Federal Meteorological Handbook No. 1

FOREWORD

The fifth edition of Federal Meteorological Handbook No. 1(FMH-1), "Surface Weather Observations and Reports" embodies the United States conversion to the World Meteorological Organization's (WMO) Aviation Routine Weather Report/Aviation Selected Special Weather (METAR/SPECI, see Note 1) code formats. The U.S. implementation of METAR, as the national reporting code for surface weather observations, is a major step toward fulfilling a WMO and International Civil Aviation Organization (ICAO) goal of a common, world-wide aviation weather observation code form.

Because of the extended use (over 40 years) of the Surface Aviation Observations (SAO) code in this country and North America, the implementation of METAR/SPECI will necessitate a review of all associated meteorological operations within the public and private sectors. Consequently, the conversion to METAR/SPECI should not be viewed simply as a code replacement but rather a major change to our way of conducting business. METAR/SPECI will require a "paradigm shift" and will call for changes in both operational and organizational policies, procedures and practices.

In addition to converting coding and decoding software, the implementation of METAR/SPECI requires a modification to national observing and reporting practices. Some of these modifications have been incorporated into this edition. Over the next two years, as we gain additional experience with METAR/SPECI, it may become necessary to further modify the observing and reporting standards prescribed in this Handbook.

Consistent with the fourth edition, this edition: (1) acknowledges the use of automated surface weather observing systems; (2) integrates conventional and automatically observed data by adopting new standards for automated and manual observations; and (3) allows Federal agencies to prepare and issue agency-specific procedures and instructions for observing, reporting, and coding surface aviation weather observations. FMH-1 contains only Federal standards and does not contain agency-specific procedures and practices.

The Departments of Commerce, Defense, and Transportation will issue complementary METAR observing handbooks for their respective agencies. These handbooks will comply with the standards adopted in FMH-1 but may vary with respect to the manner in which these standards are met.



			Julian M. Wright, Jr.
			Federal Coordinator for Meteorological
			 Services and Supporting Research


Note 1: FM 15-X Ext. METAR and FM 16-X Ext. SPECI