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Shun Liu
,
Geoff DiMego
,
Shucai Guan
,
V. Krishna Kumar
,
Dennis Keyser
,
Qin Xu
,
Kang Nai
,
Pengfei Zhang
,
Liping Liu
,
Jian Zhang
,
Kenneth Howard
, and
Jeff Ator

Abstract

Real-time access to level II radar data became available in May 2005 at the National Centers for Environmental Prediction (NCEP) Central Operations (NCO). Using these real-time data in operational data assimilation requires the data be processed reliably and efficiently through rigorous data quality controls. To this end, advanced radar data quality control techniques developed at the National Severe Storms Laboratory (NSSL) are combined into a comprehensive radar data processing system at NCEP. Techniques designed to create a high-resolution reflectivity mosaic developed at the NSSL are also adopted and installed within the NCEP radar data processing system to generate hourly 3D reflectivity mosaics and 2D-derived products. The processed radar radial velocity and 3D reflectivity mosaics are ingested into NCEP’s data assimilation systems to improve operational numerical weather predictions. The 3D reflectivity mosaics and 2D-derived products are also used for verification of high-resolution numerical weather prediction. The NCEP radar data processing system is described.

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Jian Zhang
,
Kenneth Howard
,
Carrie Langston
,
Steve Vasiloff
,
Brian Kaney
,
Ami Arthur
,
Suzanne Van Cooten
,
Kevin Kelleher
,
David Kitzmiller
,
Feng Ding
,
Dong-Jun Seo
,
Ernie Wells
, and
Chuck Dempsey

The National Mosaic and Multi-sensor QPE (Quantitative Precipitation Estimation), or “NMQ”, system was initially developed from a joint initiative between the National Oceanic and Atmospheric Administration's National Severe Storms Laboratory, the Federal Aviation Administration's Aviation Weather Research Program, and the Salt River Project. Further development has continued with additional support from the National Weather Service (NWS) Office of Hydrologic Development, the NWS Office of Climate, Water, and Weather Services, and the Central Weather Bureau of Taiwan. The objectives of NMQ research and development (R&D) are 1) to develop a hydrometeorological platform for assimilating different observational networks toward creating high spatial and temporal resolution multisensor QPEs for f lood warnings and water resource management and 2) to develop a seamless high-resolution national 3D grid of radar reflectivity for severe weather detection, data assimilation, numerical weather prediction model verification, and aviation product development.

Through about ten years of R&D, a real-time NMQ system has been implemented (http://nmq.ou.edu). Since June 2006, the system has been generating high-resolution 3D reflectivity mosaic grids (31 vertical levels) and a suite of severe weather and QPE products in real-time for the conterminous United States at a 1-km horizontal resolution and 2.5 minute update cycle. The experimental products are provided in real-time to end users ranging from government agencies, universities, research institutes, and the private sector and have been utilized in various meteorological, aviation, and hydrological applications. Further, a number of operational QPE products generated from different sensors (radar, gauge, satellite) and by human experts are ingested in the NMQ system and the experimental products are evaluated against the operational products as well as independent gauge observations in real time.

The NMQ is a fully automated system. It facilitates systematic evaluations and advances of hydrometeorological sciences and technologies in a real-time environment and serves as a test bed for rapid science-to-operation infusions. This paper describes scientific components of the NMQ system and presents initial evaluation results and future development plans of the system.

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David Parsons
,
Walter Dabberdt
,
Harold Cole
,
Terrence Hock
,
Charles Martin
,
Anne-Leslie Barrett
,
Erik Miller
,
Michael Spowart
,
Michael Howard
,
Warner Ecklund
,
David Carters
,
Kenneth Gage
, and
John Wilson

An Integrated Sounding System (ISS) that combines state-of-the-art remote and in situ sensors into a single transportable facility has been developed jointly by the National Center for Atmospheric Research (NCAR) and the Aeronomy Laboratory of the National Oceanic and Atmospheric Administration (NOAA/AL). The instrumentation for each ISS includes a 915-MHz wind profiler, a Radio Acoustic Sounding System (RASS), an Omega-based NAVAID sounding system, and an enhanced surface meteorological station. The general philosophy behind the ISS is that the integration of various measurement systems overcomes each system's respective limitations while taking advantage of its positive attributes. The individual observing systems within the ISS provide high-level data products to a central workstation that manages and integrates these measurements. The ISS software package performs a wide range of functions: real-time data acquisition, database support, and graphical displays; data archival and communications; and operational and posttime analysis. The first deployment of the ISS consists of six sites in the western tropical Pacific—four land-based deployments and two ship-based deployments. The sites serve the Coupled Ocean-Atmosphere Response Experiment (COARE) of the Tropical Ocean and Global Atmosphere (TOGA) program and TOGA's enhanced atmospheric monitoring effort. Examples of ISS data taken during this deployment are shown in order to demonstrate the capabilities of this new sounding system and to demonstrate the performance of these in situ and remote sensing instruments in a moist tropical environment. In particular, a strong convective outflow with a pronounced impact of the atmospheric boundary layer and heat fluxes from the ocean surface was examined with a shipboard ISS. If these strong outflows commonly occur, they may prove to be an important component of the surface energy budget of the western tropical Pacific.

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Phillip B. Chilson
,
Winifred F. Frick
,
Jeffrey F. Kelly
,
Kenneth W. Howard
,
Ronald P. Larkin
,
Robert H. Diehl
,
John K. Westbrook
,
T. Adam Kelly
, and
Thomas H. Kunz

Aeroecology is an emerging scientific discipline that integrates atmospheric science, Earth science, geography, ecology, computer science, computational biology, and engineering to further the understanding of biological patterns and processes. The unifying concept underlying this new transdisciplinary field of study is a focus on the planetary boundary layer and lower free atmosphere (i.e., the aerosphere), and the diversity of airborne organisms that inhabit and depend on the aerosphere for their existence. Here, we focus on the role of radars and radar networks in aeroecological studies. Radar systems scanning the atmosphere are primarily used to monitor weather conditions and track the location and movements of aircraft. However, radar echoes regularly contain signals from other sources, such as airborne birds, bats, and arthropods. We briefly discuss how radar observations can be and have been used to study a variety of airborne organisms and examine some of the many potential benefits likely to arise from radar aeroecology for meteorological and biological research over a wide range of spatial and temporal scales. Radar systems are becoming increasingly sophisticated with the advent of innovative signal processing and dual-polarimetric capabilities. These capabilities should be better harnessed to promote both meteorological and aeroecological research and to explore the interface between these two broad disciplines. We strongly encourage close collaboration among meteorologists, radar scientists, biologists, and others toward developing radar products that will contribute to a better understanding of airborne fauna.

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Jian Zhang
,
Kenneth Howard
,
Carrie Langston
,
Brian Kaney
,
Youcun Qi
,
Lin Tang
,
Heather Grams
,
Yadong Wang
,
Stephen Cocks
,
Steven Martinaitis
,
Ami Arthur
,
Karen Cooper
,
Jeff Brogden
, and
David Kitzmiller

Abstract

Rapid advancements of computer technologies in recent years made the real-time transferring and integration of high-volume, multisource data at a centralized location a possibility. The Multi-Radar Multi-Sensor (MRMS) system recently implemented at the National Centers for Environmental Prediction demonstrates such capabilities by integrating about 180 operational weather radars from the conterminous United States and Canada into a seamless national 3D radar mosaic with very high spatial (1 km) and temporal (2 min) resolution. The radar data can be integrated with high-resolution numerical weather prediction model data, satellite data, and lightning and rain gauge observations to generate a suite of severe weather and quantitative precipitation estimation (QPE) products. This paper provides an overview of the initial operating capabilities of MRMS QPE products.

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Jonathan J. Gourley
,
Zachary L. Flamig
,
Humberto Vergara
,
Pierre-Emmanuel Kirstetter
,
Robert A. Clark III
,
Elizabeth Argyle
,
Ami Arthur
,
Steven Martinaitis
,
Galateia Terti
,
Jessica M. Erlingis
,
Yang Hong
, and
Kenneth W. Howard

Abstract

This study introduces the Flooded Locations and Simulated Hydrographs (FLASH) project. FLASH is the first system to generate a suite of hydrometeorological products at flash flood scale in real-time across the conterminous United States, including rainfall average recurrence intervals, ratios of rainfall to flash flood guidance, and distributed hydrologic model–based discharge forecasts. The key aspects of the system are 1) precipitation forcing from the National Severe Storms Laboratory (NSSL)’s Multi-Radar Multi-Sensor (MRMS) system, 2) a computationally efficient distributed hydrologic modeling framework with sufficient representation of physical processes for flood prediction, 3) capability to provide forecasts at all grid points covered by radars without the requirement of model calibration, and 4) an open-access development platform, product display, and verification system for testing new ideas in a real-time demonstration environment and for fostering collaborations.

This study assesses the FLASH system’s ability to accurately simulate unit peak discharges over a 7-yr period in 1,643 unregulated gauged basins. The evaluation indicates that FLASH’s unit peak discharges had a linear and rank correlation of 0.64 and 0.79, respectively, and that the timing of the peak discharges has errors less than 2 h. The critical success index with FLASH was 0.38 for flood events that exceeded action stage. FLASH performance is demonstrated and evaluated for case studies, including the 2013 deadly flash flood case in Oklahoma City, Oklahoma, and the 2015 event in Houston, Texas—both of which occurred on Memorial Day weekends.

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Steven V. Vasiloff
,
Dong-Jun Seo
,
Kenneth W. Howard
,
Jian Zhang
,
David H. Kitzmiller
,
Mary G. Mullusky
,
Witold F. Krajewski
,
Edward A. Brandes
,
Robert M. Rabin
,
Daniel S. Berkowitz
,
Harold E. Brooks
,
John A. McGinley
,
Robert J. Kuligowski
, and
Barbara G. Brown

Accurate quantitative precipitation estimates (QPE) and very short term quantitative precipitation forecasts (VSTQPF) are critical to accurate monitoring and prediction of water-related hazards and water resources. While tremendous progress has been made in the last quarter-century in many areas of QPE and VSTQPF, significant gaps continue to exist in both knowledge and capabilities that are necessary to produce accurate high-resolution precipitation estimates at the national scale for a wide spectrum of users. Toward this goal, a national next-generation QPE and VSTQPF (Q2) workshop was held in Norman, Oklahoma, on 28–30 June 2005. Scientists, operational forecasters, water managers, and stakeholders from public and private sectors, including academia, presented and discussed a broad range of precipitation and forecasting topics and issues, and developed a list of science focus areas. To meet the nation's needs for the precipitation information effectively, the authors herein propose a community-wide integrated approach for precipitation information that fully capitalizes on recent advances in science and technology, and leverages the wide range of expertise and experience that exists in the research and operational communities. The concepts and recommendations from the workshop form the Q2 science plan and a suggested path to operations. Implementation of these concepts is expected to improve river forecasts and flood and flash flood watches and warnings, and to enhance various hydrologic and hydrometeorological services for a wide range of users and customers. In support of this initiative, the National Mosaic and Q2 (NMQ) system is being developed at the National Severe Storms Laboratory to serve as a community test bed for QPE and VSTQPF research and to facilitate the transition to operations of research applications. The NMQ system provides a real-time, around-the-clock data infusion and applications development and evaluation environment, and thus offers a community-wide platform for development and testing of advances in the focus areas.

Full access
Suzanne Van Cooten
,
Kevin E. Kelleher
,
Kenneth Howard
,
Jian Zhang
,
Jonathan J. Gourley
,
John S. Kain
,
Kodi Nemunaitis-Monroe
,
Zac Flamig
,
Heather Moser
,
Ami Arthur
,
Carrie Langston
,
Randall Kolar
,
Yang Hong
,
Kendra Dresback
,
Evan Tromble
,
Humberto Vergara
,
Richard A Luettich Jr.
,
Brian Blanton
,
Howard Lander
,
Ken Galluppi
,
Jessica Proud Losego
,
Cheryl Ann Blain
,
Jack Thigpen
,
Katie Mosher
,
Darin Figurskey
,
Michael Moneypenny
,
Jonathan Blaes
,
Jeff Orrock
,
Rich Bandy
,
Carin Goodall
,
John G. W. Kelley
,
Jason Greenlaw
,
Micah Wengren
,
Dave Eslinger
,
Jeff Payne
,
Geno Olmi
,
John Feldt
,
John Schmidt
,
Todd Hamill
,
Robert Bacon
,
Robert Stickney
, and
Lundie Spence

The objective of the Coastal and Inland Flooding Observation and Warning (CI-FLOW) project is to prototype new hydrometeorologic techniques to address a critical NOAA service gap: routine total water level predictions for tidally influenced watersheds. Since February 2000, the project has focused on developing a coupled modeling system to accurately account for water at all locations in a coastal watershed by exchanging data between atmospheric, hydrologic, and hydrodynamic models. These simulations account for the quantity of water associated with waves, tides, storm surge, rivers, and rainfall, including interactions at the tidal/surge interface.

Within this project, CI-FLOW addresses the following goals: i) apply advanced weather and oceanographic monitoring and prediction techniques to the coastal environment; ii) prototype an automated hydrometeorologic data collection and prediction system; iii) facilitate interdisciplinary and multiorganizational collaborations; and iv) enhance techniques and technologies that improve actionable hydrologic/hydrodynamic information to reduce the impacts of coastal flooding. Results are presented for Hurricane Isabel (2003), Hurricane Earl (2010), and Tropical Storm Nicole (2010) for the Tar–Pamlico and Neuse River basins of North Carolina. This area was chosen, in part, because of the tremendous damage inflicted by Hurricanes Dennis and Floyd (1999). The vision is to transition CI-FLOW research findings and technologies to other U.S. coastal watersheds.

Full access
J. K. Andersen
,
Liss M. Andreassen
,
Emily H. Baker
,
Thomas J. Ballinger
,
Logan T. Berner
,
Germar H. Bernhard
,
Uma S. Bhatt
,
Jarle W. Bjerke
,
Jason E. Box
,
L. Britt
,
R. Brown
,
David Burgess
,
John Cappelen
,
Hanne H. Christiansen
,
B. Decharme
,
C. Derksen
,
D. S. Drozdov
,
Howard E. Epstein
,
L. M. Farquharson
,
Sinead L. Farrell
,
Robert S. Fausto
,
Xavier Fettweis
,
Vitali E. Fioletov
,
Bruce C. Forbes
,
Gerald V. Frost
,
Sebastian Gerland
,
Scott J. Goetz
,
Jens-Uwe Grooß
,
Edward Hanna
,
Inger Hanssen-Bauer
,
Stefan Hendricks
,
Iolanda Ialongo
,
K. Isaksen
,
Bjørn Johnsen
,
L. Kaleschke
,
A. L. Kholodov
,
Seong-Joong Kim
,
Jack Kohler
,
Zachary Labe
,
Carol Ladd
,
Kaisa Lakkala
,
Mark J. Lara
,
Bryant Loomis
,
Bartłomiej Luks
,
K. Luojus
,
Matthew J. Macander
,
G. V. Malkova
,
Kenneth D. Mankoff
,
Gloria L. Manney
,
J. M. Marsh
,
Walt Meier
,
Twila A. Moon
,
Thomas Mote
,
L. Mudryk
,
F. J. Mueter
,
Rolf Müller
,
K. E. Nyland
,
Shad O’Neel
,
James E. Overland
,
Don Perovich
,
Gareth K. Phoenix
,
Martha K. Raynolds
,
C. H. Reijmer
,
Robert Ricker
,
Vladimir E. Romanovsky
,
E. A. G. Schuur
,
Martin Sharp
,
Nikolai I. Shiklomanov
,
C. J. P. P. Smeets
,
Sharon L. Smith
,
Dimitri A. Streletskiy
,
Marco Tedesco
,
Richard L. Thoman
,
J. T. Thorson
,
X. Tian-Kunze
,
Mary-Louise Timmermans
,
Hans Tømmervik
,
Mark Tschudi
,
Dirk van As
,
R. S. W. van de Wal
,
Donald A. Walker
,
John E. Walsh
,
Muyin Wang
,
Melinda Webster
,
Øyvind Winton
,
Gabriel J. Wolken
,
K. Wood
,
Bert Wouters
, and
S. Zador
Free access
Matthew L. Druckenmiller
,
Twila A. Moon
,
Richard L. Thoman
,
Thomas J. Ballinger
,
Logan T. Berner
,
Germar H. Bernhard
,
Uma S. Bhatt
,
Jarle W. Bjerke
,
Jason E. Box
,
R. Brown
,
John Cappelen
,
Hanne H. Christiansen
,
B. Decharme
,
C. Derksen
,
Dmitry Divine
,
D. S. Drozdov
,
A. Elias Chereque
,
Howard E. Epstein
,
L. M. Farquharson
,
Sinead L. Farrell
,
Robert S. Fausto
,
Xavier Fettweis
,
Vitali E. Fioletov
,
Bruce C. Forbes
,
Gerald V. Frost
,
Emily Gargulinski
,
Sebastian Gerland
,
Scott J. Goetz
,
Z. Grabinski
,
Jens-Uwe Grooß
,
Christian Haas
,
Edward Hanna
,
Inger Hanssen-Bauer
,
Stefan Hendricks
,
Robert M. Holmes
,
Iolanda Ialongo
,
K. Isaksen
,
Piyush Jain
,
Bjørn Johnsen
,
L. Kaleschke
,
A. L. Kholodov
,
Seong-Joong Kim
,
Niels J. Korsgaard
,
Zachary Labe
,
Kaisa Lakkala
,
Mark J. Lara
,
Bryant Loomis
,
K. Luojus
,
Matthew J. Macander
,
G. V. Malkova
,
Kenneth D. Mankoff
,
Gloria L. Manney
,
James W. McClelland
,
Walter N. Meier
,
Thomas Mote
,
L. Mudryk
,
Rolf Müller
,
K. E. Nyland
,
James E. Overland
,
T. Park
,
Olga Pavlova
,
Don Perovich
,
Alek Petty
,
Gareth K. Phoenix
,
Martha K. Raynolds
,
C. H. Reijmer
,
Jacqueline Richter-Menge
,
Robert Ricker
,
Vladimir E. Romanovsky
,
Lindsay Scott
,
Hazel Shapiro
,
Alexander I. Shiklomanov
,
Nikolai I. Shiklomanov
,
C. J. P. P. Smeets
,
Sharon L. Smith
,
Amber Soja
,
Robert G. M. Spencer
,
Sandy Starkweather
,
Dimitri A. Streletskiy
,
Anya Suslova
,
Tove Svendby
,
Suzanne E. Tank
,
Marco Tedesco
,
X. Tian-Kunze
,
Mary-Louise Timmermans
,
Hans Tømmervik
,
Mikhail Tretiakov
,
Mark Tschudi
,
Sofia Vakhutinsky
,
Dirk van As
,
R. S. W. van de Wal
,
Sander Veraverbeke
,
Donald A. Walker
,
John E. Walsh
,
Muyin Wang
,
Melinda Webster
,
Øyvind Winton
,
K. Wood
,
Alison York
, and
Robert Ziel
Free access