Vector Field Map
Signature
sp.vector_field_map(title, lats=None, lons=None, u=None, v=None, *, variant="arrows", color_low=None, color_high=None, **kwargs) -> Chart
Aliases: sp.vector_field_map, sp.vectorfieldmap, sp.vector_field_map_chart, sp.wind_map, sp.quiver_map, sp.geo_vector_field, sp.build_vector_field_map
Description
sp.vector_field_map() draws a direction-and-magnitude sample at each lats/lons point from its u (east-west) and v (north-south) components — wind, ocean currents, anything that has a direction as well as a size at a location. Magnitude scales both length and color from color_low to color_high; direction accounts for the map’s own north-is-up orientation, not raw pixel angles.
Variants
Parameters
Returns
Chart — object with .html property and .show() method.
The default, and the classic weather-map quiver: one shaft-and-arrowhead per sample, pointing the true u/v direction, length and color both scaled by magnitude so the strongest vectors are immediately the most visible ones.
True flow integration, not a static hint field: a grid of seed points is traced forward through the inverse-distance-weighted u/v field step by step, each curving path following the local direction it’s actually moving through until the flow dies out or it leaves the sampled region — the same idea a real streamline or particle-flow visualization uses, not a decorative curve.
Real WMO station-model glyphs, not decorated arrows: the shaft points in the direction the wind blows from, and speed is read off by counting symbols stacked along it — a triangular pennant for every 50 knots, a full barb for every 10, a half barb for the last 5, rounded to the nearest 5kt exactly like a real synoptic chart. A calm station (under 2.5kt) draws the standard open-circle calm symbol instead of a shaft. Meteorology’s own encoding, applied directly to u/v.