NWS is the nation’s official and authoritative source for watches and warnings during severe weather and is responsible for providing weather and climate data and issuing forecasts and warnings for the protection of life and property and enhancement of the national economy. Through its operational units nationwide, NWS issues many types of forecasts and warnings including weather, river, flood, and aviation. It issues approximately 1.5 million forecasts and 50,000 warnings annually. NWS also supports the national infrastructure that collects and processes worldwide weather data and climate observations from the air, land, and sea. This infrastructure includes technologies such as Doppler weather radar; satellites operated by NOAA’s National Environmental Satellite, Data, and Information Service; marine data buoys; surface observing systems; and instruments for monitoring space weather. Across this infrastructure, NWS collects billions of weather and climate observations annually, which are fed into its supercomputer forecasting models. In fiscal year 2016, NWS had 4,218 employees, of whom 3,629 were in operational units, and NOAA’s budget for NWS was approximately $1.1 billion, according to NWS documentation. NWS headquarters, led by the Director of NWS, is responsible for overall agency management, including overseeing operations and conducting budgetary formulation, analysis, and reporting. NWS’s Chief Operating Officer, based out of NWS’s headquarters, oversees six regional offices— referred to as regional headquarters—and the director’s office of the National Centers. NWS’s regional headquarters and the director’s office of the National Centers, in turn, oversee various local operational units. Together, these units constitute six categories of operational units, with a total of 168 individual operational units as follows. Regional headquarters. Six regional headquarters are led by regional directors who provide administrative and operational support, including managing the regions’ budgets and hiring efforts, to the following offices and centers: Weather forecast offices. One hundred and twenty-two offices operate 24 hours a day, 7 days a week, to monitor local weather and issue local forecasts and warnings. Weather service offices. Fifteen offices, mostly located in Alaska, operate on various schedules to collect weather observations that assist with the development of local, national, and global forecasts and warnings. River forecast centers. Thirteen centers operate 16 hours a day, 7 days a week, to monitor major river systems and aquifers to produce river and flood forecasts and coordinate warnings with local weather forecast offices. These centers increase their service hours as needed when flooding is predicted or is occurring. Tsunami warning centers. Two centers generally operate 24 hours a day, 7 days a week to monitor seismic and sea level activity and issue tsunami forecasts and warnings for the United States and its territories. National Centers and the director’s office. The director’s office of the National Centers oversees nine National Centers and provides them administrative and operational support, including managing their hiring efforts. The National Centers generate products and services to support other NWS operational units, as well as private sector partners, other governmental agencies, and the public. Most centers operate 24 hours a day, 7 days a week and some issue forecasts and warnings related to a particular area of focus (e.g., the National Hurricane Center issues forecasts and warnings for hurricanes and other tropical weather). The nine centers are the: (1) Aviation Weather Center, (2) Climate Prediction Center, (3) Environmental Modeling Center, (4) National Centers for Environmental Prediction Central Operations, (5) National Hurricane Center, (6) Ocean Prediction Center, (7) Space Weather Prediction Center, (8) Storm Prediction Center, and (9) Weather Prediction Center. Figure 1 shows the location of NWS’s six regions and 168 operational units. (App. II provides information on NWS’s 168 operational units by operational unit category and location.) The structure of NWS’s operational units is principally based on NWS’s efforts to modernize the agency during the 1990s. During the modernization effort, NWS established a standardized staffing model in its operational units to provide more uniform services. The staffing structure across NWS operational units is generally based on “fair weather” forecasting needs, meaning that additional staff and overtime may be called for to help with issuing weather forecasts and warnings during severe weather and emergency events. See figure 2 for examples of forecasting workstations at NWS operational units. As noted above, NWS receives support for certain administrative functions from NOAA’s WFMO, including workforce planning; hiring; and processing personnel actions such as promotions. WFMO also works with NOAA’s Office of Security—which is staffed and directed by the Department of Commerce’s Office of Security—to ensure security checks and background investigations are conducted as part of the hiring process, as necessary. Beginning in 2013, a series of events led to a hiring backlog at NWS. Specifically, in response to the 2013 federal budget sequestration, NOAA implemented an agency-wide hiring freeze. Because WFMO generally could not hire or replace departing employees during the freeze, the number of vacancies at NWS increased. According to WFMO officials, when the hiring freeze was lifted in 2014, demand for hiring across NOAA was high. Simultaneously, WFMO had experienced a high level of attrition during the freeze—in fiscal years 2013 and 2014, approximately 50 percent of WFMO staff handling hiring left the agency, according to a WFMO official—and therefore, WFMO could not keep pace with the hiring demand when the freeze was lifted. In fiscal year 2016, attrition at NWS outpaced WFMO’s hiring abilities. Over the course of the fiscal year, 191 staff left NWS, and WFMO hired 157 external candidates, according to WFMO data. Therefore, NWS’s hiring backlog increased. According to NWS documents and officials, NWS had resources to fill vacant operational unit positions, but it was unable to do so because of limited hiring resources at WFMO. According to NOAA budget officials, an administrative spending cap has limited WFMO’s ability to increase its hiring activities to address the hiring demand. In particular, since fiscal year 2005, NOAA has been subject to an administrative spending cap in its annual appropriation that places restrictions on the dollar amount the agency can spend for administrative support, including the amount it can spend on hiring actions. Additionally, in 2016, WFMO began planning changes to the hiring- related functions it provides to NWS. Specifically, NOAA began transitioning toward using a newly established Commerce-wide Enterprise Services Organization (ESO)—a shared services model—to process actions related to human capital, including hiring requests for NWS and NOAA’s other agencies. A NOAA official said that ESO is intended to improve operational efficiencies by increasing automation levels, streamlining business processes, and improving customer service. When ESO is fully established, WFMO officials said they anticipate that WFMO will provide business advisors to NWS to continue to provide workforce planning assistance, counseling on human capital issues, and other hiring-related assistance. Available NWS data show that vacancies at operational units increased from fiscal years 2010 through 2016. Specifically, we determined that across NWS’s 168 operational units, vacancies increased from about 5 percent (211 positions) at the end of fiscal year 2010, to about 11 percent (455 positions) at the end of fiscal year 2016. These vacancy rates are based on data from NWS’s organizational table, a database that tracks information on the number, type, and location of positions across the agency, including whether each position is filled. However, these vacancy rates do not factor in the agency’s available resources, according to NOAA and NWS officials. The officials explained that from fiscal years 2010 through 2016, NWS did not have resources to support all of the positions included in its organizational table. For example, in fiscal year 2016, an NWS official said that the organizational table contained approximately 185 more positions than the agency had resources to support. To address this issue, NWS developed additional vacancy data that factored in its available resources. Based on these data, the vacancy rate across operational units was approximately 0.6 percent in fiscal year 2010 and increased to about 7 percent in fiscal year 2016. NWS developed these data by proportionally distributing unfilled positions from the organizational table across the operational units to show the number of positions the agency had resources to fill at an agencywide level. However, while useful in providing an estimate of agencywide vacancies, these data do not reflect how individual NWS operational units have managed their staffing levels and vacancies. Instead of identifying specific positions on its organizational table to leave unfilled to ensure staffing levels did not exceed available agency resources, NWS established a “targeted vacancy rate” practice in 2014. Under this practice, the six NWS regional headquarters directors and the director of the National Centers are to hold approximately 5 percent of the positions on the organizational table vacant across their operational units. NWS headquarters officials said that the regional headquarters directors and the director of the National Centers are responsible for implementing this practice and have discretion to allocate resources according to their needs to achieve the agency’s mission goals. Most directors said that they have not had to manage to the targeted vacancy rate, however, because existing vacancies have kept staffing levels below what NWS resources can support. For vacancy rates at the operational unit level, we examined data from NWS’s organizational table and determined that vacancies have varied across NWS operational units, by category of operational unit, and by region. For example, at the close of fiscal year 2016, the vacancy rate across operational units was about 11 percent.