Summer and Fall
Depending on the past winter, snow can remain in Cunningham Gulch late in the year. In early summer, take caution as the runoff in the streams is high, which makes the multiple stream crossings (both on the trail and driving to the trailhead) tricky. The photos provided were taken on July 4th weekend, and there was still significant snow above 12,000ft.
Late July through August is ideal for wildflower viewing, as the open grassland is filled with colonies of paintbrush, columbine, king's crown, alpine blue violet, alpine sunflower, and many more.
Be mindful of summer thunderstorms, as the majority of this hike is exposed and well above treeline. Get an early start and keep an eye out for clouds forming, as storms can appear very abruptly.