Introduction
The aviation weather service program is a joint effort of the National Oceanic and Atmospheric Administration (NOAA), the Federal Aviation Administration (FAA), the Department of Defense (DOD), and commercial aviation weather providers.
National Oceanic and Atmospheric Administration (NOAA)
NOAA is an agency of the Department of Commerce (DOC). NOAA conducts research and gathers data about the global oceans, atmosphere, space, and Sun, and applies this knowledge to science and service, which touches the lives of all Americans. Among its six major divisions are the National Environmental Satellite, Data, and Information Service (NESDIS) and the NWS.
National Environmental Satellite, Data, and Information Service (NESDIS)
NESDIS manages the U.S. civil operational remote-sensing satellite systems, as well as other global information for meteorology, oceanography, solid-earth geophysics, and solar-terrestrial sciences. NESDIS provides this data to NWS meteorologists and a wide range of other users for operational weather forecasting.
Satellite Analysis Branch (SAB)
NESDIS’ Satellite Analysis Branch (SAB) serves as the operational focal point for real-time imagery products and multidisciplinary environmental analyses. The SAB’s primary mission is to support disaster mitigation and warning services for the U.S. Federal agencies and the international community. Routine environmental analyses are provided to forecasters and other environmental users, and are used in the numerical models of the NWS. The SAB schedules and distributes real-time satellite imagery products from global geostationary and polar-orbiting satellites to environmental users.
The SAB coordinates the satellite and other information for the NOAA Volcanic Hazards Alert Program, under an agreement with the FAA, and works with the NWS as part of the Washington, DC, Volcanic Ash Advisory Center (VAAC). The Washington, DC, VAAC area of responsibility stretches from 40° W to 130° E and includes the areas of the contiguous United States (CONUS), New York and Oakland Oceanic Flight Information Regions (FIR), and southward through Central America and the Caribbean to 10° S in South America.
National Weather Service (NWS)
The NWS provides weather data, forecasts, and warnings for the United States, its territories, adjacent waters, and ocean areas for the protection of life and property and the enhancement of the national economy. NWS data and products form a national information database and infrastructure that can be used by other government agencies, the private sector, the public, and the global community. The following sections provide a description of NWS offices associated with aviation weather.
National Centers for Environmental Prediction (NCEP)
The National Centers for Environmental Prediction (NCEP) is where virtually all global meteorological data is collected and analyzed for the United States. The NCEP then provides a wide variety of national and international weather guidance products to NWS field offices, government agencies, emergency managers, and private sector meteorologists. The NCEP is a critical resource in national and global weather prediction and is the starting point for nearly all weather forecasts in the United States.
The NCEP is comprised of nine distinct centers and the Office of the Director. Each center has its own specific mission. The following NCEP centers provide aviation weather products and services.
NCEP Central Operations (NCO)
The NCEP Central Operations (NCO) in College Park, MD, sustains and executes the operational suite of the numerical analysis and forecast models and prepares NCEP products for dissemination. It also links all nine of the national centers together via computer and communications-related services.
Aviation Weather Center (AWC)
The Aviation Weather Center (AWC) in Kansas City, MO, issues a suite of aviation weather forecasts in support of the National Airspace System (NAS) that are described in this handbook, including Airmen’s Meteorological Information (AIRMET), Significant Meteorological Information (SIGMET), Convective SIGMETs, and various icing, turbulence, and convective forecast products. The AWC is a Meteorological Watch Office (MWO) for the International Civil Aviation Organization (ICAO). The AWC, in conjunction with the NCO, also serves as one of two ICAO World Area Forecast Centers (WAFC), known as WAFC Washington, issuing flight planning data (winds and temperatures) and Significant Weather (SIGWX) forecasts.
The AWC’s website provides the aviation community with textual, digital, and graphical forecasts, analyses, and observations of aviation-related weather variables. Additionally, the website provides information for international flights through the World Area Forecast System (WAFS) Internet File Service (WIFS).
Weather Prediction Center (WPC)
The Weather Prediction Center (WPC) in College Park, MD, provides analysis and forecast products specializing in multiday, quantitative precipitation forecasts and weather forecast guidance, weather model diagnostics discussions, and surface pressure and frontal analyses.
Storm Prediction Center (SPC)
The Storm Prediction Center (SPC) in Norman, OK, provides tornado and severe weather watches for the CONUS along with a suite of hazardous weather forecasts.
National Hurricane Center (NHC)
The National Hurricane Center (NHC) in Miami, FL, provides official NWS forecasts of the movement and strength of tropical weather systems and issues the appropriate watches and warnings for the CONUS and surrounding areas. It also issues a suite of marine products covering the tropical Atlantic, Caribbean, Gulf of Mexico, and tropical eastern Pacific. In support of ICAO, the NHC is also referred to as a Tropical Cyclone Advisory Center (TCAC).
Space Weather Prediction Center (SWPC)
The Space Weather Prediction Center (SWPC) in Boulder, CO, provides space weather information (e.g., current activity and forecasts) to a wide variety of users. The SWPC is also an ICAO Space Weather Center and is responsible for issuing global advisories for space weather events affecting communication and navigation systems as well as events that pose a potential health hazard to passengers and crew.
Alaska Aviation Weather Unit (AAWU)
The Alaska Aviation Weather Unit (AAWU), located in Anchorage, AK, is an MWO for ICAO. The AAWU is responsible for the entire Anchorage FIR. They issue a suite of aviation weather products for the airspace over Alaska and adjacent coastal waters, including AIRMETs, SIGMETs, FAs, and SIGWX Prognostic Charts.
The AAWU is also designated as the Anchorage VAAC. The VAAC area of responsibility includes the Anchorage FIR and Far Eastern Russia and is responsible for the issuance of Volcanic Ash Advisories (VAA).
Center Weather Service Unit (CWSU)
Center Weather Service Units (CWSU) are units of NWS meteorologists under contract with the FAA that are stationed at, and support, the FAA’s air route traffic control center (ARTCC).
CWSUs provide timely weather consultation, forecasts, and advice to managers within ARTCCs and to other supported FAA facilities.
Special emphasis is given to those weather conditions that are hazardous to aviation or that could impede the flow of air traffic within the NAS. CWSU meteorologists issue the following products in support of their respective ARTCC: Center Weather Advisories (CWA) and Meteorological Impact Statements (MIS).
Weather Forecast Office (WFO)
The NWS has 122 Weather Forecast Offices (WFO) across the United States and select territories. An NWS WFO is a multipurpose, local weather forecast center that produces, among its suite of services, aviationrelated products. In support of aviation, WFOs issue Terminal Aerodrome Forecasts (TAF) and Aviation Forecast Discussions (AFD), with some offices issuing Airport Weather Warnings (AWW), Soaring Forecasts, and Balloon Forecasts. The WFO also issues weather warnings such as tornado and severe thunderstorm warnings.
The Honolulu WFO is unique among NWS WFOs in that it provides multiple services beyond the typical WFO. WFO Honolulu is also designated as an MWO for ICAO. As a result of this unique designation,
WFO Honolulu is the only WFO to issue the following text products: AIRMETs and SIGMETs. WFO Honolulu is co-located with the Central Pacific Hurricane Center (CPHC). The CPHC provides official NWS forecast of the movement and strength of tropical weather systems and issues the appropriate watches and warnings for the central Pacific, including the State of Hawaii. WFO Honolulu also issues a suite of marine products covering a large portion of the Pacific Ocean. In support of ICAO, the CPHC is also referred to as a TCAC.
Federal Aviation Administration (FAA)
The FAA, a part of the Department of Transportation (DOT), provides a safe, secure, and efficient airspace system for the promotion of U.S. aerospace safety.
Per Title 49 of the United States Code (49 U.S.C.) § 44720, Meteorological Services, the FAA establishes all requirements for aviation weather reports and forecasts.
The FAA provides a wide range of services to the aviation community. The following sections provide a description of those FAA facilities that are involved with aviation weather and pilot services.
Air Traffic Control Systems Command Center (ATCSCC)
The air traffic control systems command center (ATCSCC) has the mission of balancing air traffic demand with system capacity. This ensures maximum safety and efficiency for the NAS, while minimizing delays. The ATCSCC utilizes the Traffic Management System (TMS), aircraft situation display, monitor alert, follow-on functions, and direct contact with ARTCC and Terminal Radar Approach Control (TRACON) facility Traffic Management Units (TMU) to manage flow on a national level.
Because weather is the most common reason for air traffic delays and reroutings, NWS meteorologists support the ATCSCC. These meteorologists, called National Aviation Meteorologists, coordinate NWS operations in support of traffic flow management within the NAS.
Air Route Traffic Control Center (ARTCC)
An ARTCC is a facility established to provide air traffic control (ATC) service to pilots operating on instrument flight rules (IFR) flight plans within controlled airspace, principally during the en route phase of flight. When equipment capabilities and controller workload permit, certain advisory/assistance services may be provided to pilots operating under visual flight rules (VFR).
En route controllers become familiar with pertinent weather information and stay aware of current weather information needed to perform ATC duties. En route controllers advise pilots of hazardous weather that may impact operations within 150 nautical miles (NM) of the controller’s assigned sector or jurisdiction and may solicit Pilot Weather Reports (PIREP) from pilots.
Airport Traffic Control Tower (ATCT) and Terminal Radar Approach Control (TRACON)
An airport traffic control tower (ATCT) is a terminal facility that uses air-to-ground communications, visual signaling, and other devices to provide ATC services to aircraft operating in the vicinity of an airport or on the movement area.
Terminal controllers become familiar with pertinent weather information and stay aware of current weather information needed to perform ATC duties. Terminal controllers advise pilots of hazardous weather that may impact operations within 150 NM of the controller’s assigned sector or area of jurisdiction and may solicit PIREPs from pilots. ATCTs and TRACONs may opt to broadcast hazardous weather information alerts only when any part of the area described is within 50 NM of the airspace under the ATCT’s jurisdiction.
Flight Service
The FAA delivers flight services to pilots in the CONUS, Alaska, Hawaii, and Puerto Rico. Services are provided by phone at 1-800-WX-BRIEF, on the internet through the Flight Service Pilot Web Portal (which can be found in Appendix G, Websites), and in person (Alaska only) at 17 Flight Service Stations (FSS). Services include, but are not limited to: preflight weather briefings, flight planning, and in-flight advisory services.
FAA Weather Camera Program
Flight Service also delivers the FAA’s Aviation Weather Camera Network. It features an expanding network of camera sites in Alaska, Hawaii, and the CONUS. Weather cameras provide pilots in certain areas with snapshots of current conditions at a specific location, enabling pilots to have additional information for improved decision making. Services may be obtained by visiting the Aviation Weather Cameras website, which can be found in Appendix A. See Section 3.3.3.2 and Section 24.9 for additional information.
Department of Defense (DOD)
The DOD is a key partner with the FAA and NWS in the next generation weather radar (NEXRAD) program. Various branches of the DOD provide their own weather support, but this is beyond the scope of this handbook.
Commercial Weather Information Providers
Commercial weather information providers are a major source of weather products for the aviation community. In general, they produce proprietary weather products based on NWS information with formatting and layout modifications, but no material changes to the weather information itself. This is also referred to as “repackaging.” Commercial providers also produce forecasts, analyses, and other proprietary weather products, which may substantially differ from the information contained in NWS-produced products. Operators who desire to use products prepared by a commercial weather provider should consult the Aeronautical Information Manual (AIM), Chapter 7, Section 1, Paragraph 7-1-3, Use of Aviation Weather Products, which provides additional information pertaining to commercial providers, including the Enhanced Weather Information System (EWINS).
