Section 5. Aircraft Rescue and Fire Fighting Communications 6-5-1. Discrete Emergency Frequency 6-5-2. Radio Call Signs 6-5-3. ARFF Emergency Hand Signals . 6-5-1 6-5-1 6-5-1 Chapter 7. Safety of Flight Section 1. Meteorology 7-1-1. National Weather Service Aviation Weather Service Program 7-1-2. FAA Weather Services . 7-1-3. Use of Aviation Weather Products . 7-1-4. Graphical Forecasts for Aviation (GFA) 7-1-5. Preflight Briefing 7-1-6. Inflight Aviation Weather Advisories . 7-1-7. Categorical Outlooks 7-1-8. Telephone Information Briefing Service (TIBS) (Alaska Only) . 7-1-9. Transcribed Weather Broadcast (TWEB) (Alaska Only) . 7-1-10. Inflight Weather Broadcasts . 7-1-11. Flight Information Services (FIS) . 7-1-12. Weather Observing Programs 7-1-13. Weather Radar Services . 7-1-14. ATC Inflight Weather Avoidance Assistance 7-1-15. Runway Visual Range (RVR) 7-1-16. Reporting of Cloud Heights 7-1-17. Reporting Prevailing Visibility 7-1-18. Estimating Intensity of Rain and Ice Pellets 7-1-19. Estimating Intensity of Snow or Drizzle (Based on Visibility) 7-1-20. Pilot Weather Reports (PIREPs) 7-1-21. PIREPs Relating to Airframe Icing 7-1-22. Definitions of Inflight Icing Terms 7-1-23. PIREPs Relating to Turbulence . 7-1-24. Wind Shear PIREPs 7-1-25. Clear Air Turbulence (CAT) PIREPs 7-1-26. Microbursts . 7-1-27. PIREPs Relating to Volcanic Ash Activity 7-1-28. Thunderstorms 7-1-29. Thunderstorm Flying . 7-1-30. Key to Aerodrome Forecast (TAF) and Aviation Routine Weather Report (METAR) 7-1-31. International Civil Aviation Organization (ICAO) Weather Formats . 7-1-1 7-1-2 7-1-2 7-1-5 7-1-7 7-1-9 7-1-16 7-1-17 7-1-17 7-1-17 7-1-20 7-1-24 7-1-32 7-1-36 7-1-38 7-1-40 7-1-40 7-1-40 7-1-41 7-1-41 7-1-42 7-1-43 7-1-45 7-1-46 7-1-46 7-1-46 7-1-57 7-1-57 7-1-58 7-1-60 7-1-62 Section 2. Altimeter Setting Procedures General Procedures . Altimeter Errors High Barometric Pressure Low Barometric Pressure . Table of Contents 7-2-1 7-2-1 7-2-3 7-2-4 7-2-4