Learn where X-Plane gets real-world weather data, how METARs and forecast models are blended, and why live conditions may differ or stop updating.
X-Plane gets real-world weather through Laminar Research’s online weather service. That service processes aviation observations, including METARs, together with numerical forecast and upper-air data, then supplies a weather package to the simulator. NOAA has historically provided key upstream products, but X-Plane does not depend on one public weather webpage.
The X-Plane real-weather data chain
NOAA products have historically been important upstream inputs, while Laminar’s servers are the online service that X-Plane itself normally contacts.
This distinction explains why sources sometimes appear to conflict. Saying that weather comes from NOAA describes the meteorological data provider or distributor; saying that it comes from Laminar describes how the simulator receives its prepared data.
- Weather observations are issued. Airport stations and national weather services publish reports such as METARs and SPECIs, which are exchanged through international aviation networks.
- Forecast centres produce gridded data. Numerical weather models describe winds, temperature, pressure and other atmospheric properties between reporting stations and at altitude.
- Laminar’s service prepares the data. Its backend collects, processes and caches the information required by X-Plane’s stock real-weather system.
- X-Plane downloads and renders it. The simulator converts those inputs into surface conditions, winds aloft, visibility, clouds and a continuous three-dimensional atmosphere.
NOAA does not physically measure every observation in this chain. Many METARs originate at airports outside the United States and are then distributed through shared aviation-weather systems. Laminar can also change its backend processing or upstream feeds without adding a new source selector to X-Plane.
Does X-Plane use METARs or forecast models?
X-Plane uses both station observations and broader model data because neither source can create convincing worldwide weather on its own.
| Input | What it contributes | Main limitation |
|---|---|---|
| METAR and SPECI observations | Surface wind, visibility, temperature, dew point, pressure, present weather and reported cloud layers near an airport | Each report represents one station and one observation time |
| Gridded forecast and upper-air data | Winds and temperatures aloft, regional pressure patterns and conditions between airports | Modelled values will not reproduce every local variation |
| X-Plane’s weather engine | Blending, transitions, cloud geometry and the atmosphere experienced by the aircraft | The result is an interpretation of the inputs, not a literal picture of a weather report |
METARs anchor local conditions, but they leave large gaps over oceans, remote areas and cruise levels. Forecast-model data fills those gaps and gives the simulator a coherent regional atmosphere rather than separate bubbles around reporting airports.
When comparing an airport report with the simulator, use our practical guide to decoding METAR wind, visibility, pressure and cloud groups. Misreading variable wind, cloud height or visibility units can make correct simulator weather appear wrong.
Why doesn’t X-Plane match the latest METAR exactly?
A live X-Plane scene can legitimately differ from the latest METAR because the simulator is blending a continuous atmosphere from reports issued at different places and times.
- Different update times: a new METAR or SPECI may have been issued after X-Plane downloaded its weather package.
- Point observation versus aircraft position: the METAR describes conditions at the station, not necessarily several miles away or thousands of feet above it.
- Model blending: station observations may be reconciled with neighbouring reports and gridded atmospheric data instead of being imposed as hard-edged zones.
- Cloud interpretation: a METAR reports operationally significant cloud amount and base, not the exact shape, position or depth of every cloud. X-Plane must generate that geometry itself.
- Sparse observations: model data carries more weight where few airports report weather.
- Download delay or failure: depending on the version and session, X-Plane may retain older conditions when it cannot obtain a fresh package.
- Third-party add-ons: a weather injector can replace Laminar’s feed, while a cloud or environment add-on may change only how the same data looks.
A small difference in wind, cloud coverage or visibility is not proof that real weather has failed. A persistent mismatch in surface wind and QNH at a frequently reporting airport is a better reason to investigate.
Does changing the simulator time load historical weather?
No: changing the clock in X-Plane does not turn the live-weather service into a historical weather archive.
Real weather remains tied to the live data available from the service, even when the simulator is set to another hour. For the resulting daylight, cloud and update behaviour, see our explanation of how X-Plane 12 real weather reacts when simulator time changes. Use manual weather when recreating past or hypothetical conditions.
X-Plane 11 and X-Plane 12 weather-source differences
Both X-Plane 11 and X-Plane 12 obtain stock live weather online from Laminar’s service, but they process and depict that information differently.
X-Plane 11 is commonly documented in terms of downloaded METAR and GRIB data, including files such as METAR.rwx. X-Plane 12 has a substantially revised atmospheric and cloud system, so older instructions involving those files do not describe the whole X-Plane 12 weather pipeline.
The source answer is therefore not that X-Plane 11 uses NOAA while X-Plane 12 uses Laminar. NOAA can be an upstream supplier of weather products in both cases, while Laminar operates the delivery service used by the simulator. The visible differences largely come from each version’s weather engine, blending and rendering.
How can I tell whether X-Plane real weather is updating?
The most reliable test is to run the stock real-weather system without injectors, confirm a successful download and compare the basic surface values at a reporting airport.
- Choose the stock real-weather mode. Check that weather is not set to a manual preset or customised conditions.
- Disable weather-related add-ons. Test without injectors first; an environment add-on may also need to be disabled if the data seems correct but the clouds look wrong.
- Check X-Plane’s network access. A firewall, security tool, DNS problem or VPN can block the weather service even when ordinary web browsing works.
- Verify the computer clock. A badly incorrect system date or time can interfere with online connections and make update ages misleading.
- Request fresh weather after restoring the connection. Re-select real weather or restart X-Plane rather than assuming a stale session will immediately recover.
- Inspect
Log.txt. After closing the simulator, open this file in the main X-Plane folder and look for weather-download or network errors. Exact wording varies between versions. - Compare the right values. At an airport with a recent report, check surface wind, QNH, visibility and cloud base. Do not expect identical cloud shapes or an exact match to winds aloft.
If the log shows a successful weather download and the principal surface values broadly agree with the airport report, differences in cloud placement or upper-level conditions usually reflect X-Plane’s model blending and weather rendering rather than a different data source.