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FCM-H1-2019, Federal Meteorological Handbook No. 1

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FCM-H1-2019, Federal Meteorological Handbook No. 1 U.S. DEPARTMENT OF COMMERCE/ National Oceanic and Atmospheric Administration OFFICE OF THE FEDERAL COORDINATOR FOR METEOROLOGICAL SERVICES AND SUPPORTING RESEARCH FEDERAL METEOROLOGICAL HANDBOOK No. 1 Surface Weather Observations and Reports FCM-H1-2019 Washington, D.C. July, 2019 CHANGE AND REVIEW LOG Use this page to record changes, notices and reviews. Change Number Page Numbers Date Posted Initials 1 2 3 4 5 6 7 8 9 10 Changes are indicated by a vertical line in the margin next to the change. Review Date Comments Initials THE OFFICE OF THE FEDERAL COORDINATOR FOR METEOROLOGICAL SERVICES AND SUPPORTING RESEARCH 1325 EAST-WEST HIGHWAY, SUITE 7130 SILVER SPRING, MARYLAND 20910 301-628-0112 [email protected] FEDERAL METEOROLOGICAL HANDBOOK NUMBER 1 SURFACE WEATHER OBSERVATIONS AND REPORTS FCM-H1-2019 Washington, D.C. July 24, 2019 iv Summary of Changes This change to FMH-1, published July 24, 2019, replaces the November 30, 2017 version and accomplishes the following general objectives: • Update new speci category with the following specific changes: Chapter 2: section 2.5.2 Aviation Selected Special Weather Report (SPECI), a. Criteria for SPECI, 6. PRECIPITATION with the following: o d). snow begins, ends, or changes intensity. v Table of Contents Contents CHANGE AND REVIEW LOG ........................................................................................ 1 Summary of Changes ................................................................................................... v Table of Contents ......................................................................................................... vi List of Tables ................................................................................................................ ix CHAPTER 1: INTRODUCTION ...................................................................................... 1 1.1 Purpose ................................................................................................................. 1 1.2 Applicability of Standards ...................................................................................... 1 1.3 Relation to Other Handbooks and Manuals ........................................................... 1 1.4 Format of This Handbook ...................................................................................... 1 1.5 Changes to The Handbook .................................................................................... 2 1.6 Agency Procedures and Procedural Changes ....................................................... 2 1.7 Reference Library .................................................................................................. 3 1.8 Unforeseen Requirements ..................................................................................... 3 1.9 Other Questions and Suggestions Regarding FMH-1............................................ 3 CHAPTER 2: SURFACE WEATHER OBSERVATION PROGRAM ............................... 1 2.1 General .................................................................................................................. 1 2.2 Scope .................................................................................................................... 1 2.3 Surface Weather Observation Program ................................................................. 1 2.4 Aviation Weather Observing Locations .................................................................. 1 2.5 Types of Reports ................................................................................................... 2 2.6 Observing Standards Applicable to All Stations ..................................................... 3 2.7 Recency of Observed Elements ............................................................................ 5 2.8 Dissemination ........................................................................................................ 5 2.9 Report Filing Time ................................................................................................. 6 2.10 Delayed Reports .................................................................................................. 6 CHAPTER 3: CERTIFICATION AND QUALITY CONTROL .......................................... 1 3.1 General .................................................................................................................. 1 3.2 Scope .................................................................................................................... 1 3.3 Certification Requirements .................................................................................... 1 3.4 Quality Control ....................................................................................................... 1 3.5 Quality Control Performed at Central Locations .................................................... 3 3.6 Customer Feedback .............................................................................................. 3 CHAPTER 4: OBSERVATIONAL RECORDS ................................................................ 1 4.1 General .................................................................................................................. 1 4.2 Scope .................................................................................................................... 1 4.3 Types of Records .................................................................................................. 1 CHAPTER 5: WIND ........................................................................................................ 1 5.1 General .................................................................................................................. 1 5.2 Scope .................................................................................................................... 1 vi 5.3 Wind Parameters ................................................................................................... 1 5.4 Wind Observing Standards .................................................................................... 1 5.5 Wind Reporting Standards ..................................................................................... 2 5.6 Summary of Wind Observing and Reporting Standards ..................................... 3 CHAPTER 6: VISIBILITY ................................................................................................ 1 6.1 General .................................................................................................................. 1 6.2 Scope .................................................................................................................... 1 6.3 Visibility Parameters .............................................................................................. 1 6.4 Visibility Observing Standards. .............................................................................. 1 6.5 Visibility Reporting Standards ................................................................................ 2 6.6 Summary of Visibility Observing and Reporting Standards ................................... 4 CHAPTER 7: RUNWAY VISUAL RANGE ...................................................................... 1 7.1 General .................................................................................................................. 1 7.2 Scope .................................................................................................................... 1 7.3 Runway Visual Range (RVR) Parameter ............................................................... 1 7.4 Runway Visual Range Observing Standards ......................................................... 1 7.5 Runway Visual Range Reporting Standards .......................................................... 1 7.6 Summary of Runway Visual Range Observing and Reporting Standards ............. 2 CHAPTER 8: PRESENT WEATHER .............................................................................. 1 8.1 General .................................................................................................................. 1 8.2 Scope .................................................................................................................... 1 8.3 Present Weather Parameters ................................................................................ 1 8.4 Present Weather Observing Standards ................................................................. 3 8.5 Present Weather Reporting Standards .................................................................. 4 8.6 Summary of Weather ............................................................................................. 8 CHAPTER 9: SKY CONDITION ..................................................................................... 1 9.1 General .................................................................................................................. 1 9.2 Scope .................................................................................................................... 1 9.3 Sky Condition Parameters ..................................................................................... 1 9.4 Sky Condition Standards ....................................................................................... 1 9.5 Sky Cover Reporting Standards ............................................................................ 3 9.6 Summary of Sky Condition Observing and Reporting Standards .......................... 5 CHAPTER 10: TEMPERATURE AND DEW POINT......................................................
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