Real radiosonde launches · never model data
Observed soundings
Latest and previous balloon launch for Western Canada and nearby US sites. Launches are normally 00Z and 12Z, and data arrives over the following 1–3 hours. A late or missing launch is shown as late or missing, never filled in. Times are UTC.
How to use this page · tap any ? for a full explanation
- Pick a station from the menu or the All stations table. Choose the nearest one and the one upstream (usually to the west).
- Read the tephigram from the bottom up: red-orange = temperature, blue = dewpoint. Where they touch, the air is saturated (cloud, fog, icing); a bend to the right is an inversion.
- Find the 0 °C line (bold orange). Crossing it more than once means a warm layer aloft: freezing rain or ice pellets.
- The black dashed parcel shows rising surface air. Orange area = CAPE (fuel for showers and storms), blue = CIN (the lid).
- ❄ Winter (top right of each card) shades melting / refreezing energy, icing bands, the snow-growth zone and turbulence (Ri) bars. Zoom with + / − or the mouse wheel.
- The values grid gives freezing levels, moist layers, icing, wind shear (against the MANAIR guide), stability indices and the tropopause. Each label has a ?.
- Compare Latest with Previous: what changed in 12 hours is often the forecast.
- Words are explained in the glossary at the bottom.
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All stations
| Station | Latest launch | Status | Previous launch |
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Moist layers are where T − Td ≤ 3 °C: a first look at cloud and icing layers, not observed cloud. Heights are feet above ground unless marked ASL. In the level table, grey rows are interpolated between reported levels. Canada: Data Source: Environment and Climate Change Canada (TEMP and PILOT bulletins). Annette Island and Yakutat: NWS TEMP part A through ECCC, standard levels only. Lower 48: Iowa Environmental Mesonet.
Glossary: words used on this page
See the site glossary.