CFI Instrument Practical Test Standards, FAA-S-8081-9B, June 2001

III. Preflight Preparation

A. Weather Information

2. Weather reports and forecasts
    c. Surface analysis, weather depiction and radar summary charts
      1) Surface analysis chart
        a) Depicts weather data actually observed in the contiguous 48 states at the time stated on the chart
        b) Elements
          i) Pressure systems
          ii) Fronts
          iii) Isobars
          iv) Station models
          • Sky cover and cloud types
          • Wind
          • Temperature and dew point temperature
          • Sea level pressure and 3-hour change
          • Present weather
          • 6-hour precipitation amount
          c) Computer-generated, with frontal analysis by the Hydrometeorological Prediction Center (HPC)
          d) Transmitted every 3 hours
          e) Provides ready means of locating pressure systems and fronts present at chart time
          f) Surface analysis type charts available on the internet
      2) Weather depiction chart
        a) Computer-prepared, with frontal analysis by a forecaster, from METARs
        b) Depicts broad overview of weather conditions observed at chart valid time; e.g., areas of VFR, MVFR and IFR conditions
        c) Issued each day first at 0100Z, and transimitted every 3 hours thereafter
        d) Data plotted from the latest manual and automated (denoted by ]) station observations
          i) Total sky cover
          ii) Cloud height
          iii) Weather and obstructions to visibility
        e) Analysys
          i) IFR = ceiling < 1,000 FT and/or visibility < 3 SM
          ii) MVFR = ceiling 1,000 to 3,000 FT and/or visibility 3 to 5 SM
          iii) VFR = ceiling > 3,000 FT and visibility > 5 SM
        f) Good chart to study first
          i) Gives bird's-eye view of areas of VFR and IFR weather
          ii) Update with current METARs
        g) Weather depiction type charts online
      3) Radar summary chart
        a) Computer-generated graphical display of SDs
        b) Displays and describes areas of precipitation and severe weater watches
        c) Available hourly at H + 35 minutes (35 minutes past the hours)
        d) Elements
          i) Precipitation type
          ii) Intensity
          iii) Configuration and coverage
          v) Cell movement
          vi) Severe weather watch areas
        e) Use preflight to identify general areas and movement of precipitation and/or thunderstorms
        f) Update airborne (FSS Flight Watch)
        g) Radar summary type charts online

Greg Gordon MD, CFII