Typical operating window
December–MarchCold-season precipitation usually builds usable coverage from late November through early winter.Verified planning context
Snow, weather and avalanche context
Historical patterns help you compare trips. They do not predict your week or replace the operator's daily decisions.
Strongest comparable snow evidence
598 mm SWE median · 526–637 mm interquartile rangeShymbulak reference ERA5-Land grid cellTier C · modelled estimate · low confidenceSnow character
continentalCold continental powder can persist in shade. Wind slabs and persistent weak layers require close professional monitoring.Public avalanche information
Kazhydromet weather and hazard warningsNo verified public run-scale avalanche bulletin was identified. Operator assessment is essential.Weather and flight context
Continental cold combines with terrain-enhanced snowfall in the Trans-Ili Alatau.
- Valley inversion and haze
- High ridgeline wind
- Cold-soaked aircraft operations
Meteorological reference area
Almaty and northern Tien Shan catalogue locations
- Includes
- Northern Tien Shan evidence linked to Almaty programs.
- Excludes
- Altai and Kyrgyz Tien Shan profiles.
- Elevation
- No verified operator-terrain elevation band is public. Each evidence value retains its site elevation.
Evidence pack
Measurements, claims and gaps stay separate.
Tier CModelled snowfall water equivalent598 mm SWE median · 526–637 mm interquartile range
- Site
- Shymbulak reference ERA5-Land grid cell · 43.1000, 77.1000 · 3.7 km from Shymbulak reference reference point
- Period
- Calendar years 1991–2020
- Completeness
- 360 monthly means; all 30 calendar years contain 12 values.
- Method
- ERA5-Land monthly mean daily snowfall accumulation was multiplied by calendar days and 1,000, then summed by calendar year.
- Limitation
- This reference area supports evidence discovery and comparison. It is not an operating-area or tenure boundary. This unadjusted 0.1° reanalysis grid cell is not an observation, snow depth, or terrain-wide total. Grid elevation and wind redistribution can cause substantial local bias.
- ERA5-Land monthly averaged data from 1950 to presentCopernicus Climate Change Service · accessed 2026-08-26
Monthly evidence
Each cell keeps its measurement type and unit. Reanalysis water equivalent is not snow depth. Text-only cells preserve a representative data gap.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 34.9 mm SWE | 49.7 mm SWE | 73.3 mm SWE | 97.8 mm SWE | 63.5 mm SWE | 18.6 mm SWE | 2.5 mm SWE | 7 mm SWE | 40.6 mm SWE | 71.3 mm SWE | 59.7 mm SWE | 44 mm SWE |
Commercial operator assessment
Operator assessment process not independently verifiedThe operator must assess current snow, avalanche terrain, weather, aircraft limits, and rescue options. No private operational plan is inferred.
Sources and evidence notes
- WMO Climatological NormalsWorld Meteorological Organization · accessed 2026-08-25
- ERA5-Land hourly data from 1950 to presentCopernicus Climate Change Service · accessed 2026-08-25
- Weather and warningsKazhydromet · accessed 2026-08-25
- Published operator and trip inventoryHeliski International editorial team · accessed 2026-08-25
- ERA5-Land monthly averaged data from 1950 to presentCopernicus Climate Change Service · accessed 2026-08-26