pick a place, then load a profile ·
License: custom, not open-source. Using the app is permitted; modifying, redistributing, or publishing a derivative version needs the copyright holder's prior written permission and must keep attribution.
StueveCast draws Stüve, Emagram and Skew-T diagrams from numerical weather model profiles for any place and forecast hour, using the diagram and the fourteen analytics fields of the S2 Radiosonde Sounding Diagram tool. Left panel: place (map crosshair, search, ◎ position, ★ saved places — ☆ in the place card saves the crosshair position, the list opens with ★ or by focusing the empty search field), valid time and the model list; ‹ hides the panel. Chips above the chart list every model that covers the place and hour: tap to add, × to remove, tap a comparison chip to make it primary. The primary model drives the analytics; the others are dashed comparison curves.
Reading the chart: dots mark the real model levels; everything in between is interpolated. The green line is the model ground, which can differ from the real terrain. Drag the amber handle between the temperature plot and the wind-speed panel to give either one more room (double-tap resets). On a touch screen press and hold on the chart to read values, or lock the ✛ mode; pinch to zoom the altitude band, or use the two sliders on the left of the chart. On phones the profile opens zoomed to the lower ~10 km; ⟲ shows the full column.
Time: one slider covers every hour up to the longest model horizon (16 days); day chips jump, ‹ › step, ▶ animates. Every manual time change clears the model selection: the list re-sorts (models covering the hour first, finest grid on top) and the chips above the chart offer the models for that hour — pick anew. ▶ playback keeps the selection; a model whose horizon ends simply drops out of the chart. Run times are estimated from each model's cycle.
avg.: with two or three models shown, the avg. chip draws their weighted mean as the primary curve (weight = 1/√grid km ÷ (1 + run age h / 6), normalised per level) and moves the individual models to dashed comparison curves; the analytics then describe the blend.
Offline: the app shell and the last fetched profiles are cached, so the slider keeps working without a connection.
Data: Open-Meteo (CC BY 4.0) with pressure-level output of DWD ICON, Météo-France AROME/ARPEGE, NOAA GFS/HRRR, ECMWF IFS/AIFS, UK Met Office, ECCC GEM and JMA. MeteoSwiss ICON-CH1/CH2 have no pressure levels on Open-Meteo yet and are planned for a later version. Map tiles by OpenStreetMap and OpenTopoMap, place search by Open-Meteo geocoding, place names by Nominatim. Includes Leaflet (BSD-2-Clause) and qrcodejs (MIT).