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How the scores work

Every score is a number from 0 to 100 computed fresh each day from 16-day forecast data. There's no single "conditions" number — skiing styles have completely different ideal conditions, so we score each separately. Here's exactly what goes into each one.

❄️

Powder

Measures how good conditions are for finding fresh, untracked snow. Weighted heavily toward recent and incoming snowfall, with bonuses for cold temperatures that keep snow dry and light winds that leave it undisturbed.

Factor	Weight	What we look for
New snow last 48h	Primary	More is better — recent, deep snow means fresh untracked lines and buried tracks
Forecast snow next 24h	Moderate	Active storm window — more incoming extends powder life through the day
Temperature	Moderate	Well below freezing — cold snow stays dry, light, and slow to bond and track out
Wind speed	Minor	Calm — keeps untracked lines intact and deposits undisturbed

🎿

Carving

Measures how good conditions are for edge-to-edge runs on groomed hardpack. Prioritizes overnight freezing that firms up the surface and calm mornings before it softens. Penalizes rain, flat light, and warm overnight temps that turn groomers to slush. Incorporates confirmed grooming data from Vail Resorts, Alterra, and Alta where available.

Factor	Weight	What we look for
Overnight low temperature	Primary	Mid-20s°F — firms the groomed surface without freezing it to bulletproof ice
Morning temperature (7–11 AM)	Primary	Upper teens to low 30s°F — hardpack sweet spot before midday sun softens it
Wind speed	Moderate	Light breeze — helps firm soft edges near freezing; strong gusts always hurt
Visibility / flat light (8 AM–4 PM)	Moderate	Clear sky — flat light makes it hard to read groomer texture at speed
Precipitation type	Moderate	No rain — rain above freezing degrades the groomed surface quickly
Grooming data	Moderate	Confirmed groomed runs from resort data — no adjustment when data unavailable
Snow recency	Minor	Dry packed base — no recent snow is ideal; heavy recent snow penalizes the score

Note: Very cold overnights can freeze the surface to bulletproof ice rather than firm corduroy — conditions typically improve as solar warming builds through the morning. Overnight temps above freezing mean the groomer went soft. Grooming adjustment applies to today and tomorrow only; resorts without confirmed grooming data receive no adjustment.

🔭

Visibility

Measures how clear the mountain is. Rewards bluebird days with calm winds and no precipitation. Penalizes active storms, heavy snowfall (even if good for powder), high winds, and fog.

Factor	Weight	What we look for
Weather conditions (cloud cover, fog, storm type)	Primary	Clear sky — full blue sky, high contrast terrain, maximum visibility
Wind speed	Primary	Below 10 mph — no blowing snow or whiteout risk at the surface
Snowfall during ski hours (8 AM–4 PM)	Moderate	No snowfall — even light snow reduces terrain contrast and depth perception

Note: Fog scores near zero. Overcast (flat light) scores significantly lower than partly cloudy — the inability to read groomer texture or judge speed is a real hazard at high pace.

🛹

Park

Measures how good conditions are for jumps, rails, and jibs. Derived from a weighted blend of carving (surface firmness), visibility (seeing landings), and powder (feature coverage), with a discount applied — park conditions are rarely as clean as a pure powder or carving day.

Factor	Weight	What we look for
Carving score (surface quality)	Primary	Firm but not icy — consistent takeoffs and predictable landings
Visibility score (seeing landings)	Moderate	Clear enough to read features and judge speed on approach
Powder score (feature coverage)	Moderate	Recent snow refreshes landings and fills in features

Note: Derived from carving, visibility, and powder scores with a moderate discount applied — park conditions rarely match a perfect powder or carving day even when the underlying factors look strong.

In-app: hour-by-hour conditions. The factors above describe the daily forecast model used for the 16-day view. Inside the app, conditions are also modeled hour by hour using a more detailed surface physics approach — accounting for how the groomed surface evolves through the freeze-thaw cycle as the sun moves across the slope. The timeline shows how each score changes through the ski day and highlights the best window automatically.

Data sources

Weather forecasts — 16-day hourly and daily forecast from Open-Meteo (CC BY 4.0), using best-match resort coordinates and summit elevation.
Snow depth & base conditions — Current base depth from NOAA SNODAS (National Snow and Ice Data Center).
Grooming reports — Confirmed overnight grooming from Vail Resorts, Alterra Mountain Company, and Alta. Applied to today and tomorrow's carving scores only.
Resort data — 813 North American ski resorts from OpenSkiMap contributors (ODbL).

Update cadence

Scores for every active resort are recomputed hourly. A nightly job pre-warms all 813 resorts so the first morning load is instant. Scores shown in the app reflect conditions as of the last cache refresh — typically within the hour.