Weather Service Modernization: Risks Remain That Full Systems Potential
Will Not be Achieved (Testimony, 04/24/97, GAO/T-AIMD-97-85).
GAO discussed the National Weather Service's (NWS) systems modernization
program.
GAO noted that: (1) to reach the goal of better forecasting and earlier
warnings with a smaller, downsized operation, the Weather Service has
been acquiring new observing systems, including radars, satellites, and
ground-based sensors, as well as powerful forecaster workstations; (2)
the Advanced Weather Interactive Processing System (AWIPS) integrates,
for the first time, satellite, radar, and other data to support weather
forecaster decision-making and communications, and it is the linchpin of
the NWS modernization; (3) operating under a $550-million funding cap,
the system is expected to be fully deployed in 1999; (4) AWIPS
development systems have been delivered to 16 locations nationwide,
which this represents the first two of six modules, or "builds"; (5)
AWIPS is planned for a total of 152 locations once fully deployed; (6)
the Next Generation Geostationary Operational Environmental Satellite is
a program to acquire, launch, and control five satellites for
identifying and tracking severe weather events, such as hurricanes; (7)
the first satellite was launched in 1994, and the second in 1995; (8)
three more satellites are planned for launch between now and 2002; (9)
the Next Generation Weather Radar (NEXRAD) is a program to acquire 163
Doppler radars; (10) scheduled for completion this year, 121 of the
planned 123 NWS NEXRAD radars have been delivered to operational
locations; (11) the Automated Surface Observing System (ASOS) is a
program to automate and enhance methods for collecting, processing, and
displaying surface weather conditions, such as temperature and
precipitation, and to replace human weather observers; (12) scheduled
for completion in fiscal year 1998, the ASOS system has been installed
at 265 of the 314 planned NWS operational locations; (13) the Weather
Service has generated better data, particularly with the new radars and
satellites, and greatly improved forecasts and warnings; (14)
notwithstanding such successes, however, each of the four programs has
experienced cost increases and schedule delays; and (15) some of these
delays can be attributed to changes in requirements; others were caused
by program management and development problems.
--------------------------- Indexing Terms -----------------------------
REPORTNUM: T-AIMD-97-85
TITLE: Weather Service Modernization: Risks Remain That Full
Systems Potential Will Not be Achieved
DATE: 04/24/97
SUBJECT: Weather forecasting
Earth resources satellites
Systems conversions
Systems design
Requirements definition
Computer software verification and validation
Storms
Strategic information systems planning
IDENTIFIER: NWS Advanced Weather Interactive Processing System
NWS Next Generation Weather Radar
NWS Automated Surface Observing System
NOAA Geostationary Operational Environmental Satellite
GAO High Risk Program
NOAA/NASA GOES-Next Satellite Program
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Cover
================================================================ COVER
Before the Subcommittee on Oversight of Government Management,
Restructuring and the District of Columbia, Committee on Governmental
Affairs, U.S. Senate
For Release on Delivery
Expected at
12:30 p.m.
Thursday,
April 24, 1997
WEATHER SERVICE MODERNIZATION -
RISKS REMAIN THAT FULL SYSTEMS
POTENTIAL WILL NOT
BE ACHIEVED
Statement of Joel C. Willemssen
Director, Information Resources Management
Accounting and Information Management Division
GAO/T-AIMD-97-85
GAO/AIMD-97-85T
(511425)
Abbreviations
=============================================================== ABBREV
ASOS - Automated Surface Observing System
AWIPS - Advanced Weather Interactive Processing System
FSL - Forecast Systems Library
GOES - geostationary operational environmental satellite
GOES-Next - Next Generation Geostationary Operational Environmental
Satellite
NEXRAD - Next Generation Weather Radar
NOAA - National Oceanic and Atmospheric Administration
NWS - National Weather Service
WFO - Weather Forecast Office
============================================================ Chapter 0
Mr. Chairman and Members of the Subcommittee:
We are pleased to be here today to discuss the National Weather
Service's (NWS) systems modernization program. At an estimated cost
of about $4.5 billion, it is one of the largest modernization
programs in the federal government. The modernization is vital to
the Weather Service's plans for improving operations; at the same
time, it is intended to help NWS streamline and downsize its
organization, and is an effort that we continue to endorse. As with
most large systems-development projects, however, this program faces
persistent challenges that must be overcome if the considerable
anticipated benefits of full modernization are to be realized. Our
concerns led us to place the Weather Service effort on our 1995 list
of high-risk government programs, where it remains today.\1
The work of the National Weather Service is critically important to
all Americans, as the United States experiences considerable severe
weather. In a typical year, the United States is pummeled by about
10,000 violent thunderstorms; 5,000 floods; 1,000 tornadoes; and
several hurricanes. As we have seen in recent months, unpredictable
weather can wreak havoc in people's lives; sometimes the difference
between tragedy and recoverable loss lies in the ability of early
forecasts and warnings of potentially dangerous weather to help
protect life and property.
--------------------
\1 High-Risk Series: An Overview (GAO/HR-95-1, February 1995) and
High-Risk Series: Information Management and Technology
(GAO/HR-97-9, February 1997).
BACKGROUND
---------------------------------------------------------- Chapter 0:1
NWS uses a variety of systems and manual processes to collect,
process, and disseminate weather data to and among its network of
field offices and regional and national centers. Prior to the
modernization, these systems and processes were largely outdated.
Radar equipment dated back to the 1950s, and much of the current
information processing, display, and data communications system has
been in use since the 1970s.
To enhance its ability to deliver weather services, NWS determined
some 15 years ago to use the power of technology to "do more with
less." To reach the goal of better forecasting and earlier warnings
with a smaller, downsized operation, the Weather Service has been
acquiring new observing systems--including radars, satellites, and
ground-based sensors--as well as powerful forecaster workstations.
The goals of the modernization were to (1) achieve more uniform
weather services nationwide, (2) improve forecasting, (3) provide
more reliable detection and prediction of severe weather and
flooding, (4) permit more cost-effective operations, and (5) achieve
higher productivity. The modernization includes four major
systems-development programs, which I will briefly describe.
THE ADVANCED WEATHER
INTERACTIVE PROCESSING
SYSTEM (AWIPS)
-------------------------------------------------------- Chapter 0:1.1
This program integrates, for the first time, satellite, radar, and
other data to support weather forecaster decision-making and
communications; it is the linchpin of the NWS modernization.
Operating under a $550-million funding cap, the system is expected to
be fully deployed in 1999. AWIPS development systems have been
delivered to 16 locations nationwide; this represents the first two
of six modules, or "builds." AWIPS is planned for a total of 152
locations once fully deployed.
THE NEXT GENERATION
GEOSTATIONARY OPERATIONAL
ENVIRONMENTAL SATELLITE
(GOES-NEXT)
-------------------------------------------------------- Chapter 0:1.2
This is a program to acquire, launch, and control five satellites for
identifying and tracking severe weather events, such as hurricanes.
The first satellite was launched in 1994, and the second in 1995.
Three more satellites are planned for launch between now and 2002.
The total cost for these five satellites is estimated to be just
under $2 billion.
THE NEXT GENERATION WEATHER
RADAR (NEXRAD)
-------------------------------------------------------- Chapter 0:1.3
This is a program to acquire 163 Doppler radars.\2 Largely deployed,
these radars have helped NWS increase the accuracy and timeliness of
warnings for severe thunderstorms, tornadoes, and other hazardous
weather events. Scheduled for completion this year, 121 of a planned
123 NWS NEXRAD radars have been delivered to operational locations.
The cost of this program is just under $1.5 billion.
--------------------
\2 This includes radars for NWS, the Air Force, and the Federal
Aviation Administration.
THE AUTOMATED SURFACE
OBSERVING SYSTEM (ASOS)
-------------------------------------------------------- Chapter 0:1.4
This is a program to automate and enhance methods for collecting,
processing, and displaying surface weather conditions, such as
temperature and precipitation, and to replace human weather
observers. Scheduled for completion in fiscal year 1998, the system
has been installed at 265 of 314 planned NWS operational locations.
Estimated costs for ASOS are about $351 million; this includes the
NWS units and 554 units for the Federal Aviation Administration and
the Department of Defense.
The modernization also includes upgrades to existing systems,
improved weather models, and the acquisition of several smaller
systems. In addition, NWS is restructuring its field offices to be
more efficient; table 1 indicates the before-and-after plan.
Table 1
NWS Office Restructuring Plan
Pre-modernization Future
---------------------------------- ----------------------------------
52 Weather Service Forecast 119 Weather Forecast Offices\a
Offices
204 Weather Service Offices
3 National Centers 9 National Centers
13 River Forecast Centers 13 River Forecast Centers\a
----------------------------------------------------------------------
\a These offices are to be co-located.
Source: NWS.
IMPORTANT SUCCESSES ACHIEVED,
YET PROBLEMS HAVE HINDERED THE
MODERNIZATION
---------------------------------------------------------- Chapter 0:2
The Weather Service has generated better data--particularly with the
new radars and satellites--and greatly improved forecasts and
warnings. These can be related directly to saving lives and reducing
the effects of natural disasters. As shown in figure 1, lead times
of warnings for severe storms and tornadoes improved by about 5
minutes between 1986 and 1996, which is not insignificant. With
tornadoes, for example, it can mean the difference in whether people
have time to reach shelter. In some instances, lead times are much
earlier. Last year, for instance, NWS issued flood potential
"statements" 2-3 days in advance of Hurricane Fran. Flash flood
warnings were issued with 6 hours' lead time. Similarly, in the East
Coast blizzard of 1996, NWS issued forecasts 3 to 5 days in advance.
Figure 1: NWS Warning Lead
Time for Severe Local Storms,
1986-1996 (in minutes)
(See figure in printed
edition.)
Source: NWS.
Notwithstanding such successes, however, each of the four programs
has experienced cost increases and schedule delays.\3 Some of these
increases and delays can be attributed to changes in requirements;
others were caused by program management and development problems.
We reported in 1995 that six of eight sensors in the ASOS system did
not meet contract specifications for accuracy or performance. For
example, the precipitation accumulation sensor underreported rainfall
amounts during heavy downpours, and the temperature and dew point
sensor readings frequently fell short of dew point reliability
requirements. Some of these shortfalls occurred because of the
contractor's failure to deliver products that met specifications, and
others resulted from the failure of government-furnished equipment to
meet specifications. In addition, we found that ASOS users from the
aviation, meteorology, and climate communities had needs that the
ASOS system, as specified, did not satisfy.
We recommended that NWS define and prioritize--in conjunction with
ASOS users--all system corrections, enhancements, and supplements
necessary to meet valid user needs. We further recommended that NWS
formulate--again in conjunction with ASOS users--explicit system
performance and cost/benefit criteria governing the release of human
observers. Because of these problems, NWS delayed plans for
releasing human weather observers and implemented actions to correct
shortfalls in meeting specifications and to address other user
concerns.
In reference to NEXRAD, we testified in 1995 that many NWS and Air
Force radars were not available nearly as often as required. For
example, between 10 and 62 percent of Air Force NEXRAD radars were
falling short of availability requirements. (NWS did not know if its
radars were meeting the availability requirement because it was not
monitoring availability on a site-by-site basis.) Further, we found
that a radar upgrade to address one cause of unavailability--the lack
of an uninterruptible power supply--was not to be completed until
fiscal years 1999 and 2002 for the Air Force and NWS, respectively.
We recommended that NWS analyze and monitor system availability data
on a site-specific basis for operational NEXRADs and correct any
shortfalls in system availability revealed by the analysis. We also
recommended that the Air Force improve the reliability of Air Force
NEXRAD availability data and correct any shortfalls found. NWS and
the Air Force did initiate steps in 1995 to implement our
recommendations to improve NEXRAD availability.
In terms of staffing, the sizable reductions promised as a result of
the modernization will not be realized. While NWS originally planned
to reduce staff by 21 percent, we reported in 1995 that the goal had
been scaled back to 8 percent. NWS attributes the reduced goal
primarily to the need for more staff than originally envisioned to
operate new systems, and to other unanticipated requirements.
--------------------
\3 A list of related GAO reports and testimony on the NWS
modernization, including its four primary components, appears at the
end of this statement.
REMAINING RISKS
---------------------------------------------------------- Chapter 0:3
Mr. Chairman, the National Oceanic and Atmospheric Administration's
(NOAA) ultimate success in completing the modernization depends, in
part, on how well and how quickly it can complete a systems
architecture\4 and address specific risks associated with the crucial
AWIPS system. The modernization needs an overall architecture to
guide systems development; NWS agrees that such a technical blueprint
is necessary, and is currently working on one. Yet until such an
architecture is developed and enforced, the modernization will likely
continue to be subject to higher costs and reduced performance. This
is an important point as component systems continue to evolve to meet
additional demands and take advantage of improved technology. We
cannot emphasize too strongly the need for an overall architecture to
guide system evolution. An architecture would help ensure that
changes to NEXRAD, for example, are compatible with the many systems
with which NEXRAD must exchange data.
As we have reported several times over the past few years, full
utilization of the data from the new observing systems has been
prevented by delays and continuing problems with AWIPS. We have made
several recommendations that we feel will strengthen the Weather
Service's ability to acquire AWIPS. First, we recommended that NWS
ensure that each "build" is fully tested and all material defects
corrected before beginning software development associated with the
next build. Second, we recommended that NWS establish a software
quality assurance program to increase the probability of delivering
promised AWIPS capability on time and within budget. Third, we
recommended that NWS obtain an independent assessment of the cost to
develop and deploy AWIPS.
Progress to date in these areas has, however, been uneven, and we
remain concerned about AWIPS development risks--risks that threaten
the system's ability to be completed on time, within budget, and with
the functional capability that AWIPS must be able to provide. Until
AWIPS is deployed and functioning properly, NWS will not be able to
take full advantage of the nearly $4 billion investment it has made
in the other components of the modernization.
After early successes in demonstrating the technical feasibility of
system functions, design problems and disagreements between NOAA and
the development contractor in 1993-1994 stymied progress. Some
development responsibility was brought in-house--to NWS/NOAA labs--in
1995. The AWIPS program strategy was changed again in 1996, when
even more development responsibility--for AWIPS data acceptance,
processing, and display capabilities--was brought in-house, primarily
to NOAA's Forecast Systems Laboratory (FSL). At that time, NWS
decided to use FSL's prototype system, called Weather Forecast Office
(WFO)-Advanced, which was being developed in parallel with AWIPS as a
risk-reduction tactic.
NWS officials chose WFO-Advanced because of its demonstrated superior
data- acceptance, processing, and display capability over the
contractor's version, hoping that it would enable the agency to
deploy these AWIPS capabilities to field operations more quickly.
The contractor did, however, retain responsibility for
communications, system monitoring and control, and other
capabilities. With these changes, NWS expects AWIPS to make its 1999
target date for full deployment, within the $550-million cap.
As we reported in December 1994, NOAA/NWS labs are research and
development operations that primarily develop prototype systems; as
such, they did not employ software development processes
characteristic of a software-production environment. Specifically,
the labs did not have the software quality assurance and
configuration management processes, among others, sufficient to
ensure production of stable, reliable software code.\5 Developing
software code for use in one or two prototype installations requires
a far less rigorous approach than what is needed when nationwide
deployment is planned. However, some of the software the NOAA/NWS
labs were developing was intended for operational use in AWIPS and
was essentially being handed off directly from the labs to the
contractor. We therefore recommended that NWS and NOAA strengthen
their processes for developing production-quality software code.
With the 1995 and 1996 AWIPS development changes, significantly more
design and development responsibility has been transferred to the
government, in particular to NOAA's FSL. In visiting FSL in Boulder,
Colorado, we found that--with the exception of one subsystem that we
specifically discussed in 1994--the question of capability remained:
lab quality assurance and configuration management processes for
production-level software were still lacking. However, NWS and NOAA
officials said that they have heeded our 1994 recommendations and are
improving their processes in other ways. They said that in order to
preserve the labs' research and development missions, they do not
wish to impose any unnecessary, rigorous software development
procedures on the labs. Instead, NOAA management plans to play a
more active role in preparing the government-furnished software for
the contractor.
According to NWS officials, they plan to improve the software
development processes for WFO-Advanced and other government-developed
software using staff from NWS headquarters, NOAA's systems
acquisitions division, and the contractor. Specifically, NWS plans
to (1) more fully document the lab's design and software code, (2)
design the integration of government-furnished software and
contractor-developed software, (3) fully test all government software
before it is turned over to the contractor, and (4) strengthen
quality assurance and configuration management. To help accomplish
this, NWS has established several specific contract task orders.
Weather Service officials acknowledge that preparing WFO-Advanced for
the contractor is a large task because it comprises such a
significant portion of the AWIPS software. In addition, officials
understand that there is no room for schedule delays due to
unforeseen problems. They feel confident, however, that they can
meet this challenge because of the steps I have just described, and
because they have experience in turning government software over to a
contractor. For example, NWS' Office of Hydrology provided
hydro-meteorological software to the contractor for the first AWIPS
module ("build 1"), which was successfully tested last summer. In
addition, NWS officials said that they are applying to AWIPS lessons
learned from their configuration management experiences in the NEXRAD
and ASOS development projects.
NOAA has put into place appropriate plans and procedures to mitigate
these risks; how it implements these plans and procedures will be
critical if NOAA is to avoid turning the risks into actual problems.
Unfortunately, systems development risks in large projects such as
AWIPS frequently do turn into problems. And, as discussed, AWIPS has
suffered development setbacks in the past. Given these
circumstances, we believe it will be extremely difficult for NOAA and
NWS to develop and deploy the AWIPS system within the $550-million
cap.
What can be done to minimize such risks? First, NOAA and NWS
management need to be vigilant to identify new problems with AWIPS
software development. New software and WFO-Advanced must be fully
tested to ensure that they are up to production quality and will not
cause complications when integrated with other AWIPS software.
Second, we believe that NOAA needs to renegotiate as quickly as
possible the contract for AWIPS builds 4 through 6. While NOAA
officials expect no major cost or schedule changes, this is not a
guarantee; NOAA must exercise close oversight of this process.
--------------------
\4 A systems architecture is a blueprint to guide and constrain the
development and evolution (i.e., maintenance) of a collection of
related systems; it can be viewed as having both logical and
technical components. At the logical level, the architecture
provides a high-level description of the organizational mission being
accomplished, the business functions being performed and the
relationships among functions, the information needed to perform the
functions, and the flow of information among functions. At the
technical level, the architecture provides the rules and standards
needed to ensure that the interrelated systems are built to be
interoperable, portable, and maintainable. These include
specifications of critical aspects of the component systems'
hardware, software, communications, data, security, and performance
characteristics.
\5 Software quality assurance refers to a program that independently
(1) monitors whether the software and the processes used to develop
it fully satisfy established standards and procedures and (2) ensures
that any deficiencies in the software product, process, or their
associated standards are swiftly brought to management's attention.
Software configuration management refers to a process by which
changes to software products are controlled. It includes
identification of products to be controlled, accounting for changes
to these products, and reporting on the products' status.
GEOSTATIONARY OPERATIONAL
ENVIRONMENTAL SATELLITE (GOES)
---------------------------------------------------------- Chapter 0:4
Another important element of the Weather Service modernization is the
acquisition of geostationary operational environmental satellites
(GOES). These satellites are uniquely positioned to be able to
observe the development of severe weather, such as hurricanes and
thunderstorms, and provide information allowing forecasters to issue
timely warnings. Satellites in the current series will, however,
begin to reach the end of their useful lives within 5 years; NOAA is
now planning to procure replacements, which will be very similar to
the current satellites. At issue, Mr. Chairman, is the type of
satellite system to build for the longer term, especially in light of
NOAA's budget, which is likely to remain constrained in the immediate
years ahead. Our report on both short- and long-term satellite
replacements was released last month.\6
In brief, we found NOAA's approach for the near term reasonable,
although we recommended that the agency clarify its policy for
replacing partially failed satellites and backing up planned
launches. For the longer term, we concluded that changing the GOES
system design offers many potential benefits: improved performance,
lower costs, and more closely meeting the needs of forecasters.
Several new approaches have been suggested in recent years, by
government, academic, and industry experts; many include technologies
unavailable when the present series of satellites was designed.
These approaches have pros and cons; all options would require
careful engineering analysis before an informed decision about the
future of the GOES program can be made.
Our concern centers on NOAA's delay in conducting such analyses and
developing specific proposals. At present, NOAA anticipates
beginning its follow-up program in 2003 at the earliest. Given that
developing a new satellite takes up to 10 years, deferring a start
until 2003 likely means that NOAA will have to rely on its current,
early-1980s-design satellites until about 2013.
Mr. Chairman, given the range of options that exist for a
significantly improved GOES system, the Congress may wish to evaluate
the costs and benefits of different approaches to the timing,
funding, and scope of the follow-up program. This could include a
potential role for the National Aeronautics and Space
Administration's advanced spacecraft technology programs.
In summary, we see clear benefits in the National Weather Service
modernization--improved forecasts and warnings. We also see
risks--risks that can only be reduced through development and
enforcement of a systems modernization architecture, careful
implementation of planned mitigation techniques in the case of AWIPS,
and commitment to earlier planning in the case of the GOES
satellites.
--------------------
\6 Weather Satellites: Planning for the Geostationary Satellite
Program Needs More Attention (GAO/AIMD-97-37, March 13, 1997).
-------------------------------------------------------- Chapter 0:4.1
This concludes my statement, Mr. Chairman. I would be happy to
respond to any questions you or other Members of the Subcommittee may
have at this time.
RELATED GAO PRODUCTS
=========================================================== Appendix 1
National Oceanic and Atmospheric Administration: Weather Service
Modernization and NOAA Corps Issues (GAO/T-AIMD/GGD-97-63, March 13,
1997).
Weather Satellites: Planning for the Geostationary Operational
Environmental Satellite Program Needs More Attention (GAO/AIMD-97-37,
March 13, 1997).
High-Risk Series: Information Management and Technology
(GAO/HR-97-9, February 1997).
NOAA Satellites (GAO/AIMD-96-141R, September 13, 1996).
Weather Forecasting: Recommendations to Address New Weather
Processing System Development Risks (GAO/AIMD-96-74, May 13, 1996).
Weather Forecasting: NWS Has Not Demonstrated that New Processing
System Will Improve Mission Effectiveness (GAO/AIMD-96-29, February
29, 1996).
Weather Forecasting: New Processing System Faces Uncertainties and
Risks (GAO/T-AIMD-96-47, February 29, 1996).
Weather Forecasting: Radars Far Superior to Predecessors, but
Location and Availability Questions Remain (GAO/T-AIMD-96-2, October
17, 1995).
Weather Service Modernization Staffing (GAO/AIMD-95-239R, September
26, 1995).
Weather Forecasting: Radar Availability Requirements Not Being Met
(GAO/AIMD-95-132, May 31, 1995).
Weather Forecasting: Unmet Needs and Unknown Costs Warrant
Reassessment of Observing System Plans (GAO/AIMD-95-81, April 21,
1995).
Weather Service Modernization Questions (GAO/AIMD-95-106R, March 10,
1995).
Weather Service Modernization: Despite Progress, Significant
Problems and Risks Remain (GAO/T-AIMD-95-87, February 21, 1995).
Meteorological Satellites (GAO/NSIAD-95-87R, February 6, 1995).
High-Risk Series: An Overview (GAO/HR-95-1, February 1995).
Weather Forecasting: Improvements Needed in Laboratory Software
Development Processes (GAO/AIMD-95-24, December 14, 1994).
Weather Forecasting: Systems Architecture Needed for National
Weather Service Modernization (GAO/AIMD-94-28, March 11, 1994).
Weather Forecasting: Important Issues on Automated Weather
Processing System Need Resolution (GAO/IMTEC-93-12BR, January 6,
1993).
Weather Satellites: Action Needed To Resolve Status of the U.S.
Geostationary Satellite Program (GAO/NSIAD-91-252, July 24, 1991).
Weather Satellites: Cost Growth and Development Delays Jeopardize
U.S. Forecasting Ability (GAO/NSIAD-89-169, June 30, 1989).
*** End of document. ***