BY ORDER OF THE SECRETARY AIR FORCE …

1 BY ORDER OF THE SECRETARY OF THE AIR FORCE AIR FORCE manual 15-111 27 FEBRUARY 2013 Incorporating Through Change 2, 21 JANUARY 2016 Weather SURFACE WEATHER OBSERVATIONS COMPLIANCE WITH THIS PUBLICATION IS MANDATORY ACCESSIBILITY: This publication is available for downloading from the e-publishing website at RELEASABILITY: There are no releasability restrictions on this publication OPR: HQ USAF/A3O-WP Supersedes: AFMAN 15-111, 10 March 2009 Certified by: HQ USAF/A3O-W (Dr. Fred P. Lewis) Pages: 117 This manual implements Air FORCE Policy Directive (AFPD) 15-1, Atmospheric and Space Environmental Support.

2 It also implements Federal Meteorological Handbook No. 1 (FCM-H1) and the World Meteorological Organization (WMO) manual on Codes, Volume , Part A (WMO 306, Vol , Part A) aerodrome routine meteorological reports (FM-15 METAR) and aerodrome special meteorological reports (FM-16 SPECI) codes. It prescribes basic observing fundamentals and terms and establishes aviation code forms for recording and disseminating weather observations. It applies to all Active and Reserve Component organizations conducting weather operations, including government-contracted weather operations if stated in the Statement of Work or Performance Work Statement.

3 This Air FORCE (AF) manual (AFMAN) may be supplemented at any level, but all supplements must be routed to AF/A3O-WP, 1490 Air FORCE Pentagon, Washington, DC 20330-1490 for coordination prior to certification and approval. Refer recommended changes and questions about this publication to AF/A3O-WP using the AF 847, Recommendation for Change of Publication; route AF 847s from the field through Major Command (MAJCOM) publications/forms managers. Ensure that all records created as a result of processes prescribed in this publication are maintained in accordance with AFMAN 33-363, Management of Records, and disposed of in accordance with the Air FORCE Records Disposition Schedule (RDS) located in the Air FORCE Records Information Management System (AFRIMS).

4 The use of the name or mark of any specific manufacturer, commercial product, commodity or service in this publication does not imply endorsement by the Air FORCE . 2 AFMAN15-111 27 FEBRUARY 2013 SUMMARY OF CHANGES This interim change clarifies policy for augmenting automated meteorological observing systems (AMOS) during controlled airfield hours (paragraphs , , , , , , , , , , , , and ; Tables , , , and ), clarifies backup equipment and manual procedures (paragraphs , , , , , , , , and ) clarifies the definition of Local Standard Time (paragraph ), streamlines the barometer comparison/calibration procedures (paragraph and all sub-paragraphs), updates waiver authorities and reflects changes in responsibilities due to organizational changes (Chapter 1, paragraphs , , , , , , , , , , , , and ).

5 Chapter 1 INTRODUCTION 8 General.. 8 DELETED.. 8 Applicability of Procedures.. 8 Chapter 2 GENERAL OBSERVING INFORMATION 9 General.. 9 Automated Meteorological Observing Systems (AMOS).. 9 Fixed Meteorological Equipment.. 9 Certification Requirements.. 10 Station Information File.. 10 Accuracy of Time.. 10 Aviation Weather Code Forms.. 11 Observed Elements.. 12 Installation Observation Requirements.. 13 Unofficial Weather Reports.. 13 Points of Observation.. 13 Rounding of Figures and Values.

6 14 Alternate Operating Location (AOL).. 15 Weather Watch.. 15 Cooperative Weather Watch.. 16 Control Tower Observations and Weather Observing Location Actions.. 17 Observing Aids for Visibility.. 17 Figure Example Visibility Checkpoint Photograph .. 18 Aircraft Mishap.. 18 AFMAN15-111 27 FEBRUARY 2013 3 Supplementary Data for an Inactive or Parallel Runway.. 18 Instrument Procedures.. 19 Chapter 3 AUGMENTATION 20 Purpose.. 20 Augmentation.. 20 Supplementing AMOSs.. 21 Table Summary of Mandatory Supplementary Weather Conditions.

7 21 Back-up of an AMOS.. 22 Back-up Equipment.. 23 Maintenance Procedures.. 24 Chapter 4 OBSERVATION FORM ENTRIES 25 Introduction.. 25 ADS Procedures.. 25 Non-ADS Procedures.. 25 Figure Example AF 3803 Synoptic and Summary of the Day Entries .. 27 Corrections.. 30 Transfer and Disposition of Observation Records.. 32 Chapter 5 WIND 33 Introduction.. 33 Definitions.. 33 Wind Algorithms for AMOSs.. 33 Determining Standards.. 33 Table Summary of Wind Observing Standards.. 34 manual Observing Methods.

8 34 Table Beaufort Scale of Winds .. 35 Table Conversion of Miles Per Hour to Knots .. 36 Table Conversion of Knots to Miles Per Hour .. 36 Chapter 6 VISIBILITY 37 Introduction.. 37 Definitions.. 37 Visibility Algorithms for AMOS.. 37 Determining Standards.. 37 4 AFMAN15-111 27 FEBRUARY 2013 Table Reportable Visibility Values .. 39 manual Observing Methods.. 39 Table Example for Determining Prevailing Visibility .. 40 Chapter 7 RUNWAY VISUAL RANGE 41 Introduction.. 41 Definitions.

9 41 RVR Algorithms for AMOS.. 41 Determining Standards.. 41 Table RVR Reportable Values .. 42 manual Observing Methods.. 42 Chapter 8 PRESENT WEATHER 43 Introduction.. 43 Definitions.. 43 Present Weather Alogorithms for AMOS.. 46 Qualifiers.. 46 Table Automated Present Weather Reporting .. 47 Determining Standards.. 47 Table Intensity of Snow or Drizzle Based on Visibility .. 48 manual Observing Methods.. 48 Table Estimating Intensity of Ice Pellets .. 48 Table Intensity of Rain or Ice Pellets Based on Rate-of-Fall.

10 48 Other Significant Weather Phenomena Reported.. 49 Chapter 9 SKY CONDITION 50 Introduction.. 50 Definitions.. 50 Sky Condition Algorithms for AMOS.. 52 Determining Standards.. 52 Table Reportable Values for Sky Cover Amount .. 52 Table Criteria for Variable Ceiling .. 53 DELETED.. 53 manual Observing Methods and Procedures.. 53 Table Sky Cover Evaluation .. 54 AFMAN15-111 27 FEBRUARY 2013 5 Figure Illustration of Packing Effect .. 55 Table Examples of Sky Condition Summation .. 55 Table Convective Cloud Height Estimates.