Weather Layers: METAR, TAF, SIGMET, PIREPs
What each weather layer in AeroCopilot represents, who issues it, and how often it refreshes — METAR, TAF, SIGMET, G-AIRMET, PIREPs, winds aloft, and more.
Weather layers in AeroCopilot are sourced directly from the National Weather Service (NWS) and NOAA via the Aviation Weather Center API. Nothing is paraphrased and nothing is invented — the layer you see is the layer the issuing agency published, parsed and rendered. This page documents what each layer represents and how often it updates.
Observations
METAR — Aviation Routine Weather Reports
Source: NWS · Refresh: every 5 minutes · Coverage: ~5,000+ US reporting stations.
Hourly observations encoding wind, visibility, ceiling, temperature, dewpoint, altimeter, and remarks. AeroCopilot ingests the raw METAR text plus parsed fields, and powers the airport directory current-conditions block, the briefing tool, and the go/no-go assistant. Upstream: aviationweather.gov/data/api/.
PIREP — Pilot Reports
Source: NWS · Refresh: every 15 minutes.
Pilot-reported observations including turbulence, icing, sky conditions, and ride quality. Decoded with location, altitude, aircraft type, and observation text. On a planned route, PIREPs are filtered to a 25 NM corridor over the last 6 hours, with URGENT UUA callouts and turbulence/icing badges.
Forecasts
TAF — Terminal Aerodrome Forecasts
Source: NWS · Refresh: issued every 6 hours, polled every 15 minutes · Coverage: ~700 US TAF sites.
24–30 hour terminal forecasts with FM, BECMG, and TEMPO change groups parsed out. Drives the AI departure/arrival window analysis and the alternate-selection logic.
Winds and Temperatures Aloft
Source: NWS · Refresh: every 6 hours.
Forecast winds and temperatures at standard pressure altitudes from 3,000 to 53,000 feet, decoded for FAA forecast points. Used by the cruise altitude optimizer and fuel-reserve calculator.
MOS — Model Output Statistics
Source: NWS · Refresh: every 6 hours.
GFS-MOS hour-by-hour statistical forecasts at major airports out to 84 hours. Surfaced through the AI Copilot when you need granularity finer than TAF intervals.
Hazards
SIGMET — Significant Meteorological Information
Source: NWS · Refresh: issued as needed, polled every 15 minutes.
Hazard advisories for severe icing, severe turbulence, dust storms, sandstorms, volcanic ash, and convective activity. Stored as geometry polygons with altitude bands and validity windows; rendered as a map overlay and fed to the AI hazard summary.
G-AIRMET — Graphical Airmen Meteorological Information
Source: NWS · Refresh: every 6 hours.
Polygons covering moderate turbulence, icing, IFR conditions, mountain obscuration, and surface winds. Map overlay plus AI references for less-than-severe but operationally relevant hazards.
CIP/FIP Icing
Source: NWS · Refresh: hourly.
Current Icing Product (CIP) and Forecast Icing Product (FIP) severity grids by altitude and forecast hour. Feeds the AI icing-risk advisory with FIKI-aware framing.
GTG Turbulence
Source: NWS · Refresh: hourly.
Graphical Turbulence Guidance — clear-air, mountain wave, and convective induced — by altitude and forecast hour. Used by the cruise altitude optimizer.
SPC Convective Outlook
Source: NOAA Storm Prediction Center · Refresh: every 6 hours.
Day 1–3 risk polygons (MRGL, SLGT, ENH, MDT, HIGH) for severe thunderstorms. Used in long-range planning warnings.
SPC Watches
Source: NOAA · Refresh: issued as needed, polled every 15 minutes.
Severe-thunderstorm and tornado watch boxes with category, expiration, and probability. Map overlay plus ground-stop guidance for affected airports.
CWA — Center Weather Advisories
Source: NWS · Refresh: issued as needed, polled every 15 minutes.
CWAs from CWSU meteorologists by ARTCC, referenced by the AI Copilot during enroute weather updates.
Other useful layers
- NWS Public Alerts (CAP) — every 5 minutes; high-severity alert banners.
- NWS Area Forecast Discussion — every 6 hours; long-form forecaster reasoning that the AI cites in multi-day briefings.
- Mountain Obscuration Forecast — G-AIRMET polygons every 6 hours; the AI warns when a route crosses obscured terrain.
- Space Weather (NOAA SWPC) — every 30 minutes; relevant for high-latitude and high-altitude operations.
- NHC Tropical Cyclones — every 6 hours during active systems.
Diff badges
When you reopen a briefing, AeroCopilot detects deltas (NEW / UPDATED / EXPIRED) on METAR, TAF, NOTAM, SIGMET, and TFR data since your last refresh and surfaces them in a top banner. Snapshots are persisted on the flight plan; the diff window debounces at 5 minutes.