Federal Coordinator

for

Meteorological Services and Supporting Research

Suite 1500, 8455 Colesville Road

Silver Spring, Maryland 20910

REPORT ON THE IMPLEMENTATION OF THE 

INTERDEPARTMENTAL METEOROLOGICAL DATA EXCHANGE

 SYSTEM (IMDES)

FCM-R12-1998

Washington, D.C.

August 1998
ii
iii

FOREWORD

The OFCM publication, Standard Telecommunication Procedures for Weather Data

Exchange (FCM-S3-1991), defines the methodology for linking the meteorological,

oceanographic and satellite Operational Processing Centers using standard telecommunication

procedures. The resulting system is called the Interdepartmental Meteorological Data

Exchange System (IMDES).

This document is the fourth report on Department of Commerce, Department of

Defense, and Department of Transportation implemention and operation IMDES. It is

intended as a coordinating mechanism to facilitate cooperation and enhance operation of the

system. It is a working document which will be revised periodically to reflect changes in

architecture or changes in modes of operation.

The report was prepared by the Working Group for Communications Interfaces and

Data Exchange (WG/CIDE), under the auspices of the Committee for Weather Information

Systems (CWIS).

Samuel P. Williamson

Federal Coordinator for

 Meteorological Services

 and Supporting Research
iv
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EXECUTIVE SUMMARY

This document is the fourth in a series of reports on the design, implementation and

operation of the Interdepartmental Meteorological Data Exchange System (IMDES). The

participants in the system, the National Weather Service and NESDIS/Department of

Commerce, the U.S. Navy and the U.S. Air Force/Department of Defense, and the Federal

Aviation Administration/Department of Transportation, are acting under the auspices of the

Office of the Federal Coordinator for Meteorological Services and Supporting Research

(OFCM).

This report describes the capabilities of the IMDES nodes, the communications

architecture, and the communications protocols used between the node systems. Also described

are the requirements for data exchange for each of the agencies in normal and backup

operations.

The IMDES was conceived as a formal structure for the routine exchange of

meteorological data and for mutual assistance when one of the participants required backup in

the event of operational difficulties. The IMDES has expanded in concept to include exchange

of large volumes of satellite data previously exchanged through the interdepartmental Shared

Processing Program (SPP).

The communications architecture for the IMDES consists of a combination of dedicated

circuits and networks connecting supported agencies to the major nodes. The nodes are

connected by a high-speed commercial Asynchronous Transfer Mode (ATM) service. The

ATM service was initially installed by the Department of Defense (DoD) as a part of the NavyAir Force Communications Initiative, under the direction of the Air Force Director of Weather

and the Oceanographer of the Navy. This document describes the IMDES operation and

agency plans for system upgrades over the next two years. 
vi
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TABLE OF CONTENTS

FOREWORD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii

EXECUTIVE SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v

TABLE OF CONTENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii

CHAPTER 1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

CHAPTER 2 IMDES OBJECTIVES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

CHAPTER 3 DESCRIPTION OF IMDES

3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

3.2 IMDES Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

3.2.1 Fleet Numerical Meteorology and Oceanography Center . . . . . . . . . . . . 3-1

3.2.2 Air Force Weather Agency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

3.2.3 National Weather Service Systems Operations Center . . . . . . . . . . . . . . 3-3

3.2.4 Naval Oceanographic Office . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

3.2.5 Automated Digital Weather Switch . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

3.2.6 National Centers for Environmental Prediction . . . . . . . . . . . . . . . . . 3-3

3.2.7 National Environmental Satellite, Data, and Information Service . . . . . . . 3-3

3.2.8 Federal Aviation Administration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4

3.2.9 National Ice Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4

CHAPTER 4 IMDES SYSTEM ARCHITECTURE . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

CHAPTER 5 IMDES DATA REQUIREMENTS FOR EXCHANGE AND BACKUP . . . 5-1

CHAPTER 6 IMPLEMENTATION PLANS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1

GLOSSARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . G-1
1-1

CHAPTER 1

INTRODUCTION

1.1 Purpose. 

The report documents the design and implementation of the IMDES. This report also

documents requirements for the IMDES and describes or references other Federal plans or

documents from which requirements are derived. 

1.2 Document Description. 

Chapter 2 describes the structure of the IMDES. Chapter 3 presents the overall IMDES

objective and each agency’s specific objectives. Chapter 4 discusses the capabilities of the

IMDES nodes and describes the data format that will be used by each agency. Chapter 5

discusses the individual agency data requirements for exchange and backup. Chapter 6 presents

the agency plans for the implementation of future IMDES functions at their nodes.

1.3 Other Federal Plans and Documents.

a. The Storage of Weather Product Information and the Exchange of Weather

Product Messages in Gridded Binary Form (WMO Code FM 92-VII Ext),

Edition (1), 1992, World Meteorological Organization: Geneva Switzerland.

b. Binary Universal Form for Data Representation (WMO Code FM 94 BUFR),

1988, World Meteorological Organization: Geneva, Switzerland.

c. ATM Forum working groups for the User-to-Network Interface (UNI), 

Network-to-Node interface (NNI) and Data Exchange Interface (DXI), ITU-T

Recommendation 1.36.1

d. Federal Plan for Cooperative Support and Backup Among Operational

Processing Centers, FCM-P14-1996, U.S. Department of Commerce, National

Oceanic and Atmospheric Administration, Federal Coordinator for

Meteorological Services and Supporting Research: Washington, D.C.

e. Standard Formats for Weather Data Exchange Among Automated Weather

Information Systems. FCM-S2-1994, U.S. Department of Commerce, National

Oceanic and Atmospheric Administration, Federal Coordinator for

Meteorological Services and Supporting Research: Washington, D.C.

f. Standard Telecommunication Procedures for Weather Data Exchange. 

FCM-S3-1991, U.S. Department of Commerce, National Oceanic and

Atmospheric Administration, Federal Coordinator for Meteorological Services

and Supporting Research: Washington, D.C.
1-2

g. Applicable Documents and Standards:

 

MIL-STD-1777 Internet Protocol

MIL-STD-1778 Transmission Control Protocol

MIL-STD-1780 File Transfer Protocol

ITU-T Recommendation V.35 Communications Interface

ITU-T Recommendation I.22 Frame Relay

IEEE 802.3 Ethernet

IEEE 802.6 FDDI

EIA-449 Communications Interface
2-1

CHAPTER 2

 IMDES OBJECTIVES

2.1 General Objectives.

a. To provide the means through which the major processing centers of the U.S.

Government will exchange meteorological data for use in daily operations and for

backup. 

b. To implement the specific requirements defined in the Federal Plan for Cooperative

Support and Backup Among Operational Processing Centers, FCM-P14-1996. 

2.2 Operational Objectives. 

a. To provide the communications architecture, front-end processing capability, and

procedures to allow the major processing centers to exchange meteorological,

oceanographic, and satellite data.

b. To define the data volume, delivery requirements, and data formats used among

major processing centers.

2.3 Backup Objectives.

a. To provide the communications architecture, front-end processing capability,

procedures, and data storage to all major processing centers to backup each other. 

b. To define data volume, delivery requirement, data formats, and storage

requirements for one major processing center to backup another.

c. To implement specific backup requirements as defined in FCM-P14-1996. 
3-1

CHAPTER 3

DESCRIPTION OF IMDES

3.1 Introduction.

This chapter describes the structure of the IMDES and presents a brief discussion of the

structure of each of the agencies’ front-end processing systems that function as IMDES nodes.

3.2 IMDES Structure.

Figure 1 depicts the four primary IMDES nodes and the five secondary nodes. An IMDES

primary node is an agency which has, as a part of its mission, the requirement to provide

substantial amounts of unique environmental data to other agencies of the U.S. government.

Primary nodes are usually interconnected with a high-speed (56 kbps or higher)

communications network. An IMDES secondary node is an agency which, to a more limited

degree, provides unique environmental data to other U.S. Government agencies. Secondary

nodes do not have the data volume requirements to justify connecting to a high-speed

communications network.

3.2.1 Fleet Numerical Meteorology and Oceanography Center (FNMOC).

FNMOC is located in Monterey, California, and is a third echelon command reporting to the

Commander, Naval Meteorology and Oceanography Command (COMNAVMETOCCOM). 

The FNMOC mission is to provide responsive quality meteorological and oceanographic

(METOC) automated numerical guidance and information to Navy and other Department of

Defense activities worldwide to increase safety of forces and to optimize the use of platforms,

weapons, sensors and facilities. FNMOC provides real-time global METOC analyses,

forecasts, and data for use in support of all elements of fleet sensors and weapons systems. 

FNMOC is the Numerical Weather Prediction (NWP) processing center for the DoD. FNMOC

is connected to the other major environmental processing centers and is a primary IMDES

node.

3.2.2 Air Force Weather Agency (AFWA).

AFWA is located in Omaha, Nebraska. The AFWA mission is to build the world’s most

comprehensive weather database and apply the information in real time to satisfy the

operational requirements of the National Command Authorities, Department of Defense,

combat forces of the U.S. Air Force and Army, and the multimillion-dollar, weather-sensitive

Air Force Precedence 1-1 programs controlled by the Secretary of the Air Force. AFWA is the

Satellite Processing Center for the DoD. AFWA is connected to the other major environmental

processing centers and is a primary IMDES node.
3-2

Figure 1 IMDES Structure
3-3

3.2.3 National Weather Service Systems Operations Center (SOC).

The SOC is located in the NOAA complex in Silver Spring, MD and is the hub for NOAA

communications. The National Weather Service Telecommunication Gateway (NWSTG), a

facility operated by the SOC, is the interface to the World Meteorological Organization

(WMO) Global Telecommunication System (GTS) for the U.S. Government. The NWSTG

receives atmospheric and oceanographic observations, forecasts, and other data from WMO

member nations. These data are stored by the NWSTG and forwarded to other departments of

the government. FNMOC and AFWA receive data from the NWSTG. The IMDES includes

the NOAA metropolitan network at the SOC which connects other NOAA agencies in the

Washington, D.C. The SOC is a primary IMDES node.

3.2.4 Naval Oceanographic Office (NAVOCEANO).

NAVOCEANO is located at Stennis Space Center, MS and is the Navy’s center of expertise in

global and littoral oceanographic data collection and oceanographic products. These data

include sea surface temperature, bathymetry, ocean currents, water clarity, sea floor bottom

sediment, hydrography, coean modeling and prediction. NAVOCEANO is also the primary

government center responsible for surveying ocean topology. NAVOCEANO provides all of

the oceanographic data to operational DoD units. NAVOCEANO is a primary IMDES node.

3.2.5 Automated Digital Weather Switch (ADWS).

The ADWS is located at Tinker AFB, OK and is the central database for observational data

and text messages for DoD. ADWS Tinker, along with ADWS Croughton, UK and ADWS

Hickam AFB, HI, provide observational data and meteorological products obtained from the

SOC to all DoD weather processing centers, bases, deployed units, and ships at sea. ADWS

Tinker is a secondary IMDES node.

3.2.6 National Centers for Environmental Prediction (NCEP).

The NCEP, located in Suitland, Maryland, is the major weather processing center for NOAA. 

NCEP runs atmospheric prediction models which provide data for the NWS offices throughout

the U.S., for the Federal Aviation Administration, and other domestic and international

agencies. NCEP is the backup processing center for FNMOC. NCEP is connected to the

other major environmental processing centers through the SOC. NCEP is a secondary IMDES

node.

3.2.7 National Environmental Satellite, Data, and Information Service (NESDIS).

The NESDIS is located in Suitland, Maryland, and is the organization responsible for

processing meteorological satellite (METSAT) data for NOAA. METSAT data collected by

NESDIS is relayed in real-time and near real-time to other U.S. government agencies. NESDIS

supplies satellite data that was previously exchanged through the Shared Processing Program to

other IMDES nodes. NESDIS is a secondary IMDES node.
3-4

3.2.8 Federal Aviation Administration (FAA).

The FAA Weather Message Switching Center Replacement (WMSCR) is a dual hub facility

located in Atlanta, Georgia, and Salt Lake City, Utah, and provides weather messages to FAA

facilities throughout the U.S. The WMSCR is connected to the SOC through the dedicated

FAA NADIN Packet Switched Network (PSN). WMSCR is a secondary IMDES node.

3.2.9 National Ice Center (NIC).

The National Ice Center is located in Suitland, Maryland. NIC is a secondary IMDES node. 
4-1

CHAPTER 4

IMDES SYSTEM ARCHITECTURE

4.1 Introduction.

This chapter describes the capabilities of each IMDES node, the communications architecture,

communications front-end computer systems, and communications protocols used between each

node.

4.2 General Overview.

The IMDES is comprised of communications front-end processing computers, data servers, 

high-speed communications networks and dedicated communications circuits. These

components work together to provide an automated data ingest and distribution capability for

all agencies concerned. The IMDES architecture components also serve other functions within

each agency. 

4.3 IMDES Characteristics. 

Standards have been established for communications between nodes. These standards include

communications protocols, data formats, data storage and retrieval procedures, and data

delivery/availability requirements. Each IMDES agency has established a Memorandum of

Agreement (MOA) and, if desired, an Interface Specification (IFS), which describes each

agency’s obligation with regard to IMDES. Within these MOA and IFS certain factors remain

constant. These include communications protocol and data format.

4.3.1 Communications Protocol. 

All IMDES primary nodes will communicate using Transmission Control Protocol/Internet

Protocol (TCP/IP), along with File Transfer Protocol (FTP), Hypertext Transfer Protocol

(HTTP), ATM User Node Interface (UNI) or Network Node Interface (NNI) specifications,

and other protocols as required to perform data exchange. Agencies may agree to push or to

pull data as best suits an agency’s operations. Agencies negotiate file transfer procedures

including logins, directory, data retention, etc. Agencies mutually define data delivery and

availability requirements, and system recovery procedures. Secondary nodes may use ITU-T

Rec. X.25 access protocol for connectivity to IMDES through the primary node. 

4.3.2 Data Format. 

All IMDES primary nodes exchange data in Gridded Binary (GRIB) Format, Binary Universal

Format (BUFR), and other WMO code formats. Specific data formats are mutually arranged

by the sending and receiving agencies.
4-2

4.4 IMDES Network and Circuits. 

IMDES nodes are connected by high-speed communications networks, dedicated circuits, and

government networks.

4.4.1 High-Speed Communications Networks.

High-speed networks used by IMDES include the High-Speed Asynchronous Transfer Mode

(ATM) Weather Communication Network (HAWCNet), implemented by DoD. The

HAWCNet connects FNMOC in Monterey, CA, AFWA in Offutt AFB, NE, the SOC in Silver

Spring, MD, and NAVO in Stennis Space Center, MS. HAWCNet will be replaced with the

Defense Information Systems Network (DISN) ATM Service – Unclassified (DAS-U) during

Fiscal Year 1999. DoD will coordinate the transition of all agencies from HAWCNet to 

DAS-U. 

The Fiber Network Service (FNS) metropolitan area network connects the SOC in Silver

Spring, MD, to NESDIS, NCEP, and the NIC in Suitland, MD.

4.4.2 Dedicated circuits.

Dedicated circuits are used to connect ADWS Tinker to other IMDES nodes. Also, all IMDES

secondary nodes are connected to primary nodes through dedicated circuits.

4.4.3 Other Government Networks.

Some government departments run separate Internet compatible networks; e.g., DoD’s

Unclassified Internet Protocol Router Network (NIPRNET), National Science Foundation

Network (NSFNet), and the Defense Research and Engineering Network (DREN). Some state

sponsored networks connect universities and research institutions; e.g., the California Research

and Engineering Network (CALREN). The FAA operates NADIN PSN, an X.25 network to

connect their facilities and provide connections for other Government agencies. IMDES nodes

may be connected to one or more of the government sponsored networks.
5-1

CHAPTER 5

IMDES DATA REQUIREMENTS FOR EXCHANGE AND BACKUP

5.1 Introduction.

This chapter describes the requirements for data exchange for each of the agencies in normal

and backup operations. Agencies mutually define data exchange requirements for normal

operations in Table 1 and for backup situations in Table 2. The projected date in Tables 1 and

2 is 2003. 

5.2 Data Types.

The data types utilized by the agencies in IMDES include gridded data fields, other

alphanumeric text, and satellite images.

5.2.1 Gridded Data.

WMO GRIB is recognized by the U.S. Government as the official standard for gridded data

products, and as such, all gridded products and data exchanged among the major processing

centers of the U.S. Government will be in GRIB format. The resolution of grids, orientation

of grids, and other GRIB parameters will be consistent with agency data exchange agreements. 

All agencies will include the Grid Definition Section (GDS) on all gridded data and products.

5.2.2 Alphanumeric text.

Alphanumeric text includes both free text and coded messages in accordance with WMO and

OFCM manuals on codes.

5.2.3 Satellite data.

The Shared Processing Operations Working Group (SPOWG) coordinates the exchange of

satellite data between IMDES nodes. 

5.3. Primary Node Requirements.

Some primary nodes have unique data exchange requirements. Solutions to these unique

requirements are the responsibility of the agency or agencies involved.

5.3.1 NWS unique data exchange requirements. 

Alphanumeric data and text products which must ultimately transfer through the NWSTG must

not exceed 3,800 octets per file or message. Binary data (GRIB, BUFR, etc.) must not exceed

15,000 octets per file or message. Data which transfers to other NOAA agencies without

going through NWSTG are not restricted. All data/products destined for the Global

Telecommunications System (GTS) must transfer through NWSTG. 
5-2

5.3.2 AFWA unique data exchange requirements. 

AFWA will perform a gateway function to other Air Force customers. If required, the NOAA

and Navy products received over IMDES will be processed and reformatted into product

formats acceptable to the supported destination system. AFWA will exchange data in WMO

format, FCM-S2 format, and unique binary formats under bilateral agreement. The specific

types of information to be shared is identified in FCM-P14-1996.

5.3.3 ADWS Tinker unique data exchange requirements. 

The ADWS at Tinker AFB, OK, currently exchanges data with three other IMDES primary

nodes and the FAA’s WMSCR, a secondary IMDES Node. Data formats are currently

restricted to those specified in Air Force regulations. Software restrictions at the ADWS

inhibit the ability to reroute data from one IMDES center to another if the products are not in

the presently recognized formats or exceed the ADWS maximum product size. For the near

future, ADWS Tinker will continue to exchange data through the existing FCM-S3 X.25

interface. ADWS Tinker is in the process of upgrading to an IMDES compliant (DISN

compliant) network capability.

5.3.4 FNMOC unique data requirements. 

FNMOC will accept and generate data in WMO formats and other formats as needed to meet

mission requirements. FNMOC will exchange data with IMDES agencies in WMO formats;

primarily GRIB for gridded fields and BUFR or ASCII text for alphanumeric text data. 

Satellite data will be exchanged in the formats as defined by the SPOWG.

5.3.5 NAVOCEANO unique data requirements. 

NAVOCEANO will accept and generate data in WMO formats and other formats as needed to

meet mission requirements. NAVO will exchange data with IMDES agencies in WMO

formats; primarily GRIB for gridded fields and BUFR or ASCII text for alphanumeric text

data. Satellite data will be exchanged in the formats as defined by the SPOWG.

5.3.6 FAA unique data requirements. 

The current data requirements are for the exchange of alphanumeric data in WMO format

between NWSTG and WMSCR and between ADWS and WMSCR. In the future, the WMSCR

will exchange alphanumeric data, as well as vector graphic and gridded binary product data

with the NWSTG. The WMSCR will adhere to WMO and FCM-S2 formats. The

file/message sizes will range up to 1,000 octets per file or message. During back-up

operations, the IMDES Nodes supporting FAA will provide backup support as identified in

FCM-P14-1996.
5-3

DoD/FNMOC

Data Type Send Receive

Current Projected Current Projected

Fields 12 GB 2.4 TB 1.6 GB 160 GB

Sat 1 GB 200 GB 5 GB 1 TB

Other(1) 3 GB 600 GB 1.4 GB 140 GB

DoD/NAVOCEANO

Send Receive

Current Projected Current Projected

Fields 300 MB 1.2 GB 100 MB 100 MB

Sat 100 MB 100 MB 1 GB 2 GB

Other 100 MB 100 MB 100 MB 100 MB

DoD/AFWA

Send Receive

Current Projected Current Projected

Fields 156 MB 300 MB 3 GB 6 GB

Sat 10 GB 20 GB 37 MB 50 MB

Other 0 5 GB 2.3 GB 4 GB

DoC/NWS

Send Receive

Current Projected Current Projected

Fields 1.9 GB 225 GB 885 MB 104 GB

Sat N/A(2) N/A N/A N/A

Other 671 MB 6 GB 402 MB 3.5 GB

DoT/FAA

Send Receive

Current Projected Current Projected

Fields N/A N/A 2.9 MB(4) N/A

Sat N/A N/A 27.8 MB(5) 55.6 MB(5)

Other 11.7 MB(3) N/A 5.9 MB(3) N/A

DoD/ADWS

Send Receive

Current Projected Current Projected

Fields 500 MB 630 MB 80 MB 319 MB

Sat 0 0 0 0 

Other 0 0 0 0

Table 1. Routine Daily Data Types and Quantities
5-4

DoD/FNMOC

Data Type Send Receive

Current Projected Current Projected

Fields 12 GB 2.4 TB 1.6 GB 160 GB

Sat 1 GB 200 GB 5 GB 1 TB

Other(1) 3 GB 600 GB 1.4 GB 140 GB

DoD/NAVOCEANO

Send Receive

Current Projected Current Projected

Fields 300 MB 1.2 GB 100 MB 100 MB

Sat 100 MB 100 MB 1 GB 2 GB

Other 100 MB 100 MB 100 MB 100 MB

DoD/AFWA

Send Receive

Current Projected Current Projected

Fields 156 MB 300 MB 3 GB 6 GB

Sat 10 GB 20 GB 37 MB 50 MB

Other 0 5 GB 2.3 GB 4 GB

DoC/NWS

Send Receive

Current Projected Current Projected

Fields 1.9 GB 225 GB 885 MB 104 GB

Sat N/A(2) N/A N/A N/A

Other 671 MB 6 GB 402 MB 3.5 GB

DoT/FAA

Send Receive

Current Projected Current Projected

Fields N/A N/A 2.9 MB(4) N/A

Sat N/A N/A 27.8 MB(5) 55.6MB(5)

Other 11.7 MB(3) N/A 5.9 MB(3) N/A

DoD/ADWS

Send Receive

Current Projected Current Projected

Fields 500 MB 630MB 80MB 319 MB

Sat 0 0 0 0

Other 0 0 0 0

Table 2. Backup Daily Data Types and Quantities
5-5

Notes:

General: All the numbers in tables 1 & 2 are estimates based on center specific assumptions

and subjective evaluations. No attempt has been made to reconcile data quantities between

IMDES nodes. 

(1) Includes derived imagery products.

(2) N/A- Information was not available at time of publication.

(3) Source of data: “National Weather Service Telecommunication Gateway (NWSTG) to

Weather Message Switching Center Replacement (WMSCR)”, NAS-IR-90022507, Revision A,

March 8, 1991, Part 1, Appendices I & II.

(4) Source of data: “National Weather Service Telecommunications Gateway To Weather

Message Switching Center Replacement (WMSCR)”, NAS-IR-90022507, February 27, 1987,

Part 2, Appendix I.

(5) Source of data: “NAS Weather Data Communications Architecture Analysis Report”,

March 1996.
6-1

CHAPTER 6

IMPLEMENTATION PLANS

6.1 Introduction.

This chapter addresses implementation plans for data exchange between the various IMDES

nodes.

6.2 Implementation Plans for NWS.

The NWS/OSO in Silver Spring, MD serves as the hub for Washington, DC area NOAA

agencies and provides access to other IMDES nodes through the HAWCNet. NWS/OSO will

be an active participant in the migration of HAWCNet to the DAS-U. Additional

communications services may also be required as plans for mutual backup with FNMOC

materialize and are put into place.

6.3 Implementation Plans for AFWA.

AFWA is currently a primary IMDES node and will be an integral part of the transition of

HAWCNet to the DAS-U. AFWA, as the DoD center of expertise in satellite processing, will

continue to provide increased satellite data capability to the IMDES centers.

6.4 Implementation Plans for ADWS.

The ADWS will undergo major upgrades during the next 2 years. Among these changes will

include the capability to support modern communications protocols, making ADWS data

accessible to a larger number of agencies. ADWS will continue in its role as the primary

supplier of observational data for DoD. Additional communications capability may be added

to ADWS as a part of this upgrade. ADWS could become a primary IMDES node as a part of

the transition of HAWCNet to the DAS-U.

6.5 Implementation Plans for FNMOC.

FNMOC is currently a primary IMDES node and will be an integral part of the transition of

HAWCNet to the DAS-U. FNMOC, as the DoD center of expertise in numerical modeling

and weather prediction, will continue to provide meteorology and oceanography predictions to

all IMDES agencies, as well as other government agencies and allies.

6.6 Implementation Plan for NAVOCEANO.

NAVOCEANO is currently a primary IMDES node and will be an integral part of the

transition of HAWCNet to the DAS-U. NAVOCEANO, as the DoD center of expertise in

numerical oceanography and oceanographic prediction, will continue to provide oceanography

predictions to all IMDES agencies, as well as other government agencies and allies.
6-2

6.7 Implementation Plans for FAA.

FAA will continue in its role as a principal user of NWS and AFWA products and will remain

a secondary IMDES node.
G-1

GLOSSARY

AFDIGS Air Force Digital Graphics System

ADWS Automated Digital Weather Switch

AFGWC Air Force Global Weather Center

AFOS Automation of Field Operations and Services

AFWA Air Force Weather Agency

ATM Asynchronous Transfer Mode

CAWIS Committee for Automated Weather Information Systems

CFEP Communication Front End Processor

CNS Consolidated NOTAM Service

COMNAVMETOCCOM Commander, Naval Meteorology and Oceanography Command

DEF Data Exchange Format (FCM-S2)

DoC Department Of Commerce

DoD Department of Defense

DoT Department of Transportation

DPS Distributed Processing System

FAA Federal Aviation Administration

FAX Weather Facsimile

FCM-P14 Federal Plans for Mutual Support and Cooperative Backup

Among Operational Processing Centers

FCM-S2 Standard Formats for Weather Data Exchange Among Automated

Weather Information Systems

FCM-S3 Standard Telecommunication Procedures for Weather Data

Exchange Among Automated Weather Information Systems

FLENUMMETOCCEN Fleet Numerical Meteorology and Oceanography Center

FNMOC Fleet Numerical Meteorology and Oceanography Center

Green Book FCM-S3

GRIB Gridded Binary data format

HAWCNet High–speed ATM Weather Communication Network

IMDES Interdepartmental Meteorological Data Exchange System

ITUT-T International Telecommunication Union Telecommunication 

Standardization Sector

NADIN National Data Interchange Network

NAVOCEANO Naval Oceanographic Office

NWS National Weather Service

NWSTG National Weather Service Telecommunications Gateway

OFCM Office of the Federal Coordinator for Meteorological Services

and Supporting Research

OMB Office of Management and Budget

PSN Packet Switched Network

POPS Primary Oceanographic Prediction System

Red Book FCM-S2

SDHS Satellite Data Handling System

SPS Satellite Processing System
G-2

WG/CIDE Working Group for Communications Interfaces and Data

Exchange

WMO World Meteorological Organization

WMSCR Weather Message Switching Center Replacement