Civil Engineers use probabilistic estimates of rainfall intensities for particular durations and ... more Civil Engineers use probabilistic estimates of rainfall intensities for particular durations and locations for the design of a wide range of structures from urban storm water drainage systems to dams and spillways. More
The rainfall frequency atlases and technical papers published by the National Oceanic and Atmosph... more The rainfall frequency atlases and technical papers published by the National Oceanic and Atmospheric Administration’s (NOAA) National Weather Service (NWS) serve as national standards for rainfall intensity at specified frequencies and durations in the United States.
The rainfall frequency atlases and technical papers published by the National Oceanic and Atmosph... more The rainfall frequency atlases and technical papers published by the National Oceanic and Atmospheric Administration's (NOAA) National Weather Service
Accurate estimation of the spatial and temporal distribution of rainfall is a crucial input param... more Accurate estimation of the spatial and temporal distribution of rainfall is a crucial input parameter for hydrologic model calibration and validation. The number of rain gauges used to monitor rainfall is generally inadequate to resolve the spatial and temporal distributions of rainfall over a watershed. Typically, spatial rainfall distributions have been estimated by developing a spatial pattern based on rain gauge observations using Thiessen polygons, inverse distance weighting or geostatistical techniques. The spatial distributions inferred from these techniques do not accurately represent the actual precipitation pattern. Techniques have been developed to calibrate NEXRAD radar data with rain gauge data to improve the accuracy of radar rainfall estimates, and produce high spatial and temporal resolution rainfall information for use in hydrologic model calibration and validation. The Storm Precipitation Analysis System (SPAS) precipitation-radar algorithms were used along with Na...
Describing floods in terms of an average recurrence internal (ARI) or “return period” (100-year) ... more Describing floods in terms of an average recurrence internal (ARI) or “return period” (100-year) has been used for decades to convey the rareness of major flooding events. However, describing the intensity of heavy rainstorms in a similar manner has not been as routine, but provides an equally good perspective of extreme rainfall events. Although the ARI of rainfall does not necessarily equate to a flood of the same ARI, ARI maps of rainfall provide an excellent indicator of flooding potential. Plus, real-time ARI maps of rainfall provide forecasters and media outlets a critical alternative to stream gauge information during rain-induced flooding events, especially considering flooding can often destroy or cause stream gauges to malfunction. The concept of ARI rainfall mapping has been used in recent government documents pertaining to extreme rainstorms. However, this paper/presentation will introduce the concept of real-time ARI rainfall maps, a new tool for conveying the magnitude...
World Environmental and Water Resource Congress 2006, 2006
The paper discusses an L-moments based regional rainfall frequency approach and its application i... more The paper discusses an L-moments based regional rainfall frequency approach and its application in large areas with many regions and across a broad range of durations. Advantages of the technique in terms of robustness to outliers and stability of quantile estimates are demonstrated through real examples. This paper provides an overview of NOAA Atlas 14, the updates of the rainfall frequency atlases and technical papers published by the National Oceanic and Atmospheric Administration’s National Weather Service for the Semiarid Southwest United States and the Ohio River Basin and surrounding states, focusing on technical/statistical aspects and developments and findings during the studies, such as 1) the criteria for identifying and verifying homogenous regions in a large area, 2) the goodness-of-fit for comparison and identification of distributions to best model the data in a region, 3) the concept of the real-data check and its use in regional frequency analysis, 4) consistency adjustments over a broad range of durations from 1-hour to 60-days, 5) identification of intersite dependence of the annual extreme precipitation and its impact on quantile estimates, 6) confidence limits as an uncertainty measure of the quantile estimates and, 7) the ratios of Partial Duration Series quantiles to Annual Maxima Series quantiles.
ABSTRACT A number of peer-reviewed, spatial climate datasets of excellent quality and detail for ... more ABSTRACT A number of peer-reviewed, spatial climate datasets of excellent quality and detail for the United States are now available. The datasets are suitable for a variety of modeling, analysis, and decision-making activities. These products are the result of collaboration between Oregon State University, USDA-NRCS, and other agencies. The development of high-quality maps was made possible through the use of PRISM, a climate analysis system that uses point climate data, a digital elevation model, and other spatial datasets to generate gridded, GIS-compatible estimates of annual, monthly and event-based climatic elements. Mapped elements currently available include 1961-90 mean monthly and annual precipitation, maximum temperature, minimum temperature, snowfall, heating and cooling degree days, growing degree days, median last spring and first fall frost dates, and mean growing season length. In addition, century-long time series of monthly precipitation and minimum and maximum temperature will soon be available for the lower 48 states.
High-quality, high-spatial-resolution temperature and precipitation data sets for the continental... more High-quality, high-spatial-resolution temperature and precipitation data sets for the continental United States are now available (ie, NRCS PRISM project). However, these data sets provide only climatological means, which do not adequately reflect the rich history of climate variability and trends contributing to these means. There is a great need for high-resolution, sequential monthly data sets of temperature and precipitation over an extended period for the continental US Such data sets would enable, for example:
Currently, the only high-quality, high-resolution temperature and precipitation data sets for the... more Currently, the only high-quality, high-resolution temperature and precipitation data sets for the continental United States suitable for use on climatological time scales are for mean values. None yet exist that represent sequential monthly values over an extended historical ...
On the week of Sept 9-16, 2013 very moist air originating in the tropics both E and SW of Mexico ... more On the week of Sept 9-16, 2013 very moist air originating in the tropics both E and SW of Mexico moved northward into Colorado. Very heavy rains developed in several areas. The heaviest rains fell over about a 36 hour period from the afternoon of the 11th to early morning on the 13th but with additional rains falling until early on the 17th. Rainfall patterns, timing, duration and intensity for this remarkable storm will be shown. The heaviest rains in Boulder Creek and the Poudre River watersheds fell in the lower foothills while in the St. Vrain and Big Thompson basins heavier rains covered larger high-elevation areas. In addition, areas near Colorado Springs received intense rains including 11.85" at a weather station on Fort Carson. This will establish a new one-day rainfall record for the state of Colorado.
Accurate estimation of the spatial and temporal distribution of rainfall is a crucial input param... more Accurate estimation of the spatial and temporal distribution of rainfall is a crucial input parameter into a surface water model for hydrologic model calibration and validation. Typically, the number of rain gauges used to monitor rainfall is generally inadequate to resolve the spatial and temporal distributions of rainfall over the watershed. Techniques have been developed to calibrate NEXRAD radar data
Applied Weather Associates (AWA) has completed a regional probable maximum precipitation (PMP) st... more Applied Weather Associates (AWA) has completed a regional probable maximum precipitation (PMP) study for the state of Nebraska. This project provides a PMP analysis that includes comprehensive evaluations of extreme rainfall storm events including storm analyses, storm maximization, storm transpositioning, and storm aspect ratio and orientation evaluations. The results of these analyses provide the basis for computing PMP values across
Civil Engineers use probabilistic estimates of rainfall intensities for particular durations and ... more Civil Engineers use probabilistic estimates of rainfall intensities for particular durations and locations for the design of a wide range of structures from urban storm water drainage systems to dams and spillways. More
The rainfall frequency atlases and technical papers published by the National Oceanic and Atmosph... more The rainfall frequency atlases and technical papers published by the National Oceanic and Atmospheric Administration’s (NOAA) National Weather Service (NWS) serve as national standards for rainfall intensity at specified frequencies and durations in the United States.
The rainfall frequency atlases and technical papers published by the National Oceanic and Atmosph... more The rainfall frequency atlases and technical papers published by the National Oceanic and Atmospheric Administration's (NOAA) National Weather Service
Accurate estimation of the spatial and temporal distribution of rainfall is a crucial input param... more Accurate estimation of the spatial and temporal distribution of rainfall is a crucial input parameter for hydrologic model calibration and validation. The number of rain gauges used to monitor rainfall is generally inadequate to resolve the spatial and temporal distributions of rainfall over a watershed. Typically, spatial rainfall distributions have been estimated by developing a spatial pattern based on rain gauge observations using Thiessen polygons, inverse distance weighting or geostatistical techniques. The spatial distributions inferred from these techniques do not accurately represent the actual precipitation pattern. Techniques have been developed to calibrate NEXRAD radar data with rain gauge data to improve the accuracy of radar rainfall estimates, and produce high spatial and temporal resolution rainfall information for use in hydrologic model calibration and validation. The Storm Precipitation Analysis System (SPAS) precipitation-radar algorithms were used along with Na...
Describing floods in terms of an average recurrence internal (ARI) or “return period” (100-year) ... more Describing floods in terms of an average recurrence internal (ARI) or “return period” (100-year) has been used for decades to convey the rareness of major flooding events. However, describing the intensity of heavy rainstorms in a similar manner has not been as routine, but provides an equally good perspective of extreme rainfall events. Although the ARI of rainfall does not necessarily equate to a flood of the same ARI, ARI maps of rainfall provide an excellent indicator of flooding potential. Plus, real-time ARI maps of rainfall provide forecasters and media outlets a critical alternative to stream gauge information during rain-induced flooding events, especially considering flooding can often destroy or cause stream gauges to malfunction. The concept of ARI rainfall mapping has been used in recent government documents pertaining to extreme rainstorms. However, this paper/presentation will introduce the concept of real-time ARI rainfall maps, a new tool for conveying the magnitude...
World Environmental and Water Resource Congress 2006, 2006
The paper discusses an L-moments based regional rainfall frequency approach and its application i... more The paper discusses an L-moments based regional rainfall frequency approach and its application in large areas with many regions and across a broad range of durations. Advantages of the technique in terms of robustness to outliers and stability of quantile estimates are demonstrated through real examples. This paper provides an overview of NOAA Atlas 14, the updates of the rainfall frequency atlases and technical papers published by the National Oceanic and Atmospheric Administration’s National Weather Service for the Semiarid Southwest United States and the Ohio River Basin and surrounding states, focusing on technical/statistical aspects and developments and findings during the studies, such as 1) the criteria for identifying and verifying homogenous regions in a large area, 2) the goodness-of-fit for comparison and identification of distributions to best model the data in a region, 3) the concept of the real-data check and its use in regional frequency analysis, 4) consistency adjustments over a broad range of durations from 1-hour to 60-days, 5) identification of intersite dependence of the annual extreme precipitation and its impact on quantile estimates, 6) confidence limits as an uncertainty measure of the quantile estimates and, 7) the ratios of Partial Duration Series quantiles to Annual Maxima Series quantiles.
ABSTRACT A number of peer-reviewed, spatial climate datasets of excellent quality and detail for ... more ABSTRACT A number of peer-reviewed, spatial climate datasets of excellent quality and detail for the United States are now available. The datasets are suitable for a variety of modeling, analysis, and decision-making activities. These products are the result of collaboration between Oregon State University, USDA-NRCS, and other agencies. The development of high-quality maps was made possible through the use of PRISM, a climate analysis system that uses point climate data, a digital elevation model, and other spatial datasets to generate gridded, GIS-compatible estimates of annual, monthly and event-based climatic elements. Mapped elements currently available include 1961-90 mean monthly and annual precipitation, maximum temperature, minimum temperature, snowfall, heating and cooling degree days, growing degree days, median last spring and first fall frost dates, and mean growing season length. In addition, century-long time series of monthly precipitation and minimum and maximum temperature will soon be available for the lower 48 states.
High-quality, high-spatial-resolution temperature and precipitation data sets for the continental... more High-quality, high-spatial-resolution temperature and precipitation data sets for the continental United States are now available (ie, NRCS PRISM project). However, these data sets provide only climatological means, which do not adequately reflect the rich history of climate variability and trends contributing to these means. There is a great need for high-resolution, sequential monthly data sets of temperature and precipitation over an extended period for the continental US Such data sets would enable, for example:
Currently, the only high-quality, high-resolution temperature and precipitation data sets for the... more Currently, the only high-quality, high-resolution temperature and precipitation data sets for the continental United States suitable for use on climatological time scales are for mean values. None yet exist that represent sequential monthly values over an extended historical ...
On the week of Sept 9-16, 2013 very moist air originating in the tropics both E and SW of Mexico ... more On the week of Sept 9-16, 2013 very moist air originating in the tropics both E and SW of Mexico moved northward into Colorado. Very heavy rains developed in several areas. The heaviest rains fell over about a 36 hour period from the afternoon of the 11th to early morning on the 13th but with additional rains falling until early on the 17th. Rainfall patterns, timing, duration and intensity for this remarkable storm will be shown. The heaviest rains in Boulder Creek and the Poudre River watersheds fell in the lower foothills while in the St. Vrain and Big Thompson basins heavier rains covered larger high-elevation areas. In addition, areas near Colorado Springs received intense rains including 11.85" at a weather station on Fort Carson. This will establish a new one-day rainfall record for the state of Colorado.
Accurate estimation of the spatial and temporal distribution of rainfall is a crucial input param... more Accurate estimation of the spatial and temporal distribution of rainfall is a crucial input parameter into a surface water model for hydrologic model calibration and validation. Typically, the number of rain gauges used to monitor rainfall is generally inadequate to resolve the spatial and temporal distributions of rainfall over the watershed. Techniques have been developed to calibrate NEXRAD radar data
Applied Weather Associates (AWA) has completed a regional probable maximum precipitation (PMP) st... more Applied Weather Associates (AWA) has completed a regional probable maximum precipitation (PMP) study for the state of Nebraska. This project provides a PMP analysis that includes comprehensive evaluations of extreme rainfall storm events including storm analyses, storm maximization, storm transpositioning, and storm aspect ratio and orientation evaluations. The results of these analyses provide the basis for computing PMP values across
Uploads
Papers by Tye Parzybok