HsSignificant wave height. Average of the highest third of waves.
Max HsHighest significant wave height expected in the selected forecast window.
SwellLonger-period sea travelling in from another weather system.
WindSustained wind near sea level, shown in your chosen wind unit.
GustShort stronger bursts above sustained wind.
DirDirection the wind or sea is coming from, in magnetic degrees where available.
VisVisibility. Low values can mean fog, haar, heavy rain or low cloud risk.
PressureAir pressure in millibars. Falling pressure often means worsening weather.
Cert file names
Naming rule used when cert files are uploaded to private cloud storage
Units
Wind
Sustained wind & gust, shown at 10m
About wind height
Wind & gust are shown at 10m — the standard forecast height used by the Met Office, operators and other weather apps, so CHOPPERS matches what you see elsewhere. Offshore decks sit much higher, where wind runs stronger, so always follow your operator’s own deck readings before flying.
Wave height
Hs, swell and forecast sea state
Distance
Routes, range and visibility preference
Temperature
Briefing temperature display
Account & Legal
Account
Sign-in, subscription management and data export will be added before paid launch