for more views north at the gap and others go into MRNP about 1/4 of a mile north for a lunch spot on a bump with Rainier looming over you and Upper Crystal Lake calling to you from below (no dogs in MRNP please). But, get this straight as I’ve happened upon some confused dudes once who went miles north on the PCT trying to find the lunch spot: After the gap, the trail into MRNP and Crystal Lakes stays up and to the left, the PCT switchbacks down to the right and then heads up and north. There’s no sign at the junction where these 2 trails meet and the Green Trails map barely shows the MRNP trail and does not even show how it connects to the Crystal Lakes trail.
This is a high, dry, hot, windy area so lots of water and sunscreen will make your trek here much more pleasant.
FYI, it is no longer free to park and hike out of Chinook Pass, so bring your pass or $5.00 cash.