National Weather Service
The Federal Meteorological Handbook (FMH) Number 1 titled, Surface Weather Observations and Reports , dated December 1995 is the definitive United States standard for the Aviation Routine Weather Report/Aviation Selected Special Weather Report (METAR/SPECI) code formats. It was compiled under the auspices of the Office of the Federal Coordinator for Meteorological Services and Supporting Research and embodies the work of meteorological code experts from the United States Departments of Commerce, Transportation, Defense, and Energy. The FMH-1 incorporates all of the United States' exceptions to the international METAR/SPECI format standard that is prescribed in the World Meteorological Organization's Publication No. 306 on Meteorological Codes.
Please note that the FMH-1 on this information page should not be considered the official signed copy, it is merely provided for your information. For information about how to order an officially signed copy, which also entitles you to a subscription of all future changes for a 5-year period, click here .