National Weather Service United States Department of Commerce

Slow Moving Cold Front Moves into the Central U.S.

A slow moving cold front continues to move eastward across the U.S. this weekend. Behind the cold front is unseasonably cold weather and high elevation snows; ahead of the front, temperatures are more typical of mid-summer. The front separating these extremes will help focus heavy rain, with the potential for flash flooding extending from eastern New Mexico and western Texas to the Upper Midwest. Read More >


Heading Tables

WMO Tables from Manual 386

and National Tables

The tables that define the designators within the World Meteorological Organization Abbreviated Heading for bulletin identification to exchange data and products on the Global Telecommunication System are provided here for convenient access. The WMO published tables are contained in their Manual 386 PART II, attachment II-5. The tables provided here include all known current designator definitions including any changes up through CBS XII Session ( Geneva 2000 ) for implementation by November 2001. There are a few places in these tables where U.S. National Practices definitions are included, and/or are pending changes submitted through the Technical Study Groups in the next session of CBS.

Some WMO publications are available from the WMO in Geneva, Switzerland. The WMO Manual on Codes (Manual 306) can be found on their server. The tables from WMO Manual 386 are reproduced here to help in both encoding and decoding the communication headers used extensively throughout the meteorological community. The identifing header has a standard structure as shown here.

WMO Abbreviated Heading Reference Model
T1T2 A1A2ii   CCCC

The tables provided here can be used to both construct communication headings and for interpretation of the heading to determine the basic WMO code form and content of the bulletin.

The first (initial) Table A in this group also defines the maximum bulletin size for exchange on the GTS. Bulletins larger than this size must be segmented into parts to insure successful relay through telecommunication switching centers. This initial table defines the T1 "Data Type" and is a matrix table. From this table is access to all of the other defining tables through the designator parts within the heading structure model shown above.