Astro Cloud & Weather Forecasting
Astrospheric, Clear Outside, 7Timer!, Heavens-Above — clear-sky charts and pass forecasts.
The "is it worth setting up tonight?" tier — astronomy-specific weather forecasting that goes beyond "rain or shine" into transparency, seeing, jet stream, dew point, moon phase, and integrated airglow / sky-quality. Plus the satellite-pass forecasters that overlap heavily — see Satellite Tracking for ground-station-grade passes.
For all-sky cameras / cloud monitoring see Meteor & All-Sky Cameras; for light pollution sources see Light Pollution & Filters; for IoT-side weather sensors that integrate see Sub-GHz, 433 MHz & RTL_433 and MQTT for Home.
All-in-one astro forecasts
- ★ ★ Astrospheric — paid free tier + paid pro (~$30/yr). The 2026 default astro forecast for North America (and increasingly worldwide). Mobile + web. Cloud cover layers (transparency, seeing, jet stream), aurora kp, ISS / Starlink / Iridium passes, moon altitude/phase, observation logbook, custom locations. Integrates with N.I.N.A's "wait until conditions" plug-in. Pro tier ($30/yr) is well worth it for serious imagers.
- ★ Clear Outside (First Light Optics) — free, web + iOS/Android. UK-born, global coverage; 7-day cloud cover at 3 altitudes, transparency, seeing, ISS pass, moon phase. Free; clean. The OSS-spirit pick (closed but free, no ads).
- Astropheric (different site) — niche; less polished.
- Pinpoint Weather (Stellarium Mobile Plus) — paid; embedded in Stellarium Plus.
Free legacy / global
- ★ 7Timer! — free; the public underlying ECMWF forecast that powers many other apps (Clear Outside, Stellarium); the no-frills web view at 7timer.info gives you the same cloud / transparency / seeing predictions for any lat/lon. Free; data-only; no app polish.
- Meteoblue — paid pro; transparency + seeing forecasts well-regarded; free tier available.
- NOAA / ECMWF / GFS direct — free raw model data; what 7Timer!, Astrospheric, and Clear Outside ultimately consume.
Aurora-specific
- ★ NOAA Space Weather Prediction Center — free; the source-of-truth Kp / OVATION model. Live aurora oval map.
- ★ SpaceWeatherLive (web) — free; clean Kp, solar wind, X-ray flux dashboards.
- My Aurora Forecast (paid mobile app) — wraps NOAA + push alerts.
- Aurora Pro — paid iOS.
Satellite-pass forecasters
- ★ Heavens-Above — free, web + paid mobile. The classic visual satellite pass forecaster: ISS, Starlink, Iridium flares (sunset), Tiangong, Hubble, NORAD specials. Decades of community trust.
- N2YO.com — free web; satellite tracking and passes; less polished but live tracking is good.
- ISS Detector — free + paid Android/iOS; ISS, Iridium, brighter sats, push alerts.
- GoSatWatch — paid iOS / Mac.
- Stellarium / SkySafari — built-in satellite pass display from NORAD TLEs; see Planetariums.
For ham-radio satellite tracking and SatNOGS see Satellite Tracking.
Hardware-side weather
- ★ Personal weather station — Davis Vantage Vue / Vantage Pro 2, Ecowitt GW1000 / WS80 / WS90, Acurite Atlas. Many feed Weewx or Home Assistant over MQTT — see MQTT for Home.
- ★ Sky-quality meter — Unihedron SQM-LU / SQM-LE; or DIY TSL2591 + ESP32. Logs naked-eye limiting magnitude over time.
- Cloud sensor — Boltwood Cloud Sensor II (paid, ~$1500); DIY MLX90614 IR sky-temperature ESPHome (free) — see ESPHome / Tasmota.
- Rain detector — Hydreon RG-11 (paid); cheap optical rain sensors on ESPHome (free).
- ★ Roof-flap automation — observatory dome / roll-off-roof closes on cloud or rain; HA automations from Boltwood / Hydreon / cloud sensor.
Integrating into a session manager
- N.I.N.A "Ground Station" plug-in — push N.I.N.A status to MQTT; pull Astrospheric / Open-Meteo from MQTT into "wait for clear sky" gates.
- Ekos weather modules — INDI Weather Watcher driver pulls from local sensors / online forecast and parks the mount on threshold breach.
- AllSky → MQTT → HA → INDI — full closed-loop "park scope when sky clouds over" — see Meteor & All-Sky Cameras.
What's changing in 2024–2026
- Astrospheric pro adoption — hobby astrophotographers paying $30/yr for the seeing forecasts is now mainstream.
- Open-Meteo — newer free forecast API; growing adoption in OSS dashboards.
- AI cloud cover — Astrospheric and Clear Outside are quietly using ML for cloud now.
- Aurora forecasting got better — NOAA OVATION model substantially improved 2023–24.
License / pricing summary
- Free: 7Timer!, Clear Outside, Heavens-Above, NOAA SWPC, N2YO, raw NOAA / ECMWF.
- Free + paid pro (~$30/yr): Astrospheric, Meteoblue, Stellarium Plus.
- Paid mobile (~$5–20): My Aurora, Aurora Pro, ISS Detector premium.
- Hardware: $50–$1500 depending on sensor tier.
Pick this if…
- Default astro forecast, North America: Astrospheric (Pro recommended).
- Default astro forecast, free / global: Clear Outside.
- Aurora-only: NOAA SWPC + SpaceWeatherLive.
- Satellite passes: Heavens-Above (web) or built into Stellarium.
- Local sensor → automation: Ecowitt + ESPHome + HA.
- Observatory roof safety: Boltwood + HA + N.I.N.A "Safety Monitor" plug-in.