Can deep seasonal snow change the interpretation of a low-height wind sensor?

The short answer

Deep seasonal snow can change the surface and exposure around a low-height sensor. It may also coincide with other measurement problems, so a winter record needs an environmental context. The response is to document the change and assess its relevance, not to apply an invented universal snow correction to every wind value.

Record what physically changed

Keep dated site photographs, approximate snow-depth observations where available and notes on drifting near the instrument. Distinguish the fixed sensor position from the changing surface below it. Snow banks can alter local exposure even when the mast has not moved.

Record access restrictions and any changes made during a visit. If a boom is raised or an instrument is repositioned, that becomes a separate configuration change with its own effective date.

Separate exposure from sensor condition

Review whether suspect winter readings relate to changed flow, sensor icing, damaged equipment or missing data. These mechanisms require different treatments. A large snow depth does not prove that every winter observation is invalid, and an apparently plausible record does not prove the sensor remained unaffected.

Compare concurrent measurements and environmental records where available. Keep the original data and apply explicit quality flags rather than silently modifying the series until the annual average looks reasonable.

Assess the transfer to turbine height

Ask the assessor whether the seasonal measurement geometry still supports the intended hub-height interpretation. A low sensor affected by local drifting may require a different uncertainty treatment from an exposed higher measurement. Do not extrapolate a simple depth difference into an energy correction without a defensible model.

The campaign handover should identify affected dates, known surface conditions, instrument changes and the chosen analysis response. If winter resource is central to a remote site's service needs, resolve material uncertainty before relying on that period for equipment sizing or fuel-displacement estimates.