NOAA History Banner
gold bar divider
home - takes you to index page
about the site
noaa - takes you to the noaa home page
search this site
white divider

arrow Tools of the Trade
arrow Weather Prediction and Detection Technology

Stories and Tales of the Weather Service - Technology Tales

The National Weather Service Gateway


James L. R. Fenix

NOAA/National Weather Service
Silver Spring, Maryland


The National Weather Service (NWS) Gateway is today a major component of the NWS Telecommunication Gateway (NWSTG). The Gateway began as a manual data collection and distribution communications center in Washington, D.C., during the Second World War. In 1942 the Joint Meteorological Committee was established and a Central Analysis Center was created in support of the war effort. By 1944, the U.S. Weather Bureau, Washington, D.C., communications center used three teletypewriter machines to accomplish its mission.

By October 1947, the International Meteorological Organization was reformed, andpicture of letter of appreciation the World Meteorological Organization (WMO) was established in Geneva, Switzerland. This new organization established the Global Telecommunication System (GTS) within the World Weather Watch in 1951. Through international agreements for the exchange of meteorological data, communication circuits were established with the U.S. Weather Bureau from various international meteorological centers. The exchange became well established by the mid 1950's and the Washington center was starting to became one of the first GTS Regional Telecommunication Hubs (RTH) for the WMO World Weather Watch Program.

The U.S. Weather Bureau, now part of the Environmental Science Services Administration, established its communications center in the Suitland Federal Center in suburban Washington, D.C. In 1954 the Weather Bureau, Navy, Air Force, MIT, and U of Chicago formed a Joint Numerical Weather Prediction Forecast Unit at Suitland MD adjacent to this growing source of raw meteorological and hydrological data. Here the communications center was now operating nine Teletype Corporation teletypewriters including four Model 28 Automatic, Send/Receive (model 28ASR); four Model 28 Receive Only (model 28RO); and one Model 19 Automatic Send/Receive (model 19 ASR).

picture of man at teletypeAmong other circuits, these teletype machines were connected to a local administrative circuit, a circuit connecting local forecast offices, the Civil Aeronautics Administration (CAA), the predecessor organization to the Federal Aviation Administration (FAA), and a military weather circuit. The military was a provider of significant amounts of data collected through an extensive network of radio receiver sites to intercept foreign weather broadcasts. The CAA also provided data from foreign locations through the WMO's GTS. Included in these connections were radio links to some overseas locations such as Brazil. Most of these circuits operated, using punch paper tape, at a speed of 74 baud (100 words per minute), using WMO alphabet 2 (BAUDOT) code. The Washington center was now in the early stages of a major WMO RTH.


The Weather Bureau Washington communications switch by mid 1960 was connected to over 23 FAA Service O circuits, 6 Service C circuits, 60 Service A circuits, 4 RAWARC circuits, and several facsimile circuits.

The military line to the Air Force located at Tinker Air Force Base, Oklahoma, was an automated computer-to-computer directly connected circuit to the Gateway IBM 2908 controller operating through a RIXON modem at 3600 bits per second. This was the first high-speed communications circuit for the center in Suitland, Maryland.

The Weather Bureau Communications (WBC) Center, well established in Suitland, Maryland, by early 1965, was feeding the Joint Numerical Weather Prediction Center (JNWP) with the observational data needed to make surface and upper air analysis and forecast charts. The JNWP was jointly operated by the Weather Bureau Office and the U.S. Air Force Weather Service. The communications center began passing observational data to the JNWP by punching cards from paper tape and reading them into an IBM 1401 computer. The electrical delivery of data directly into a computer was developed in mid 1966. This capability started the true automation of the WBC center in Washington, D.C.

By early 1966, the center acquired two IBM 360 model 30 computers that were tiedwomen at teletype to the communications switching center teletype circuits with electrical interfaces provided with an IBM 2702 communications controller and a modified IBM 2908 communications controller for unique weather protocols. These communication controllers came with the delivery of the IBM 360 model 30's in 1966. The machines collected all of the observational data and placed the data on MEMOREX 2314 disk drives for computer ingest into the new Automated Data Processing software where data recognition and decoding was accomplished. The IBM 360 mainframe was running a new IBM communications software operating system called Communications Control and Applications Program (CCAP). This software was heavily modified for weather data processing. The software provided the data for the JNWP model software and was the central nucleus for true automated data switching between the many circuits connected to the communication controllers . The IBM 2702 replaced the manual tearing of paper tape and the FAA lines [Service A, C, and O] feed directly into them at 100 words per minute.

The first international high-speed circuit was implemented with Tokyo, Japan, in July 1969, using Fujitsu modems at 2400 bps with 75 baud back channels utilizing the WMO bisync protocol (alphabet 5). In January 1970, a 2400 bps link was installed with Europe connecting Washington with Offenbach, then Paris, and on to Bracknell. The Washington RTH was the only automated computer center as a component on the GTS at this time. The generated products from the JNWP included manually drawn weather charts that were transmitted on analog facsimile circuits using ALDEN Corporation flat-bed scanners.


Three IBM 360 model 40's were purchased in early 1970 to upgrade the capabilities of the message switching functions. They were soon integrated into the communications center and the CCAP software was enhanced to transmit and receive message traffic automatically on many additional lines to replace the manual switching methods using the teletypewriters paper tape for receipt and transmission. A new IBM 2703 communication controller was added to the IBM 360 for direct line attachment. These communication controllers supported interface speeds from 50 baud BAUDOT to 3600 bps ASCII. The IBM 360 computers were linked together using shared disk technology operating with the Memorex 2314 disk drives. One 360 model 40 was loaded with a new DOS operating system for the decoding and relay of the decoded data to the models. Additional links were installed using the new WMO bisynchronous communication protocols in ASCII character form, dropping the older BAUDOT 5-level tape code.

By 1974, new communication controllers were installed. They were Interdata 50 computers with interrupt cards and line driver software directly connected to the IBM 360 Model 40 computer mainframes. The NWS was now supporting a major computerized WMO Regional Telecommunications Hub (RTH) of the growing automated GTS. This new computer was operated by the Washington RTH and was the only one located in North America, making it a major hub of the GTS.


By late 1974, the Gateway had evolved to a completely automated switching center utilizing three IBM 360 model 40 computers for switching and decoding and an IBM 360 model 30 computer for facsimile processing and transmission. The model 30 was modified from its role of feeding the National Meteorological Center (NMC) computer model software to a support role in the automation of facsimile transmissions and the IBM 360 model 40's took on the task of communications with the NMC. These same model 40's supported the switching of the majority of the other circuits, which now numbered close to 90. The WMO international links had increased in number and lines operated to Brazil, Buenos Aires, Tokyo, Bracknell, and Toronto. Many of the circuits connected to the communications center were installed in support of aviation operations. With the support of the FAA, many lines had been installed to the Pacific, Central America, and the Caribbean Area as well as across the United States.

The national circuits included many FAA circuits including the Automatic Fixed Telecommunications Network supporting the International Civil Aviation Organization (ICAO). The military (Air force and Navy) circuits linked the NWS offices throughout the 48 states with data from military bases. The commercial air line community was supported directly from the IBM 360 Model 40 systems on dedicated circuits from the IBM 2908 at 1050 bps ASCII with tailored flight wind products, and the FAA users were provided GRID data and overseas aviation observations and forecasts for relay to many users at 2400 bps from their Weather Message Switching Center located in Kansas City, Missouri. The manual facsimile broadcasts were changed to automated transmissions in 1975 and DIFAX encoded methods were employed. This was accomplished with new Interdata 50 communication controllers which were programmed especially for analog transmission using NWS designed communication interface boards. This allowed the removal of the old ALDEN Corporation flat-bed scanners. The remaining hand-drawn charts were now done in the World Weather Building miles away from the communications center. They were transmitted to the facsimile system on dedicated lines from digitizers and curve plotters located next to the forecasters.

The National Oceanic and Atmospheric Administration (NOAA) administrative traffic function, which required manual reading of messages before switching to local circuits or to the AUTODIN communications system, was moved to the World Weather Building in 1974, and new lines connecting the automated message switch in Suitland with the NOAA message center were installed for exchange of needed meteorological traffic not received with proper message identification.


The 1976 time frame saw the development of the Weather Service's Automation of Field Operations and Services (AFOS) communications system. The NMC communications switching system began distributing large amounts of NMC products to the Weather Service field offices through the Gateway connection to a new Systems Monitoring and Control Center (SMCC). The use of the name Gateway for the communications switching system now began. This began the Gateway exchange of large volumes of centrally produced products for delivery to the Weather Service Forecast Offices across the United States. The major international centers were evolving which demanded larger volumes of data and products to be exchanged. This required increased circuit speeds and by 1980 many international circuits were operating at 4800 bps using the WMO ASCII (alphabet 5) format. The NMC was producing larger and larger global forecast fields from the models. The military exchange increased and circuit speeds increased to 4800 bps with dual links installed for backup with the Air Force's Automated Weather Network located in Carswell Air Force Base, Texas. Links to Toronto, Canada, and many federal agencies were now operating at speeds of 4800 bps.


The Gateway began a major upgrade plan in 1979 and a redesign of the Gateway was undertaken by NMC. By 1982, the Gateway was again upgraded and the IBM 360 model 30 and model 40's were replaced with IBM 4341 mainframes. The operating software installed on the new mainframes was the Virtual Machine (VM) operating system. This allowed the continuation of the CCAP switching function as it moved from the IBM 360 model 40 to the IBM 4341. The lines of communication had grown to 120 circuits and the interface to the new NMC model producer was changed to a disk sharing process for rapid exchange of data and products between the two computer centers. New Concurrent 3210 communication controllers were designed and programmed between 1979 and 1982 to replace the older IBM 2702 and 2703 controllers driving the older, low-speed circuits. The Gateway had replaced MEMOREX 2314 disk storage devices with IBM 3330 disks in 1982. The NMC aviation model was producing forecast fields in a new binary code form called GRIB by 1986. The WMO newly agreed upon X.25 communications protocol in 1983 was installed at the Gateway in 1985, after the purchase of the IBM 3705 and IBM 3725 communication controllers. These devices handled the WMO connections that operated as ASCII at 4800 bps, 9600 bps, and began to use the new X.25 protocol.

New circuits were installed between the Gateway and Tokyo RTH and between the Gateway and the Bracknell RTH using X.25 protocol in 1987. At this same time, a suite of new circuits were established. This was known as the Family of Services data distribution system and was established to provide the data available at the Gateway to the general user community. The older 1050 bps speed connections to dedicated air line users were dropped. The Numerical Products Service was established for the delivery of new binary GRIB coded aviation forecast gridded products to the general user community at 4800 bps using the X.25 protocol. The connection to the Navy Fleet Numerical Oceanographic Center was upgraded to X.25 protocol by 1988.


The Gateway was a part of a new NWS Headquarters reorganization and was moved on paper into the newly formed Office of Systems Operations in 1986. This moved the management of the Gateway from the NMC's Automation Division to the Systems Operations Center under the Office of Systems Operations. However, it was left operating at Suitland Federal Office Building Number 4 along with the AFOS Systems Monitoring and Coordination Center.

The Gateway was now a part of the NWSTG, a major provider of data and products for the NWS Forecast Offices, a major RTH center on the WMO GTS Main Trunk Network, a front-end data distribution center for the NMC, a major aviation meteorological data provider for the FAA, and the provider of the Family of Services data streams on 4 separate circuits. The NMC had a role as one of two World Area Forecast Centers (WAFC) for ICAO-generated products. An even larger set of forecast products was available, which caused an increase in data flow. The other WAFC for ICAO support was Bracknell, England. Thus, there was an increase in the data exchange between the two centers and this required the Gateway to increase the Bracknell GTS link line speed to 9600 bps by 1987 and later to 14.4 Kbps to meet the exchange requirements. The Gateway added new IBM 3375 disk drives for added capacity in 1987 and in 1988 for the AFOS binary graphics products and WAFC GRIB.

New digital graphics products for supporting a new NWS field upgrade to replace AFOS was started in 1987. The Gateway began the development of a new interface at 56 Kbps to meet the new Advanced Weather Interactive Processing System (AWIPS). The initial phase was a system called the Information Stream for AWIPS NOAAport (ISPAN) that required multiple virtual circuits for ASCII, BUFR, GRIB, and Red-Book digital Graphics coded products for transmission to a major NWS modernization development in Norman, Oklahoma, and Denver, Colorado. There, new field automated work station sites were being established and required the data streams ultimately planned for AWIPS. This initiated the next phase of upgrade for the Gateway.


To accomplish this next upgrade, the Gateway began plans for relocation from Suitland, Maryland, to a newly built Metro Center II building in Silver Spring, Maryland. The connection to NMC was changed from disk sharing to an File Transfer Protocol (FTP) file transfer bridge in 1989 between the two different operating systems, as the NMC was MVS and the Gateway was VM/SP. The move also required the installation of new hardware. The consolidation of the SMCC, Gateway, NOAA message center and Communications Control Center (CCC) in one facility on the sixth floor of the new building was accomplished. The NWSTG was relocated.

nws gateway facility in silver spring

gateway facility in silver spring

The Gateway moved from the IBM 4341 computers to HDS 9060 mainframes in Silver Spring, Maryland. The move was accomplished in July 1992 after the installation of a newly purchased AMDHAL 4745 in 1991 to replace the IBM 3705 and 3725 communication controllers left behind at Suitland, Maryland, along with the IBM 4341's. At this time all lines were bridged between Suitland and Silver Spring and new DataSwitch, Incorporated line switching equipment was installed at the CCC.

The new Gateway of 1992 had three HDS 9060 mainframes, three strings of HDS 7380 disks, and two strings of IBM 3375 disk drives. The communications controllers were an AMDHAL 4745, two Concurrent 3210 computers, and a CNT-CTC devices with T-1 lines for the connection between NMC in Suitland and the Gateway in Silver Spring. A LAN connection was established for TELNET access for the World Weather Building for use in reestablishing their console connection to the Gateway host system. Increased data storage needs required additional disk storage, and new EMC2 RAID storage technology disk units were installed in 1993. The international circuits to Buenos Aires and Brasilia were upgraded to X.25 protocol at 9600 bps in 1994, and the link to Tinker Air Force Base, Oklahoma, (relocated from Carswell Air Force Base, Texas, in 1993) was upgraded to using the X.25 protocol in 1994 operating at 19200 bps.


The Gateway added to its LAN technology in 1994 and introduced FTP file servers. This began a move to a client/server network centric architecture operation. Plans were being made in the middle of 1994 to design the Gateway with extensive downsizing of a mainframe architecture to a distributed operations on a high-speed backbone LAN. This change along with the addition of UNIX-based operating systems and file sharing devices, gives the Gateway more flexibility for interfacing with newer communication technologies.

By late 1994, the Gateway had added two new IBM RISC 6000's, a CISCO 7000 router, and a FDDI Backbone. New file servers supporting FTP, HTTP, and Gopher software were installed, and large amounts of data were made available at the Gateway on file servers. This permitted servers to establish a connection using the Internet. This established a standard means for data retrieval of documentation information using Internet browsers and retrieving meteorological and hydrological data interactively. The access to the data passing through the Gateway was now available using standard access methods on any client. The NWS Home Page and other documentation was made available in early 1995. The forecast offices began accessing large amounts of NMC model products using FTP over T-1 TCP/IP and Frame Relay links in 1995.


The first 50 years of the Gateway (1945 -1995) saw the growth from a small data collection room in Washington to a large computer facility in Suitland MD. The Gateway began by using the teletype paper tape for supplying information for hand plotted charts and ended as a highly automated switching system processing millions of data characters per day for switching between local forecast offices and among foreign centers and distributing model products both nationally and internationally.


The third upgrade began to take place in mid 1995. The selection process resulted in the purchase of an IBM 9673-R32 CMOS switching engine and LAN based processors for data processing and a new data base was developed using Sybase SQL architecture in early 1996. A first IBM 9673-R32 system was delivered in October 1996. New communications with NCEP and the DoD were installed in advance of the Gateway hardware upgrade. The NCEP moved operations in 1996 to the UNIX platform on Cray computers and the FTP protocol was used between the Gateway and NCEP on an new 10 mbps FNS using Ethernet protocol between routers. This process by NCEP removed their HDS 9080s and the MVS operations stopped production by early 1997. The DoD connection was upgraded to ATM for NWS to DoD sites of AFGWC and FNMOC in 1996. The Gateway started the NCEP DBnet transfer of files from the NCEP site to Gateway local file servers for use by the NWS field sites directly connected to the Gateway routers by November 1996.

The operational Gateway IBM 9672-RB4 system and backup system were installed October 1997 and made operational in January 1998. The Gateway HDS 9060s were removed in Early February 1998. The LAN Website was upgraded and moved to IBM 6000/F50 processors in April through July 1998 and the OSO File Server was upgraded on IBM 6000/H50 systems to meet the needs of additional capacity in July 1998. The final Gateway installation of central switching engine and LAN based processors combination was in place by July 1998.

- Top of Page -

Publication of the National Oceanic & Atmospheric Administration (NOAA), NOAA Central Library.

Last Updated: June 8, 2006 9:24 AM

Privacy Policy | Disclaimer