Free · open · no server · no key · no rate limit

Windgrams

Soaring forecasts for paragliding and hang-gliding launches — six weather models, rebuilt every run into the time-height picture a pilot actually reads before flying, published as plain JSON for anyone to render.

What this is

A forecast pipeline with no infrastructure to fail

A GitHub Actions workflow checks Environment and Climate Change Canada and NOAA every fifteen minutes. When a model publishes a new run, it derives boundary-layer top, cloud base, thermal strength, and usable lift for every catalogued launch, and commits the result. That's the entire production system.

“No server, no database, no API keys, no bill.”— docs/engineering-the-pipeline.md

This site fetches that same published JSON straight from GitHub, in your browser, right now. There's nothing in between — no API of ours to rate-limit you, go down, or change its mind.

The roster

Six models, one shape

Each speaks a different resolution and a different horizon, but every one ends at the same profile: hourly surface conditions, nine pressure levels, and the soaring numbers derived from them — so switching models never means switching how to read the chart.

HRDPS 2.5 kmBaseline

The always-there baseline. 2.5 km still smooths mountain terrain — the model's ground sits below the real launch; see the elevation note on the chart.

HRDPS 1 kmExperimental

Experimental. BC / western Alberta only, and the feed goes dark occasionally — treat HRDPS 2.5 km as the baseline and this as a sharper second look when it's up.

RDPS 10 kmTrend, not truth

10 km smears terrain — trend, not truth. Useful for "is the weekend worth watching" well before HRDPS can answer.

GDPS 15 kmTrend, not truth

Global, 15 km, out to 10 days — trend, not truth. Precipitation is a 3-hour total per column, matching its step.

HRRR 3 kmBaseline

A second convection-resolving opinion, built on the synoptic (00/06/12/18Z) cycles. Its domain reaches well into southern BC.

GFS 25 kmTrend, not truth

Global, out to 16 days — trend, not truth, and only useful that far out as a coin-flip check. Precipitation is a 3-hour total per column.

“The model's ground is not your ground.”— docs/how-a-windgram-is-computed.md

Every profile carries both numbers — the model's elevation and the real one — so the chart can show the gap instead of hiding it. That's the whole house style: say what the model can't see.

Open the chartView the source