WARNING APPLICATIONS RESEARCH

Cintineo, J. L., T. M. Smith, V. Lakshmanan, K. L. Ortega, 2009: A real-time automated method to determine forecast confidence associated with tornado warnings. Extended Abstracts, 25th Conference on Interactive Information Processing Systems for Meteorology, Oceanography, and Hydrology, Phoenix, AZ, USA, American Meteorological Society, 4B.1.

This presentation describes the use of severe weather products derived from the coterminous United States (CONUS) radar network and model analysis fields to determine the confidence-level of National Weather Service-issued tornado warnings. Severe weather attributes such as low-level shear, reflectivity at -20C and the size of the convective core were extracted (within the geographic and temporal extent of the warning polygons) from the real-time grids produced by the Warning Decision Support System -- Integrated Information (WDSS-II). The initial values of these severe weather parameters at the time the warning was issued were used to determine the conditional probability that a tornado would occur within the spatial and temporal bounds of the warning. The results are based on NWS tornado warnings from May and July of 2008, and also based on verification data from the Storm Prediction Center's storm data, which were preliminary at the time the analysis was performed. Conditional probabilities are shown from two products: 0-2km azimuthal shear, and vertically integrated liquid. Once a warning is issued, it is possible to use this conditional probability to objectively assign a confidence value with the warning in real-time.

Available online at ://http://ams.confex.com/ams/89annual/techprogram/paper_150730.htm.

Kuhlman, K. M., D. R. MacGorman, M. I. Biggerstaff, P. R. Krehbiel, 2009: Lightning initiation in the anvils of two supercell storms. Geophysical Research Letters, 36, L07802.

Previous studies of lightning in anvil clouds have reported that flashes began in or near the storm core and propagated downwind into the anvil. It had been thought that flashes could not be initiated far downwind in the anvil, because anvil charge was thought to be produced mainly in the storm’s deep updraft and to decrease with distance into the anvil. Here we report observations of the in-cloud development of lightning flashes in the anvils of two supercell storms, including the first observations of flashes that began in the anvil 30–100 km from the cores of the storms and propagated upwind back toward the cores. Interaction between charge regions in the two converging anvils of adjoining storms appeared to cause some of the distant flash initiations, but a local charging mechanism in the anvil likely also contributed to the flash initiations. All flashes that struck ground beneath the distant anvil transferred negative charge to ground instead of the positive charge usually transferred to ground there, an apparent consequence of the parent storm having an inverted-polarity electrical structure.

Kuhlman, K. M., E. Gruntfest, K. A. Scharfenberg, G. J. Stumpf, 2009: Beyond Storm-Based Warnings: An Advanced WAS*IS Workshop to study communication of probabilistic hazardous weather information.. Extended Abstracts, 4th Symp. on Policy and Socio—Economic Research, Phoenix, AZ, USA, Amer. Meteor. Soc., CD-ROM, 3.5.

In September 2008, the National Weather Center hosted an Advanced Weather and Society Integrated Studies (WAS*IS) workshop. This workshop was designed to bring together research meteorologists at the NOAA Hazardous Weather Testbed experimental warning program, and a group of stakeholders representing a diverse user community, to integrate societal impact research at the beginning stages of the development of new gridded probabilistic hazardous weather information. The objectives of the workshop were to: 1) introduce new technologies/directions to a diverse spectrum of potential future collaborators, 2) define and address the needs of a broad spectrum of end-users, 3) clarify and suggest new ways to communicate uncertainty and storm information via emerging technologies, 4) define new measures of success to properly assess service, including changing concepts of storm verification including close calls and false alarms, 5) provide suggestions for the evolution of the Experimental Warning Program, designing spring experiments with stakeholders goals, 6) develop ideas for new ways to change the culture within all levels of the National Weather Service to facilitate operational implementation of these concepts, and 7) create visibility and consider possible future funding opportunities for Hazardous Weather Testbed activities and stakeholder interactions. We will discuss some of the outcomes of this workshop, including the cross-over activities with the development of a Next-Generation Warning Tool for the NWS.

Available online at ://http://ams.confex.com/ams/pdfpapers/150887.pdf.

Witt, A., R. A. Brown, Z. Jing, 2009: Performance of a new velocity dealiasing algorithm for the WSR-88D. Preprints, 34th Conference on Radar Meteorology, Williamsburg, VA, USA, AMS, P4.8.

Kuhlman, K. M., D. R. MacGorman, M. I. Biggerstaff, 2008: Spatial distribution of lightning data relative to kinematics in a HP tornadic supercell storm during TELEX. Preprints, 3rd Annual Conference on Applications of Lightning Data, New Orleans, LA, USA, American Meteorological Society, P1.3.

The Thunderstorm Electrification and Lightning Experiment (TELEX) observed a high-precipitation tornadic supercell storm on 29 May 2004. The available observation systems included the Oklahoma Lightning Mapping Array (LMA), the KOUN S-Band polarimetric radar, and two mobile SMART-R C-Band radars. Thunderstorm charge is thought to be produced by microphysical interactions between graupel and cloud ice followed by differential sedimentation to produce regions of net charge. If so, the kinematics of the storm govern spatial relationships between regions of microphysical charging and the location and geometry of those charge regions.

On 29 May 2004, lightning flashes near the core of this storm, although quite frequent, tended to have shorter duration and smaller horizontal extent than typical flashes in other storms having less frequent lightning. We suggest that this is due, at least in part, to small pockets of opposite charge lying in close proximity to each other. Thus, each polarity of lightning leader propagates only a relatively short distance before reaching regions of unfavorable electrical potential. In the anvil, however, lightning extended tens of kilometers from the reflectivity cores in roughly horizontal layers, consistent with the charge spreading through the anvil in broad sheets. Though lightning has been previously observed in anvils, typically this lightning is initiated in or near the core of the storm and extends out into the anvil. Yet, in the 29 May 2004 storm, flashes initiated in the anvil region and the subsequent leaders progressed back towards the core of the storm. Some of these flashes were negative cloud-to-ground flashes that initiated over 50 km away from the core and struck ground beneath the anvil close to the initiation point. We hypothesize that interaction between the anvil of this supercell and a somewhat lower anvil of opposite polarity from a weaker left-moving cell to the north was responsible for initiating this lightning.

Available online at ://http://www.ametsoc.org.

Kuhlman, K. M., T. M. Smith, G. J. Stumpf, K. L. Ortega, K. L. Manross, 2008: Experimental probabilistic hazard information in practice: Results from the 2008 EWP Spring Program. Extended Abstracts, 24th Conference on Severe Local Storms, Savannah, GA, USA, American Meteorological Society, 8A.1.

The National Oceanic and Atmospheric Administration's (NOAA) National Weather Service (NWS) has recently transitioned to "storm-based" warnings from county-based warnings. These warnings are increasingly used by graphical applications for television, the Internet, and cell phones to better communicate specific information about hazardous weather. With the rapid updates in technology and communication, the NWS can continue to build upon the storm-based warnings to better communicate specifics in uncertainty, space, and time to advanced and special-need users.

During the 6 week period of 27 April - 7 June 2008, the NOAA Hazardous Weather Testbed in Norman, OK hosted multiple visiting NWS and Environment Canada forecasters for the Experimental Warning Program (EWP). The forecasters had the opportunity to issue probabilistic guidance on several real-time severe weather events across the continental United States and an archive event from 13 August 2007 in northeast North Dakota. Each forecaster was asked to identify areas of a storm where a threat was possible, either at the current time or near future (less than 60 min) and determine a probability associated with that threat (current and at a chosen future time). The project focused on three different threats: Tornado, Hail (greater than .75 in), and Wind (greater than 50 kts). Probabilistic warning forecasts made throughout the six week period and from the archive event will be compared to the high resolution data from the Severe Hazards Analysis & Verification Experiment (SHAVE) to determine skill and reliability of the forecasts and how this guidance should be updated for future use.

Available online at ://http://ams.confex.com/ams/24SLS/techprogram/paper_142027.htm.

Kuhlman, K. M., E. R. Mansell, C. L. Ziegler, M. I. Biggerstaff, D. R. MacGorman, D. C. Dowell, 2008: EnKF data assimilation and dual-Doppler analysis of the 29 May 2004 Geary, Oklahoma supercell. Proc. 24th Conference on Severe Local Storms, Savannah, GA, USA, American Meteorological Society, P5.1.

On 29 May 2004, a long-track supercell storm moved across Oklahoma producing multiple tornadoes and numerous reports of large hail. Two mobile, C-band, Doppler (SMART-R) radars collected data in 2.5 min volume scans almost continuously for more than three hours. Dual-Doppler analyses were completed for select times using a1 km grid spacing and a 2-pass Barnes objective analysis in the interpolation of radial velocities and reflectivity to a Cartesian grid following Majcen et al (2008).

The focus of the radar data assimilation for this study is to retrieve the state of the storm rather than to develop forecast applications. For this purpose, the ensemble Kalman filter (EnKF) technique is used to assimilate reflectivity and/or radial velocity data into the model from SMART radar at approximately five minute intervals. Comparisons of the simulations employing EnKF to a simulation without data assimilation and to the dual-Doppler syntheses at various times of the storm's life-cycle will be presented. These results will be used to quantify the agreement between the simulation and the observations providing background such that future studies may use the simulations in order to to retrieve unobserved fields.

Available online at ://http://ams.confex.com/ams/24SLS/techprogram/paper_142031.htm.

Manross, K. L., T. M. Smith, J. T. Ferree, G. J. Stumpf, 2008: An on-demand user interface for requesting multi-radar, multi-sensor time accumulated products to support severe weather verification. Extended Abstracts, 23rd Conference on Interactive Information Processing Systems, New Orleans, LA, USA, AMS, P2.13.

NSSL has a long history of developing radar based applications and algorithms intended to aid forecasters in warning decision making. With the advent of the WDSSII system, new and more robust algorithms are being developed in short amounts of time. Thanks to the GIS-based Google Earth application, NSSL has been able to display real-time algorithm output via the World Wide Web for feedback on these algorithms. As a result, many of these algorithms have not only proven useful and accurate, but also popular, particularly in short-term post-event storm survey and verification situations. Time accumulated Maximum Expected Size of Hail ("MESH") and time accumulated radar detected maximum low-altitude rotational shear ("Rotation Tracks") are two products that seem to be particularly useful. The latter has been used to aid forecasters in tornado damage surveys performed by National Weather Service (NWS) personnel at numerous Weather Service Forecast Offices. Emergency managers may also find these plots useful for disaster response.

Currently these data are continuously being produced on the CONUS scale and are stored in a short term archive (up to one week). For specific events, or by request, the data can be manually reprocessed for smaller regions and short time scales and are occasionally archived indefinitely. A recently funded proposal has allowed for automated, on-demand requests of these products by end-users. Forecasters may specify region-specific GIS-encoded data for requested time periods using a web-based graphical user interface. This paper details this process as well as explaining the user interface.

Available online at ://http://ams.confex.com/ams/88Annual/techprogram/paper_134621.htm.

Ortega, K. L., A. G. Kolodziej, J. Young, C. J. Wilson, A. Witt, T. M. Smith, 2008: Evaluating hail diagnosis techniques using high resolution verification. Extended Abstracts, 24th Conference on Severe Local Storms, Savannah, GA, USA, American Meteorological Society, CD-ROM, P6.5.

During the summers of 2006, 2007 and 2008, the National Severe Storms Laboratory conducted high resolution verification efforts on numerous severe weather events across the U.S. This project was originally called the Severe Hail Verification Experiment (SHAVE), with the name later changed to the Severe Hazards Analysis and Verification Experiment (SHAVE) to reflect differences in how the experiment was conducted. During all three years, the primary goal of SHAVE was to collect hail reports at higher resolution than what is available through Storm Data. This study will evaluate the performance of several hail diagnosis techniques. These techniques include a hail diagnosis algorithm which utilizes several radar reflectivity and velocity based parameters together with environmental data in the vicinity of a storm, and multi-radar, multi-sensor hail diagnosis grids. Results using SHAVE reports will be compared to results using Storm Data to assess whether differences in algorithm skill result from differences in verification data resolution. Also, variations in near-storm environment and storm structure will be compared for several cases.

Available online at ://http://ams.confex.com/ams/24SLS/techprogram/paper_142039.htm.

Ortega, K. L., 2008: Severe weather warnings and warning verification using threat areas. M.S. thesis, School of Meteorology, University of Oklahoma, 50 pp.

On October 1, 2007, the National Weather Service (NWS) changed its warning system from a county-based system to a storm-based system. In the storm-based warning system, the forecaster draws a warning polygon that is supposed to highlight the area under threat from the storm without regard for geopolitical boundaries (such as county boundaries). A leading reason for the change was to reduce the false alarm area caused by warning-by-county. While the goal seems worthwhile, the NWS currently has no tools or capabilities to measure the false alarm area reduction. All warning skill measures, such as probability of detection, are calculated from reports of severe weather; questions arise since the reports are discrete points that are widely separated in space and time. Previous studies (Witt et al. 1998 and Trapp et al. 2006) highlighted not only representativeness concerns, but also problems in accuracy of some reports' time, location and magnitude.
This study will explore the utility of new warning techniques based on threat areas and storm motion. A threat area is defined as an area expected to receive, currently is receiving or has received a severe weather threat. This study will limit its severe weather threat to hail. While NWS techniques allow the forecaster to draw the polygon, the techniques explored in this study will be locked to a storm motion and motion uncertainty to highlight the warned area. Two warning guidance methods will be explored: the first allows the forecaster to highlight the current threat area and that area is translated along the storm motion and motion uncertainty. The second method uses an algorithm to highlight the current threat area by evaluating output from a gridded version of the Hail Detection Algorithm (HDA; Witt et al. 1998). This second method will also ix
explore the capability of classifying the magnitude of the threat and increasing or decaying the classification with time.
This study will also explore the scoring of warnings based on areas and population using two unique datasets. The first dataset is an archive of high-resolution hail verification from the Severe Hail Verification Experiment (SHAVE; Smith et al. 2006) that was conducted at the National Severe Storms Laboratory during the summer of 2006. This verification dataset allowed for the creation and scoring of verification grids created from reflectivity and gridded HDA output. The second dataset is a high-resolution population grid available from Oak Ridge National Laboratory. Scoring the warnings using the population grid can easily answer questions such as "did the warning cover the population under threat?"

Smith, T. M., V. Lakshmanan, 2008: Real-time and recent historical weather data in Google Earth. Extended Abstracts, 23rd Conference on Interactive Information Processing Systems, New Orleans, LA, USA, AMS, 9B.6.

The National Severe Storms Laboratory (NSSL) utilizes Google Earth as one of several ways to share experimental severe weather products with other researchers and operational meteorologists for evaluation and feedback. A variety of multi-sensor severe weather products are generated by NSSL and shared to Google Earth users via the internet at http://wdssii.nssl.noaa.gov. These products include spatially gridded fields of Vertically Integrated Liquid, Maximum Expected Hail Size, tracks of circulations derived from Doppler velocity data, composite reflectivity, and 30-to-60 minute forecast reflectivity fields, among others. These products, which have a spatial resolution of approximately 1 km by 1 km, are generated every one to five minutes within the Warning Decision Support System – Integrated Information (WDSS-II). The WDSS-II system provides the images in GeoTIFF format which may be imported into most Geographic Information Systems software including virtual globes such as Google Earth.

During the first two years these data have been provided on the internet, they have been used to improve the verification of severe weather events as well as in disaster response and post-event damage assessments. This presentation focuses on the scientific and educational uses of virtual globes to interrogate real-time and archived severe weather products.

Available online at ://http://http://ams.confex.com/ams/88Annual/techprogram/paper_134923.htm.

Kuhlman, K., D. MacGorman, D. Rust, P. Krehbiel, B. Rison, 2007: Lightning in the anvil region of a supercell storm. Preprints, 13th International Conference on Atmospheric Electricity, Beijing, China, IUGG/Commission on Atmospheric Electricity, PS5-8.

The Thunderstorm Electrification and Lightning Experiment (TELEX) took place in central Oklahoma during the 2003 and 2004 convective seasons to study the lightning, dynamics and microphysics of thunderstorms. One storm from this field project, a high-precipitation tornadic supercell occurred on 29 May 2004. In this storm, the Oklahoma Lightning Mapping Array detected lightning extending over one hundred kilometers away from the core of the supercell. Lightning is known to occur in the anvil region of supercells; typically this lightning is initiated in the core of the storm and extends out through the anvil. In the 29 May 2004 storm, however, some flashes actually initiated in the anvil region and the subsequent leaders progressed back towards the core of the storm. Some of these flashes were negative cloud-to-ground flashes that initiated over 50 km away from the core and struck ground beneath the anvil close to the initiation point. It appears that interaction between the anvil of this supercell and an anvil of opposite polarity from a weaker left-moving cell to the north was responsible for initiating this lightning.

Smith, T. M., P. L. Heinselman, D. Priegnitz, 2007: Characteristics of microburst events observed with the National Weather Radar Testbed phased array radar. Preprints, 23rd Conference on Interactive Information Processing Systems, San Antonio, TX, USA, AMS, CD-ROM, 7.8.

Microbursts are small-scale (< 4 km diameter) outflows induced by strong downdrafts in thunderstorms that frequently cause damage to property and are a hazard to aviators. Many severe microbursts originate from storm cells that form in regions of moderate-to-high Convective Available Potential Energy (CAPE), weak environmental shear, and environments that are highly unstable to downdraft formation. These storm cells typically have a life cycle of 20-40 minutes, which makes them very difficult to predict.

Automated algorithms that analyze radar data and make short-term predictions for microburst events, as well as detecting low-altitude divergence signatures associated with their outflows, have been implemented for WSR-88D and TDWR systems. These applications rely on microburst “precursors” that may be observed at the higher altitudes of a storm shortly preceding the outflow at the surface to make short-lead-time forecasts of a microburst event. However, microburst events evolve rapidly, and because these radars typically only sample the upper portions of a storm once every 4 to 6 minutes (depending on scanning strategy), they may not sample key precursor features aloft or the near-surface outflow.

This presentation examines damage-producing severe microburst events that occurred in Central Oklahoma during July 2006 that were observed with the National Weather Radar Testbed (NWRT) Phased Array Radar (PAR). These storms formed within 50 km of the PAR site and were sampled with a temporal resolution of 15 to 30 seconds. We will compare the PAR observations of the storms with the KTLX WSR-88D, OKC TDWR, and multi-radar, multi-sensor information from the Warning Decision Support System – Integrated Information.

Available online at ://http://ams.confex.com/ams/pdfpapers/120074.pdf.

Smith, T. M., K. L. Ortega, A. G. Kolodziej, 2007: Enhanced, high-density severe storm verification. Preprints, 23rd Conference on Interactive Information Processing Systems, San Antonio, TX, USA, AMS, CD-ROM, 4B.3.

The Severe Hail Verification Experiment (SHAVE) was conducted during May through August of 2006. Researchers in SHAVE combined radar and environmental information available from the National Severe Storms Laboratory's Warning Decision Support System – Integrated Information (WDSS-II) with geographic information available in Google Earth and other sources. This information was used to identify locations to make targeted telephone calls to the public in regions where storms occurred within minutes of an event in order to collect information about the occurrence, size, and duration of hail. During the experiment, hail swaths from severe thunderstorms were documented at a much higher spatial and temporal resolution than is available in the National Climate Data Center's Storm Data publication and in National Weather Service (NWS) local storm report products.

The presentation shows results from SHAVE and compares the independently collected, high-resolution data with traditional NWS verification data for hail, and discusses the uncertainties associated with both data sets. We discuss the benefits of the improved verification data and their implications for warning verification and future changes in the NWS warning paradigm, such as “warning polygons” and probabilistic threat area warnings. We also consider improvements to the data collection methodologies and the expansion of the experiment in 2007 to include the analysis of severe wind events and other threats.

Available online at ://http://ams.confex.com/ams/pdfpapers/120091.pdf.

Witt, A., 2007: Performance of two velocity dealiasing algorithms on Terminal Doppler Weather Radar data. Preprints, 33rd Conference on Radar Meteorology, Cairns, Australia, American Meteorological Society, CD-ROM, P13A.14.

Kuhlman, K. M., C. L. Ziegler, E. R. Mansell, D. R. MacGorman, J. M. Straka, 2006: Numerically Simulated Electrification and Lightning of the 29 June 2000 STEPS Supercell Storm. Monthly Weather Review, 134, 2734-2757.

A three-dimensional dynamic cloud model incorporating airflow dynamics, microphysics, and thunderstorm electrification mechanisms is used to simulate the first 3 h of the 29 June 2000 supercell from the Severe Thunderstorm Electrification and Precipitation Study (STEPS). The 29 June storm produced large flash rates, predominately positive cloud-to-ground lightning, large hail, and an F1 tornado. Four different simulations of the storm are made, each one using a different noninductive (NI) charging parameterization. The charge structure, and thus lightning polarity, of the simulated storm is sensitive to the treatment of cloud water dependence in the different NI charging schemes. The results from the simulations are compared with observations from STEPS, including balloon-borne electric field meter soundings and flash locations from the Lightning Mapping Array. For two of the parameterizations, the observed “inverted” tripolar charge structure is well approximated by the model. The polarity of the ground flashes is opposite that of the lowest charge region of the inverted tripole in both the observed storm and the simulations. Total flash rate is well correlated with graupel volume, updraft volume, and updraft mass flux. However, there is little correlation between total flash rate and maximum updraft speed. Based on the correlations found in both the observed and simulated storm, the total flash rate appears to be most representative of overall storm intensity.

Available online at ://http://www.ametsoc.org.

Kuhlman, K., D. MacGorman, M. Biggerstaff, W. D. Rust, T. Schuur, C. Ziegler, P. Krehbiel, 2006: Lightning and radar observatons of the 29 May 2004 supercell during TELEX. Preprints, 2nd Conference on Meteorological Applications of Lightning Data, Atlanta, GA, USA, American Meteorological Society, 3.3.

Manross, K. L., J. G. LaDue, 2006: New Features of the VCPExplorer: Simulated Precipitation. Extended Abstracts, 22nd International Conference on Interactive Information Processing Systems for Meteorology, Oceanography, and Hydrology, Atlanta, GA, USA, American Meteorological Society, CD-ROM, 2.11. [Available from Kevin L. Manross, National Severe Storms Laboratory, 120 David L. Boren Blvd., Norman, OK, USA, 73072.]

The VCPExplorer is an instructional tool that aides in the visualization of radar scanning strategies, including radar beam propagation path relative to terrain, and radar algorithm dependence on volume coverage pattern (VCP). The VCPExplorer has been used in the Warning Decision Training Branch's (WDTB) Advanced Warning Operations Course (AWOC) and has been upgraded with several new features to simulate radar sampling issues of precipitation. Among the new features are radar estimated rainfall. The user can modify several parameters including ZR relationship, VCP, and reflectivity profile and compare the radar estimated (based on VCP and terrain-based hybrid scan) rainfall to the "true" (based on radar reflectivity at the Earth's surface) rainfall. Other new features include simulated "bright-banding" and sub-cloud evaporation effects on radar reflectivity.

Available online at ://http://ams.confex.com/ams/Annual2006/techprogram/paper_104425.htm.

Ortega, K. L., T. M. Smith, G. J. Stumpf, 2006: Verification of multi-sensor, multi-radar hail diagnosis techniques. Preprints, Symposium on the Challenges of Severe Convective Storms, Atlanta, GA, USA, American Meteorological Society, CD-ROM, P1.1.

Ortega, K. L., T. M. Smith, K. A. Scharfenberg, 2006: An analysis of thunderstorm hail fall patterns in the Severe Hail Verification Experiment. Preprints, 23rd Conference on Severe Local Storms, St. Louis, MO, USA, AMS, CD-ROM, P2.4.

Available online at ://http://ams.confex.com/ams/23SLS/techprogram/paper_115441.htm.

Smith, T. M., V. Lakshmanan, 2006: Utilizing Google Earth as a GIS platform for weather applications. Preprints, 22nd Conference on Interactive Information Processing Systems, Atlanta, GA, USA, AMS, CD-ROM, 8.2.

Available online at ://http://ams.confex.com/ams/Annual2006/techprogram/paper_104847.htm.

Smith, T. M., K. L. Ortega, K. A. Scharfenberg, K. M. Manross, A. Witt, 2006: The Severe Hail Verfication Experiment. Preprints, 23rd Conference on Severe Local Storms, St. Louis, MO, USA, AMS, CD-ROM, 5.3.

Available online at ://http://ams.confex.com/ams/23SLS/techprogram/paper_115436.htm.

Manross, K. L., J. G. LaDue, G. Stumpf, 2005: The Volume Coverage Pattern Explorer: A new tool for visualizing radar beam paths. Preprints, 21st International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology, San Diego, CA, USA, American Meteorological Society, CD-ROM, 5.5.

Ortega, K. L., T. M. Smith, G. J. Stumpf, J. Hocker, L. López, 2005: A comparison of multi-sensor hail diagnosis techniques. Preprints, 21st International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology, San Diego, CA, USA, American Meteorological Society, P1.11.

Smith, T. M., G. J. Stumpf, 2005: Multi-sensor storm cell identification and analysis. Preprints, 21st International Conference on Interactive Information and Processing Systems (IIPS) for Meteorology, Oceanography, and Hydrology, San Diego, CA, USA, American Meteorological Society, P1.10.

Witt, A., R. A. Brown, V. Lakshmanan, 2005: Real-time calculation of horizontal winds using multiple Doppler radars: A new WDSS-II module. Preprints, 32nd Conference on Radar Meteorology, Albuquerque, NM, USA, Amer. Meteor. Soc., CD-ROM, P8R.7.

Manross, K. L., R. J. Trapp, G. J. Stumpf, 2004: WSR-88D radar characteristics of quasi-linear convective system tornadoes using the NSSL Severe Storm Analysis Program. Preprints, 22nd Conference on Severe Local Storms, Hyannis, MA, USA, American Meteorological Society, CD-ROM, 8B.2.

Smith, T. M., K. L. Elmore, S. A. Dulin, 2004: A damaging downburst prediction and detection algorithm for the WSR-88D. Weather and Forecasting, 19, 240-250.

Kuhlman, K. M., E. R. Mansell, C. L. Ziegler, D. R. MacGorman, J. Straka, 2003: Charging and lightning simulations of the 29 June 2000 STEPS Supercell. Proc. 12th International Conference on Atmospheric Electricity, Versailles, France, 199-202.

Manross, K. L., R. J.Trapp, G. J.Stumpf, 2003: WSR-88D radar characteristics of quasi-linear convective system tornadoes using the NSSL severe storm analysis program. Preprints, 31st International Conference on Radar Meteorology, Seattle, WA, USA, American Meteorological Society, P2C.4.

Smith, T. M., K. L. Elmore, G. J. Stumpf, V. Lakshmanan, 2003: Detection of rotation and boundaries using two-dimensional, local, linear least squares estimates of velocity derivatives. Preprints, 31st International Conference on Radar Meteorology, Seattle, WA, USA, American Meteorological Society, 310-313.

Smith, T. M., K. L. Elmore, G. J. Stumpf, V. Lakshmanan, 2003: The operational use of rotation and divergence fields derived from Doppler radial velocities. 18th Annual Meeting of the National Weather Association, Jacksonville, FL, USA, National Weather Association, XX-XX.

Smith, T. M., G. J. Stumpf, K. L. Manross, C. Thomas, 2003: Warning Decision Support System - Integrated Information (WDSS-II). Part I: Multiple-sensor severe weather applications development at NSSL during 2002. Preprints, 19th International Conference on Interactive Information Processing Systems for Meteorology, Oceanography, and Hydrology (IIPS), LongBeach, CA, USA, American Meteorological Society, CD-ROM, 14.8.