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StormVeil 0.3: MOS support and wind-rose panel

2026-04-02 · Jakub Nowak

StormVeil 0.3 adds MOS (Model Output Statistics) forecast support and a wind-rose panel.

MOS forecasts

METAR gives you current conditions; TAF gives you a 30-hour forecast in coded form. MOS gives you point forecasts from the GFS model at specific station sites, including sky cover, precipitation probability, and ceiling height broken out by 3-hour intervals. It's particularly useful for planning trips 24-72 hours out when TAF coverage is thin.

StormVeil fetches MOS from the NOAA MDL endpoint, decodes the fixed-width text format, and renders it as a timeline panel alongside METAR and TAF.

Wind rose

The new --rose flag renders a text-art wind rose from the last 24 hours of METAR observations at a station. It's coarser than a proper meteorological wind rose, but useful for quickly checking prevailing direction before a ridge hike.

The rose is drawn using Unicode block characters. On terminals that render them well it looks decent; on terminals that don't it falls back to ASCII.


Also: Writing a METAR decoder in Python: lessons from the spec