Maidenhead grid module converts grid squares to lat/lon coordinates.
Submission form validates grids, bands, modes, and email, computes
positions and distance, then triggers the weather/HRRR/terrain
processing pipeline via Oban.
Fetch elevation data along the path between two stations via the
Open-Meteo Elevation API (with Open-Topo-Data fallback), compute
Fresnel zone clearance, earth bulge, and knife-edge diffraction loss,
and store the results per QSO.
- terrain_profiles table with migration and TerrainProfile schema
- ElevationClient with batched API calls and fallback
- TerrainAnalysis with Fresnel/diffraction physics (ITU-R P.526-15)
- TerrainProfileWorker on Oban :terrain queue
- QsoWeatherEnqueueWorker enqueues terrain jobs automatically
- QSO show page displays verdict badge and collapsible elevation table
- Reorder show page: terrain, soundings, solar, HRRR, surface obs
- Fix Dockerfile wgrib2 build (add cmake dependency)
HRRR provides hourly 3km-resolution atmospheric profiles, filling the
temporal gaps (12-hourly soundings) and spatial gaps (only 9 sounding
stations) in our current weather data.
- Add hrrr_profiles table and hrrr_queued flag on QSOs
- HrrrClient fetches GRIB2 data via HTTP Range requests + wgrib2
- HrrrFetchWorker derives refractivity/ducting params via SoundingParams
- QsoWeatherEnqueueWorker now also enqueues HRRR jobs
- QSO show page displays HRRR section with collapsible profile
- Dockerfile builds wgrib2 from source for production
Oban cron worker runs every 4 hours, finds QSOs without weather data,
discovers nearby ASOS/sounding stations, and enqueues WeatherFetchWorker
jobs. Migrations run automatically on app start in production.
Instead of fetching inline with Task.async_stream (which hammered IEM
with concurrent requests), the import script now just checks what data
is missing and enqueues WeatherFetchWorker jobs. Oban handles all HTTP
with concurrency 3 and automatic backoff on failures.
IEM was returning 503s under 10 concurrent workers. Three fixes:
- Req transient retry with exponential backoff on IEM requests
- WeatherFetchWorker Oban job retries failed ASOS/RAOB fetches 2-3h later
with random jitter to avoid thundering herd
- Import script concurrency reduced 10→5, weather queue capped at 3
Store surface observations (ASOS) and upper-air soundings (RAOB) alongside
QSOs for atmospheric propagation correlation. Three new tables: weather_stations,
surface_observations, and soundings with JSONB profiles and pre-computed derived
parameters (refractivity, gradients, duct detection, stability indices).
Includes IEM API client for historical data import and import script seeded
with 95 ASOS + 9 sounding stations from PropCast coverage area.
