Weather data last updated: August 01, 2026 at 07:46 AM UTC
Chasm Lake Trail — 40/100 High Risk
Safety alert: Wind speed exceeds 28 mph. Not recommended today.
- Weather Comfort: 0/40
- Safety Risk: 20/30
- Seasonal Match: 20/20
- Daylight Window: 10/10
Chasm Lake Trail in Colorado is a hard-rated route that demands respect — 8.4 miles with significant elevation change up to 11,760 ft. Our daily Suitability Score helps you pick the window with the best conditions, but this trail requires self-sufficiency and solid navigation skills.
Today’s Conditions at a Glance
High-Elevation Considerations
Summit temperatures can feel 9°F cooler than the trailhead (roughly 3.5°F per 1,000 ft gained). Above 8,000 ft, watch for altitude sickness symptoms: headache, nausea, and shortness of breath. Descend if symptoms worsen.
- Start early to avoid afternoon storms on exposed ridges
- Pack insulating layers even in summer
- Carry extra water — dehydration accelerates at altitude
Exposed Ridge & Lightning Risk
Above treeline or on open ridges, you are the tallest object in a storm. Start early and plan to be off exposed sections by early afternoon when thunderstorms build.
- If you hear thunder, descend immediately — don’t wait for rain
- Avoid summits and ridgelines during lightning risk
- No shade means UV exposure is extreme — reapply sunscreen
Seasonal Guide
- Spring: Spring (Colorado): Snow may linger above 9,760 ft through May. Muddy lower sections are common. Layers essential — mornings can be near freezing.
- Summer: Summer: Start before 8 AM to beat heat and afternoon thunderstorms. Afternoon temps at 11,760 ft can still be comfortable, but exposed sections get hot quickly. Lightning risk peaks on exposed ridges after noon.
- Fall: Fall: Often the best hiking season — stable weather, fewer crowds. Shorter days mean plan turnaround times carefully after September.
- Winter: Winter: Limited daylight and potential snow/ice above 8,760 ft. Check our daily score; many trails remain accessible with traction devices.
What to Pack
- Sturdy hiking boots with ankle support
- 2+ liters of water (more in heat or for long routes)
- Snacks and electrolytes
- Sunscreen, hat, and sunglasses
- First-aid kit and whistle
- Fully charged phone + offline map backup
- Insulating mid-layer and waterproof shell
- Rain shell — storms build fast on ridges
7-Day Forecast & Hiking Suitability
| Date | High/Low | Rain | Wind | Score | Rating |
|---|---|---|---|---|---|
| 2026-07-30 | 62°F / 48°F | 20% | 33 mph | 40 | High Risk |
| 2026-07-31 | 62°F / 47°F | 10% | 16 mph | 55 | Caution |
| 2026-08-01 | 64°F / 48°F | 5% | 18 mph | 45 | High Risk |
| 2026-08-02 | 71°F / 49°F | 5% | 18 mph | 50 | Caution |
| 2026-08-03 | 78°F / 52°F | 44% | 15 mph | 40 | High Risk |
| 2026-08-04 | 72°F / 40°F | 26% | 7 mph | 68 | Caution |
| 2026-08-05 | 73°F / 44°F | 20% | 15 mph | 60 | Caution |
Trail Information
- Location: Rocky Mountain National Park, CO
- Length: 8.4 miles
- Elevation: 11760 ft
- Difficulty: Hard
Frequently Asked Questions
What is the best time to hike Chasm Lake Trail?
Review our 7-day suitability scores and seasonal match rating. Elevation and CO climate vary significantly by month.
Is Chasm Lake Trail safe to hike today?
Check today’s Suitability Score above. This is informational only — always confirm with official park sources before hiking.
What should I wear on Chasm Lake Trail?
Plan layers based on forecast highs/lows and elevation. Waterproof gear if rain probability exceeds 40%.
Disclaimer: For informational purposes only. Not professional outdoor safety advice. Always check official NPS/USFS sources before hiking. Weather data by Open-Meteo. Trail data © OpenStreetMap contributors.