11-1.     Introduction

11-2.     Precipitation

11-3.     Obscurations

11-4.     Other Phenomena

11-5.     Qualifiers

11-6.     Order for Reporting Multiple Types of Weather and Obscurations

Figure 11-1.     Present Weather

11-7.     Rules for Phenomena Not Occurring at the Point of Observation

11-8.     Reporting and Documenting Precipitation

11-9.     Beginning and/or Ending of Precipitation (NA LAWRS)

11-10.   Determining and Reporting the Type of Precipitation

11-11.   Determining the Character of Precipitation

11-12.   Precipitation Intensity

Figure 11-2.     Estimating Intensity of Rain

Figure 11-3.     Estimating Intensity of Ice Pellets

Figure 11-4.     Intensity of Rain or Ice Pellets Based on Rate of Fall

Figure 11-5.     Intensity of Snow or Drizzle Based on Visibility

Figure 11-6.     Precipitation Intensity Symbols

11-13.   Intensity of Snow, Snow Pellets, Snow Grains, Drizzle and Freezing Drizzle

11-14.   Reporting Freezing Precipitation

11-15.   Beginning and/or Ending of Freezing Precipitation

11-16.   Intensity of Freezing Precipitation

11-17.   Reporting Ice Pellets

11-18.   Beginning and/or Ending of Ice Pellets (NA LAWRS)

11-19.   Intensity of Ice Pellets

11-20.   Reporting Precipitation Amounts (NA LAWRS)

11-21.   Priority of Gauges (NA LAWRS)

Figure 11-7.     Units of Measure for Precipitation 104

11-22.   Stick Measurement of Liquid Precipitation (NA LAWRS)

11-23.   Determining Water Equivalent of Solid Precipitation by Stick Measurement
              (NA LAWRS)

11-24.   Determining Water Equivalent of Solid Precipitation by Weighing (NA LAWRS)

11-25.   Estimating the Water Equivalent of Snow (NA LAWRS)

Figure 11-8.     New Snowfall to Estimated Meltwater Conversion Table

11-26.   Determination of 6-Hour Accumulation of Precipitation (NA LAWRS)

11-27.   Depth Measurement of Solid Forms (NA LAWRS)

11-28.   Snowfall within Specified Periods (NA LAWRS)

SECTION 3.   OBSERVING AND REPORTING TORNADOES, WATERSPOUTS,
                         AND FUNNEL CLOUDS

11-29.   Tornado, Waterspout, or Funnel Cloud

11-30.   Reporting Thunderstorms

11-31.   Beginning and/or Ending of a Thunderstorm

11-32.   Reporting Hail

11-33.   Beginning and/or Ending of Hail (NA LAWRS)

11-34.   Reporting Lightning

Figure 11-9.     Type and Frequency of Lightning

11-35.   Reporting Squalls

SECTION 5.   OBSERVING AND REPORTING PROCEDURES FOR
                         OBSCURATIONS

11-36.   General

11-37.   Observing Obscurations

11-38.   Reporting Obscurations

11-39.   Special Procedures for Volcanic Ash

11-40.   Operationally Significant Remarks for Obscurations