Global evidence guide · 34 destinations

Read the snow year without false precision.

Compare when snow arrives, what changes its quality, and which weather constraints can keep a helicopter on the ground.

Compare destinations See methods and sources

Three different questions

Climate, forecast and flight decision are not interchangeable.

01

What is typical?

Long-term climate evidence describes a range of past conditions, not your trip.

02

What is developing?

Forecasts and observations show the evolving storm, wind, temperature, and cloud.

03

Can today's plan work?

Pilots and guides combine local observations, terrain, aircraft limits, and alternatives.

Snow climate

A useful family name, never a quality guarantee.

Elevation, aspect, wind, storm history, and temperature often matter more than the regional label on a specific day.

Maritime

Frequent moisture, deeper bases, denser storm snow, and rapid loading.

Coastal British Columbia, Chugach, Iceland, Southern Alps

Transitional

A changing balance between maritime storms and colder continental periods.

Interior British Columbia, Tordrillos, Canterbury, Svaneti

Continental

Colder, drier snow with longer intervals that can preserve weak layers.

Tien Shan, Central Andes, Sun Valley, Central Asia

Polar

Persistent ice and snow, strong wind redistribution, and sparse observations.

Greenland and Antarctica

Measurement literacy

Four numbers that answer different questions.

A valley gauge, ridge plot, glacier, and operator tenure should never be treated as one site.

01

New snow

A timed depth observation. Wind can remove or multiply it within metres.

02

Season snowfall

The sum of measured new snow. It is not the same as maximum snow depth.

03

Snow depth

The settled snowpack at one point. Compaction can reduce it during continued snowfall.

04

Snow-water equivalent

The water stored in snow. It helps compare storms with different snow density.

Our display rule

Every snowfall value needs a source, site, elevation when available, period, method, confidence, and caveat. Otherwise, we publish the data gap.

Audit the evidence

Helicopter weather

Snow can be excellent while flying is impossible.

There is no public flyability score. Each constraint interacts with terrain and the operator's approved system.

Visibility and ceiling

Cloud can hide ridges, landing zones, terrain contrast, or the route home.

Wind and turbulence

Strength, direction, gusts, rotor, and lee effects can remove safe options.

Temperature and icing

Freezing precipitation, wet snow, and temperature affect aircraft and snowpack decisions.

Light and surface contrast

Flat light and whiteout can erase visual references even without active snowfall.

Landing-zone conditions

Loose snow, cornices, slope, rotor wash, and escape paths affect every landing.

Margins and alternatives

Fuel, range, daylight, pickup options, and changing weather shape the daily plan.

The forecast stack

Move from the large pattern to the landing zone.

  1. 01

    Synoptic pattern

    Track fronts, pressure, moisture source, temperature, and storm timing.

  2. 02

    Mountain forecast

    Read elevation-specific precipitation, wind, freezing level, cloud, and uncertainty.

  3. 03

    Observations

    Compare stations, radar, satellite, webcams, recent snowfall, and wind transport.

  4. 04

    Operator assessment

    Guides and pilots test the forecast against local terrain and direct observations.

  5. 05

    Continuous reassessment

    The plan changes when weather, snow, visibility, or operational margins change.

Destination evidence directory

Every live destination, one comparable contract.

13 profiles have an official observed reference, 0 have commercial evidence only, and 21 retain an explicit representative gap.

DestinationSnow evidenceClimateJanFebMarAprMayJunJulAugSepOctNovDecPublic avalanche context
GreenlandGreenlandRepresentative monthly and interannual values remain unavailableTier F · data gappolarNo verified public bulletinNo verified public regional avalanche bulletin
Northern British ColumbiaCanada1,325 mm SWE median · 1,110–1,440 mm interquartile rangeTier B · observed referencemaritimeVerified public bulletinAvalanche Canada regional forecast map
IcelandIcelandRepresentative monthly and interannual values remain unavailableTier F · data gapmaritimeVerified public bulletinIcelandic Meteorological Office regional forecast
Tasman GlacierNew Zealand3.95 m published average · 2.58–5.32 m observed rangeTier B · observed referencemaritimeVerified public bulletinNZAA Aoraki/Mount Cook region
Val d’Aran, CataloniaSpainRepresentative monthly and interannual values remain unavailableTier F · data gaptransitionalVerified public bulletinCentre de Lauegi Val d’Aran bulletin
Gulmarg, KashmiriIndiaRepresentative monthly and interannual values remain unavailableTier F · data gapcontinentalVerified public bulletinDGRE district avalanche warning bulletin
Almaty, KazakhstanKazakhstanRepresentative monthly and interannual values remain unavailableTier F · data gapcontinentalOfficial weather or hazard source onlyKazhydromet weather and hazard warnings
Altai, KazakhstanKazakhstanRepresentative monthly and interannual values remain unavailableTier F · data gapcontinentalOfficial weather or hazard source onlyKazhydromet weather and hazard warnings
AlaskaUnited StatesRepresentative monthly and interannual values remain unavailableTier F · data gaptransitionalVerified public bulletinAlaska public forecast-center directory
Carpathian MountainsRomaniaRepresentative monthly and interannual values remain unavailableTier F · data gapcontinentalOfficial weather or hazard source onlyRomanian mountain weather and seasonal warnings
Methven, CanterburyNew Zealand2.40 m published average · 1.45–4.23 m observed rangeTier B · observed referencetransitionalVerified public bulletinNZAA Canterbury region forecast
Sun Valley, IdahoUnited States252 cm median · 179–329 cm interquartile rangeTier B · observed referencecontinentalVerified public bulletinSawtooth Avalanche Center
Santiago, Central AndesChileRepresentative monthly and interannual values remain unavailableTier F · data gapcontinentalOfficial weather or hazard source onlyDMC weather forecasts and warnings
Mount CookNew Zealand3.95 m published average · 2.58–5.32 m observed rangeTier B · observed referencemaritimeVerified public bulletinNZAA Aoraki/Mount Cook region
Svaneti, GeorgiaGeorgiaRepresentative monthly and interannual values remain unavailableTier F · data gaptransitionalOfficial weather or hazard source onlyGeorgia National Environmental Agency warnings
AntarcticaAntarcticaRepresentative monthly and interannual values remain unavailableTier F · data gappolarNo verified public bulletinNo public commercial avalanche bulletin
Troll Peninsula, IcelandIcelandRepresentative monthly and interannual values remain unavailableTier F · data gapmaritimeVerified public bulletinIcelandic Meteorological Office Northern Tröllaskagi forecast
Eastern British ColumbiaCanada746 mm SWE median · 602–870 mm interquartile rangeTier B · observed referencetransitionalVerified public bulletinAvalanche Canada regional forecast map
Karakol, KyrgyzstanKyrgyzstanRepresentative monthly and interannual values remain unavailableTier F · data gapcontinentalOfficial weather or hazard source onlyKyrgyzHydromet weather and hazard information
Interior British ColumbiaCanada1,910 mm SWE median · 1,418–2,169 mm interquartile rangeTier B · observed referencetransitionalVerified public bulletinAvalanche Canada regional forecast map
Chugach Mountains, AlaskaUnited States866 cm median · 690–952 cm interquartile rangeTier B · observed referencemaritimeVerified public bulletinChugach Avalanche Center and Alaska forecast directory
KamchatkaRussiaRepresentative monthly and interannual values remain unavailableTier F · data gapmaritimeOfficial weather or hazard source onlyRoshydromet forecasts and warnings
Eastern TurkeyTurkeyRepresentative monthly and interannual values remain unavailableTier F · data gapcontinentalOfficial weather or hazard source onlyMGM MeteoUYARI avalanche and weather warnings
Lake BaikalRussiaRepresentative monthly and interannual values remain unavailableTier F · data gapcontinentalOfficial weather or hazard source onlyRoshydromet forecasts and warnings
Patagonia, South AndesChile and ArgentinaRepresentative monthly and interannual values remain unavailableTier F · data gapmaritimeOfficial weather or hazard source onlyChile DMC and Argentina SMN weather warnings
Bishkek, KyrgyzstanKyrgyzstanRepresentative monthly and interannual values remain unavailableTier F · data gapcontinentalOfficial weather or hazard source onlyKyrgyzHydromet weather and hazard information
CaucasusGeorgiaRepresentative monthly and interannual values remain unavailableTier F · data gaptransitionalOfficial weather or hazard source onlyGeorgia National Environmental Agency warnings
RiksgränsenSweden77 cm median peak · 55–102 cm interquartile rangeTier B · observed referencemaritimeVerified public bulletinSwedish EPA Abisko/Riksgränsfjällen bulletin
Tordrillo Mountains, AlaskaUnited States237 cm median · 200–273 cm interquartile rangeTier B · observed referencetransitionalNo verified public bulletinNo verified staffed public forecast for the full tenure
Manali, Himachal PradeshIndiaRepresentative monthly and interannual values remain unavailableTier F · data gapcontinentalVerified public bulletinDGRE district avalanche warning bulletin
Queenstown and WānakaNew Zealand3.10 m published average · 1.84–5.53 m observed rangeTier B · observed referencetransitionalVerified public bulletinNZAA Wānaka and Wakatipu regions
MendozaArgentinaRepresentative monthly and interannual values remain unavailableTier F · data gapcontinentalOfficial weather or hazard source onlyArgentina SMN forecasts and early warnings
Bella Coola, British ColumbiaCanada820 mm SWE median · 659–1,034 mm interquartile rangeTier B · observed referencemaritimeVerified public bulletinAvalanche Canada regional forecast map
Snowbird, UtahUnited States1,248 cm median · 1,025–1,438 cm interquartile rangeTier B · observed referencecontinentalVerified public bulletinUtah Avalanche Center Salt Lake forecast

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