Mt. Rainier – Disappointment Cleaver

The weather window is the story here, and it's a good one. Friday through Sunday are all mostly sunny with surface winds under 21 mph. At summit elevation (~14,411 ft), expect ridge winds roughly double the surface forecast — so Saturday's 21 mph surface W winds translate to maybe 35-42 mph at the crater rim. That's manageable but worth monitoring; plan your summit push for early Saturday morning when the overnight surface winds are sitting at 12 mph or less, which keeps ridgeline winds in the 20-25 mph range. Sunday is slightly calmer aloft and also viable. The hard stop is Sunday night — 44% precip chance with rain/snow mix means deteriorating conditions arriving overnight Sunday. If you're not off the Ingraham Flats by Sunday afternoon, you're racing that system.

Freezing levels aren't explicitly in the forecast data, but with surface lows of 35°F at valley elevation and standard lapse rates, expect the freezing level around 8,000-9,000 ft on warm afternoons. The DC route climbs from Camp Muir (~10,188 ft) to the summit at 14,411 ft, so you'll be entirely above the freezing level during your summit push — good for firm snow conditions. The approach to Muir from Paradise (~5,400 ft) will see some softening on south-facing aspects in the afternoon, so descend from Muir back to Paradise before 1 PM to avoid post-holing through deteriorating snow.

Avalanche danger carries no official rating from NWAC right now — this is a late-season condition, not a data gap. The bulletin advises watching for field signs: recent debris, shooting cracks, whumpfing. The DC route crosses below the cleaver and traverses the Ingraham Glacier where isolated wet slab or cornice activity is possible in the warm afternoon hours. Start your summit push by 1-2 AM from Muir so you're through the exposed sections before afternoon solar heating. Long Lake SNOTEL at 840 ft is showing 61 inches depth and falling SWE, confirming active melt at lower elevations — that melt signal doesn't extend to summit elevations, but it confirms the afternoon sun has real heat in it.

Logistically, you've got 15+ hours of daylight and a clean weather window Friday and Saturday. Alpine start from Muir at 1 AM Friday or Saturday puts you on the summit around 7-8 AM and back at Muir well before the afternoon softening window. Stream crossings on the Paradise approach are normal, fires are zero concern. This is a solid window — execute the early start and get off the upper mountain before the Sunday night system arrives.