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National Center for Atmospheric Research - NCAR

City
Boulder
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CO

Publications

Coresponding Articles: 68

Articles that are assoicated with National Center for Atmospheric Research - NCAR

Quality Assessment for the National Convective Weather Forecast Product


Authors: Jennifer L. Mahoney · Updated March 15, 2021

Toward Unifying Short-Term and Next-Day Convection-Allowing Ensemble Forecast Systems with a Continuously Cycling 3-km Ensemble Kalman Filter over the Entire Conterminous United States

Using the Weather Research and Forecasting Model, 80-member ensemble Kalman filter (EnKF) analyses with 3-km horizontal grid spacing were produced over the entire conterminous United States (CONUS) for 4 weeks using 1-h continuous cycling. For com...
Authors: Glen S. Romine David C. Dowell Craig S. Schwartz · Updated April 06, 2021

A Progress Report on the Development of the High-Resolution Rapid Refresh Ensemble

The High-Resolution Rapid Refresh Ensemble (HRRRE) is a 36-member ensemble analysis system with 9 forecast members that utilizes the Advanced Research version of the Weather Research and Forecasting (ARW-WRF) dynamic core and the physics suite fro...
Authors: Evan A. Kalina Isidora Jankov Trevor I. Alcott Joseph B. Olson Jeffrey R. Beck David C. Dowell Curtis R. Alexander · Updated May 03, 2021

Evaluation of the Grell–Freitas Convective Scheme in the Hurricane Weather Research and Forecasting (HWRF) Model

The Developmental Testbed Center (DTC) tested two convective parameterization schemes in the Hurricane Weather Research and Forecasting (HWRF) Model and compared them in terms of performance of forecasting tropical cyclones (TCs). Several TC forec...
Authors: Mrinal Biswas Jun A. Zhang Evelyn D. Grell Evan A. Kalina Kathryn M. Newman Ligia R. Bernardet Laurie Carson James T. Frimel Georg A. Grell · Updated May 27, 2021

Impact of the Hydrometeor Vertical Advection Method on HWRF’s Simulated Hurricane Structure

The impact of different hydrometeor advection schemes on TC structure and intensity forecasts is examined through the evaluation of HWRF’s simulation of tropical cyclones using the operational Ferrier–Aligo (FA) microphysics that uses total conden...
Authors: Shaowu Bao Ligia R. Bernardet Greg Thompson Evan A. Kalina Kathryn M. Newman Mrinal Biswas · Updated May 27, 2021

Improving Wind Energy Forecasting through Numerical Weather Prediction Model Development

The primary goal of the Second Wind Forecast Improvement Project (WFIP2) is to advance the state-of-the-art of wind energy forecasting in complex terrain. To achieve this goal, a comprehensive 18-month field measurement campaign was conducted in t...
Authors: Joseph B. Olson Jaymes S. Kenyon David (Dave) D. Turner Michael D. Toy John M. Brown Melinda C. Marquis · Updated April 08, 2021

A scale-dependent blending scheme for WRFDA: impact on regional weather forecasting

Due to limitation of the domain size and limited observations used in regional data assimilation and forecasting systems, regional forecasts suffer a general deficiency in effectively representing large-scale features such as those in global analy...
Authors: Hongli Wang · Updated June 11, 2021

A case study of aerosol data assimilation with the Community Multi-scale Air Quality Model over the contiguous United States using 3D-Var and optimal interpolation methods

This study applies the Gridpoint Statistical Interpolation (GSI) 3D-Var assimilation tool originally developed by the National Centers for Environmental Prediction (NCEP), to improve surface PM2.5 predictions over the contiguous United States (CON...
Authors: Youhua Tang Mariusz Pagowski · Updated September 30, 2021

The Multi-Scale Infrastructure for Chemistry and Aerosols (MUSICA)

To explore the various couplings across space, time and between ecosystems in a consistent manner, atmospheric modeling is moving away from the fractured limited-scale modeling strategy of the past towards a unification of the range of scales inhe...
Authors: Gabriele G. Pfister Georg A. Grell · Updated July 14, 2021

Eye of the Storm: Observing Hurricanes with a Small Unmanned Aircraft System

Unique near-surface observations were collected in hurricanes using a small unmanned aircraft system deployed from NOAA’s hurricane hunter aircraft. Unique data from seven flights of the Coyote small Unmanned Aircraft System (sUAS) were collect...
Authors: Joseph J. Cione Evan A. Kalina · Updated June 22, 2021

Position paper on high performance computing needs in Earth system prediction

The United States experiences some of the most severe weather on Earth. Extreme weather or climate events—such as hurricanes, tornadoes, flooding, drought, and heat waves—can devastate communities and businesses, cause loss of life and property, a...
Authors: Jessie C. Carman Thomas L. Clune Francis Giraldo Mark W. Govett Brian Gross Anke Kamrath Tsengdar Lee David McCarren John Michalakes Scott Sandgathe Timothy R. Whitcomb · Updated June 23, 2021

Recommendations for Developing Useful and Usable Convection-Allowing Model Ensemble Information for NWS Forecasters

U.S. National Weather Service (NWS) forecasters assess and communicate hazardous weather risks, including the likelihood of a threat and its impacts. Convection-allowing model (CAM) ensembles offer potential to aid forecasting by depicting atmosph...
Authors: Julie DeMuth Isidora Jankov Trevor I. Alcott Curtis R. Alexander Daniel Nietfeld Stanley G. Benjamin · Updated July 14, 2021

Impacts of Targeted AERI and Doppler Lidar Wind Retrievals on Short-Term Forecasts of the Initiation and Early Evolution of Thunderstorms

The ability of Atmospheric Emitted Radiance Interferometer (AERI) and Doppler lidar (DL) wind profile observations to impact short-term forecasts of convection is explored by assimilating retrievals into a partially cycled convection-allowing ense...
Authors: Michael C. Coniglio David (Dave) D. Turner · Updated August 11, 2021

Initial Development and Testing of a Convection-Allowing Model Scorecard

Evaluation of numerical weather prediction (NWP) is critical for both forecasters and researchers. Through such evaluation, forecasters can understand the strengths and weaknesses of NWP guidance, and researchers can work to improve NWP models. Ho...
Authors: Burkely T. Gallo Curtis R. Alexander · Updated August 11, 2021

The Impacts of Using Mixed Physics in the Community Leveraged Unified Ensemble

A well-known problem in high-resolution ensembles has been a lack of sufficient spread among members. Modelers often have used mixed physics to increase spread, but this can introduce problems including computational expense, clustering of members...
Authors: William A. Gallus Jeffrey R. Beck · Updated August 11, 2021

Stochastically Perturbed Parameterizations in a HRRR-Based Ensemble

A stochastically perturbed parameterization (SPP) approach that spatially and temporally perturbs parameters and variables in the Mellor-Yamada-Nakanishi-Niino planetary boundary layer scheme (PBL) and introduces initialization perturbations to so...
Authors: Isidora Jankov Jeffrey R. Beck Joseph B. Olson Tatiana (Tanya) R. Smirnova Curtis R. Alexander · Updated August 11, 2021

Systematic Comparison of Convection-Allowing Models during the 2017 NOAA HWT Spring Forecasting Experiment

The 2016–2018 NOAA Hazardous Weather Testbed (HWT) Spring Forecasting Experiments (SFE) featured the Community Leveraged Unified Ensemble (CLUE), a coordinated convection-allowing model (CAM) ensemble framework designed to provide empirical guidan...
Authors: Corey K. Potvin David C. Dowell · Updated August 12, 2021

Helicity Dynamics, Inverse, and Bidirectional Cascades in Fluid and Magnetohydrodynamic Turbulence: A Brief Review

We briefly review helicity dynamics, inverse and bidirectional cascades in fluid and magnetohydrodynamic (MHD) turbulence, with an emphasis on the latter. The energy of a turbulent system, an invariant in the nondissipative case, is transferred to...
Authors: Annick Pouquet Duane Rosenberg · Updated August 12, 2021

Toward a Better Regional Ozone Forecast Over CONUS Using Rapid Data Assimilation of Clouds and Meteorology in WRF-Chem

Accuracy of cloud predictions in numerical weather models can considerably impact ozone (O3) forecast skill. This study assesses the benefits in surface O3 predictions of using the Rapid Refresh (RAP) forecasting system that assimilates clouds as ...
Authors: Young-Hee Ryu Ming Hu · Updated August 12, 2021

Exploring the convective grey zone with regional simulations of a cold air outbreak

Cold air outbreaks can bring snow to populated areas and can affect aviation safety. Shortcomings in the representation of these phenomena in global and regional models are thought to be associated with large systematic cloud-related radiative flu...
Authors: Paul R. Field Joseph B. Olson · Updated September 21, 2021

A Performance Comparison between Multiphysics and Stochastic Approaches within a North American RAP Ensemble

A stochastic parameter perturbation (SPP) scheme consisting of spatially and temporally varying perturbations of uncertain parameters in the Grell–Freitas convective scheme and the Mellor–Yamada–Nakanishi–Niino planetary boundary scheme was develo...
Authors: Isidora Jankov Jeffrey R. Beck hongli jiang Joseph B. Olson Georg A. Grell Tatiana (Tanya) R. Smirnova Stanley G. Benjamin John M. Brown · Updated September 22, 2021

Evaluation of deep convective transport in storms from different convective regimes during the DC3 field campaign using WRF-Chem with lightning data assimilation

Deep convective transport of surface moisture and pollution from the planetary boundary layer to the upper troposphere and lower stratosphere affects the radiation budget and climate. This study analyzes the deep convective transport in three diff...
Authors: Yunyao Li Megan M. Bela · Updated September 22, 2021

The Weather Research and Forecasting Model: Overview, System Efforts, and Future Directions

Since its initial release in 2000, the Weather Research and Forecasting (WRF) Model has become one of the world’s most widely-used numerical weather prediction models. Designed to serve both research and operational needs, it has grown to offer a ...
Authors: Jordan G. Powers Ravan Ahmadov Georg A. Grell Stanley G. Benjamin Curtis R. Alexander · Updated September 28, 2021

Spatial Coverage of Monitoring Networks: A Climate Observing System Simulation Experiment

Observing systems consisting of a finite number of in situ monitoring stations can provide high-quality measurements with the ability to quality assure both the instruments and the data but offer limited information over larger geographic areas. T...
Authors: Elizabeth (Betsy) C. Weatherhead Jason M. English · Updated September 30, 2021

Assimilation of Pseudo-GLM Data Using the Ensemble Kalman Filter

Total lightning observations that will be available from the GOES-R Geostationary Lightning Mapper (GLM) have the potential to be useful in the initialization of convection-resolving numerical weather models, particularly in areas where other type...
Authors: Blake J. Allen David C. Dowell · Updated October 15, 2021

Community HWRF Users' Guide v3.5a August 2013

The Weather Research and Forecast (WRF) system for hurricane prediction (HWRF) is an operational model implemented at the National Centers for Environmental Prediction (NCEP) of the National Weather Service (NWS) to provide numerical guidance to t...
Authors: Ligia R. Bernardet Shaowu Bao timothy P. brown · Updated October 15, 2021

Assessment of the data assimilation framework for the Rapid Refresh Forecast System v0.1 and impacts on forecasts of a convective storm case study

The Rapid Refresh Forecast System (RRFS) is currently under development and aims to replace the National Centers for Environmental Prediction (NCEP) operational suite of regional and convective scale modeling systems in the next upgrade. In order ...
Authors: Ivette H. Banos Guoqing Ge · Updated September 13, 2022

Comparing Partial and Continuously Cycling Ensemble Kalman Filter Data Assimilation Systems for Convection-Allowing Ensemble Forecast Initialization

Several limited-area 80-member ensemble Kalman filter (EnKF) data assimilation systems with 15-km horizontal grid spacing were run over a computational domain spanning the conterminous United States (CONUS) for a 4-week period. One EnKF employed c...
Authors: Craig S. Schwartz David C. Dowell · Updated January 10, 2022

Biases in the Prediction of Convective Storm Characteristics with a Convection Allowing Ensemble

The severity, duration, and spatial extent of thunderstorm impacts are related to convective storm mode. This study assesses the skill of the High-Resolution Rapid Refresh Ensemble (HRRR-E) and its deterministic counterpart (HRRRv4) at predicting ...
Authors: Joseph A. Grim David C. Dowell · Updated January 12, 2022

Hurricane Weather Researchand Forecasting (HWRF) Model:2015 Scientific Documentation

This document describes the scientific aspects of the Hurricane Weather Research and Forecasting (HWRF) modeling system. This is based on 2015 HWRF v3.7a public release. This technical note along with the HWRF v3.7a Users Guide provides the user w...
Authors: Vijay Tallapragada Ligia R. Bernardet · Updated January 25, 2022

An Evaluation of Stochastic Physics Within the High Resolution Rapid Refresh (HRRR) Ensemble and the Impacts of High Performance Computing (HPC)

Lack of spread is a common deficiency in ensemble models and results in over-confident and inaccurate forecasts. A number of options exist to increase the spread of an ensemble, including the use of multiple physics parameterizations or dynamic c...
Authors: Jeffrey R. Beck Isidora Jankov hongli jiang James T. Frimel · Updated January 25, 2022

An Investigation of the Goshen County, Wyoming, Tornadic Supercell of 5 June 2009 Using EnKF Assimilation of Mobile Mesonet and Radar Observations Collected during VORTEX2. Part I: Experiment Design and Verification of the EnKF Analyses

High-resolution Doppler radar velocities and in situ surface observations collected in a tornadic supercell on 5 June 2009 during the second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX2) are assimilated into a simulated...
Authors: James Marquis David C. Dowell · Updated January 26, 2022

An Observing System Simulation Experiment for the Unmanned Aircraft System Data Impact on Tropical Cyclone Track Forecasts

High-altitude, long-endurance Unmanned Aircraft Systems (HALE UAS) are capable of extended flights for atmospheric sampling. A case study was conducted to evaluate the potential impact of dropwindsonde observations from HALE UAS on tropical cyclon...
Authors: nikki prive Yuanfu Xie · Updated January 26, 2022

Analyzing the Grell-Freitas convection scheme from hydrostatic to non hydrostatic scales within a global model

The authors implemented the Grell–Freitas (GF) parameterization of convection in which the cloud-base mass flux varies quadratically as a function of the convective updraft fraction in the global nonhydrostatic Model for Prediction Across Scales (...
Authors: Laura D. Fowler Georg A. Grell · Updated January 26, 2022

Assimilation of wind speed and direction observations: results from real observation experiments

The assimilation of wind observations in the form of speed and direction (asm_sd) by the Weather Research and Forecasting Model Data Assimilation System (WRFDA) was performed using real data and employing a series of cycling assimilation experimen...
Authors: Feng Gao Hongli Wang · Updated January 26, 2022

Bridging Research to Operations Transitions: Status and Plans of Community GSI

With a goal of improving operational numerical weather prediction (NWP), the Developmental Testbed Center (DTC) has been working with operational centers, including, among others, the National Centers for Environmental Prediction (NCEP), National ...
Authors: Hui Shao Ming Hu · Updated January 26, 2022

Community HWRF Users Guide V3.5A

The Weather Research and Forecast (WRF) system for hurricane prediction (HWRF) is an operational model implemented at the National Centers for Environmental Prediction (NCEP) of the National Weather Service (NWS) to provide numerical guidance to t...
Authors: Ligia R. Bernardet Shaowu Bao timothy P. brown · Updated January 27, 2022

Community HWRF Users Guide v3.8a - The Developmental Testbed Center

The Weather Research and Forecast (WRF) system for hurricane prediction (HWRF) is an op-erational model implemented at the National Centers for Environmental Prediction (NCEP)of the National Weather Service (NWS) to provide numerical guidance to t...
Authors: Christina Holt Ligia R. Bernardet · Updated January 27, 2022

Community HWRF Users’ Guide v3.7a

The Weather Research and Forecast (WRF) system for hurricane prediction (HWRF) is an op-erational model implemented at the National Centers for Environmental Prediction (NCEP)of the National Weather Service (NWS) to provide numerical guidance to t...
Authors: Christina Holt Ligia R. Bernardet timothy P. brown · Updated January 27, 2022

Community Support and Transition of Research to Operations for the Hurricane Weather Research and Forecasting Model

The Hurricane Weather Research and Forecasting Model (HWRF) is an operational model used to provide numerical guidance in support of tropical cyclone forecasting at the National Hurricane Center. HWRF is a complex multicomponent system, consisting...
Authors: Ligia R. Bernardet Shaowu Bao timothy P. brown · Updated January 27, 2022

Impact of Assimilating Radiances with the WRFDA ETKF/3DVAR Hybrid System on Prediction of Two Typhoons in 2012

The impacts of AMSU-A and IASI (Infrared Atmospheric Sounding Interferometer) radiances assimilation on the prediction of typhoons Vicente and Saola (2012) are studied by using the ensemble transform Kalman filter/three-dimensional variational (ET...
Authors: Dongmei Xu Hongli Wang · Updated February 14, 2022

Impact of Loss of U.S. Microwave and Radio Occultation Observations in Operational Numerical Weather Prediction in Support of the U.S. Data Gap Mitigation Activities

As the U.S. polar-orbiting satellites NOAA-15, -18, and -19 and NASA’s Aqua satellite reach the ends of their lives, there may be a loss in redundancy between their microwave (MW) soundings, and the Advanced Technology Microwave Sounder (ATMS) on ...
Authors: Lidia Cucurull · Updated February 14, 2022

Inhomogeneous Background Error Modeling for WRF-Var Using the NMC Method

Background error modeling plays a key role in a variational data assimilation system. The National Meteorological Center (NMC) method has been widely used in variational data assimilation systems to generate a forecast error ensemble from which th...
Authors: Hongli Wang Man Zhang · Updated February 14, 2022

North Atlantic simulations in Coordinated Ocean-ice Reference Experiments phase II (CORE-II). Part II: Inter-annual to decadal variability

Simulated inter-annual to decadal variability and trends in the North Atlantic for the 1958–2007 period from twenty global ocean – sea-ice coupled models are presented. These simulations are performed as contributions to the second phase of the Co...
Authors: Gokhan Danabasoglu Rainer Bleck Shan Sun · Updated February 15, 2022

Radar in Atmospheric Sciences and Related Research: Current Systems, Emerging Technology, and Future Needs

To assist the National Science Foundation in meeting the needs of the community of scientists by providing them with the instrumentation and platforms necessary to conduct their research successfully, a meeting was held in late November 2012 with ...
Authors: Howard B. Bluestein David C. Dowell · Updated February 16, 2022

Rapid Mesoscale Environmental Changes Accompanying Genesis of an Unusual Tornado

This study documents a very rapid increase in convective instability, vertical wind shear, and mesoscale forcing leading to the formation of a highly unusual tornado as detected by a ground-based microwave radiometer and wind profiler, and in 1-km...
Authors: steven E. koch hongli jiang Yuanfu Xie · Updated February 16, 2022

Sensitivity of hurricane forecasts to cumulus parameterizations in the HWRF model

The Developmental Testbed Center used the Hurricane Weather Research and Forecasting (HWRF) system to test the sensitivity of tropical cyclone track and intensity forecasts to different convective schemes. A control configuration that employed the...
Authors: Mrinal Biswas Ligia R. Bernardet · Updated February 17, 2022

The Earth System Prediction Suite: Toward a Coordinated U.S. Modeling Capability

The Earth System Prediction Suite (ESPS) is a collection of flagship U.S. weather and climate models and model components that are being instrumented to conform to interoperability conventions, documented to follow metadata standards, and made ava...
Authors: Gerhard Theurich Steven E. Peckham · Updated February 17, 2022

The Mesoscale Predictability Experiment (MPEX)

The Mesoscale Predictability Experiment (MPEX) was conducted from 15 May to 15 June 2013 in the central United States. MPEX was motivated by the basic question of whether experimental, subsynoptic observations can extend convective-scale predictab...
Authors: Morris L. Weisman John M. Brown David C. Dowell · Updated February 18, 2022

The vital need for a climate information system

There is increasing acceptance among the general public that the climate is changing and that it is mainly due to human activities. Scientists have long been aware of this and it has been made clear in the many IPCC assessment reports since the se...
Authors: Kevin E. Trenberth Melinda C. Marquis · Updated February 23, 2022

Thermodynamic and liquid profiling during the 2010 Winter Olympics

Tropospheric observations by a microwave profiling radiometer and six-hour radiosondes were obtained during the Alpine Venue of the 2010 Winter Olympic Games at Whistler, British Columbia, by Environment Canada. The radiometer provided continuous ...
Authors: Randolph H. Ware steve C. albers · Updated February 23, 2022

Variational Assimilation of Cloud Liquid/Ice Water Path and its Impact on NWP

Analysis of the cloud components in numerical weather prediction models using advanced data assimilation techniques has been a prime topic in recent years. In this research, the variational data assimilation (DA) system for the Weather Research an...
Authors: Yaodeng Chen Hongli Wang · Updated February 24, 2022

WRF-Chem Version 3.8.1 Users Guide

The WRF-Chem User's Guide is designed to provide the reader with information specific to the chemistry part of the WRF model and its potential applications. It will provide the user a description of the WRF-Chem model and discuss specific issues r...
Authors: Georg A. Grell Ravan Ahmadov Ka Yee Wong Steven E. Peckham · Updated February 24, 2022

WRF/Chem Version 3.3 User's Guide


Authors: Steven E. Peckham Georg A. Grell · Updated February 25, 2022

A Multi-Time-Scale Four-Dimensional Variational Data Assimilation Scheme and its Application to Simulated Radial Velocity and Reflectivity Data

In this study, a multi-time-scale four-dimensional variational data assimilation (MTS-4DVar) scheme is developed and applied to the assimilation of radar observations. The MTS-4DVar employs multi-time windows with various time-lengths in the frame...
Authors: Tao Sun Hongli Wang · Updated June 11, 2021

Characterizing Changes in Eastern U.S. Pollution Events in a Warming World

Risk assessments of air pollution impacts on human health and ecosystems would ideally consider a broad set of climate and emission scenarios, as well as natural internal climate variability. We analyze initial condition chemistry-climate ensemble...
Authors: Arlene M. Fiore Jordan Schnell · Updated June 02, 2022

Retrievals of Ozone in the Troposphere and Lower Stratosphere Using FTIR Observations Over Greenland

When retrieving geophysical parameters, it is advantageous to have an estimate of prior information that is based on observations with associated uncertainties, but this is often not possible. Long-term ground-based remote sensing measurements and...
Authors: Shima Bahramvash Shams David (Dave) D. Turner · Updated June 17, 2022

Effect of rotation on mixing efficiency in homogeneous stratified turbulence using unforced direct numerical simulations

Diapycnal (irreversible) mixing is analyzed using thirty direct numerical simulations (at 10243 resolution) of homogeneous rotating stratified turbulence (RST) in the absence of imposed shear or forcing. The influence of varied rotation and strati...
Authors: Matthew Klema Duane Rosenberg · Updated June 28, 2022

NSF AI Institute for Research on Trustworthy AI in Weather, Climate, and Coastal Oceanography (AI2ES)

We introduce the National Science Foundation (NSF) AI Institute for Research on Trustworthy AI in Weather, Climate, and Coastal Oceanography (AI2ES). This AI institute was funded in 2020 as part of a new initiative from the NSF to advance foundati...
Authors: Amy McGovern Jebb Q. Stewart · Updated July 19, 2022

Short-Term Convection-Allowing Ensemble Precipitation Forecast Sensitivity to Resolution of Initial Condition Perturbations and Central Initial States

Nine sets of 36-h, 10-member, convection-allowing ensemble (CAE) forecasts with 3-km horizontal grid spacing were produced over the conterminous United States for a 4-week period. These CAEs had identical configurations except for their initial co...
Authors: Craig S. Schwartz David C. Dowell · Updated July 19, 2022

The Evolving Role of Humans in Weather Prediction and Communication

A series of webinars and panel discussions were conducted on the topic of the evolving role of humans in weather prediction and communication, in recognition of the 100th anniversary of the founding of the AMS. One main theme that arose was the in...
Authors: Neil A. Stuart Daniel Nietfeld · Updated August 09, 2022

The Common Community Physics Package (CCPP) Framework v6

The Common Community Physics Package (CCPP) is a collection of atmospheric physical parameterizations for use in Earth system models and a framework that couples the physics to a host model’s dynamical core. A primary goal for this effort is to fa...
Authors: Dominikus Heinzeller Ligia R. Bernardet Grant Firl Man Zhang Xia Sun · Updated March 28, 2023

Proceedings of the 2023 Improving Scientific Software Conference

The Software Engineering Assembly (SEA) is a loosely structured group of software engineers and scientists who write scientific software, mostly but not only at NCAR and mostly but not only in the field of atmospheric sciences. The mission of the ...
Authors: Christina Holt · Updated August 22, 2023

Competing Forecast Verification: Using the Power-Divergence Statistic for Testing the Frequency of “Better

When testing hypotheses about which of two competing models is better, say A and B, the difference is often not significant. An alternative, complementary approach, is to measure how often model A is better than model B regardless of how slight or...
Authors: David (Dave) D. Turner Eric Gilleland Domingo Muñoz-Esparza · Updated August 22, 2023

Improving the Representation of Hail in the Thompson Microphysics Scheme

Methods to improve the representation of hail in the Thompson–Eidhammer microphysics scheme are explored. A new two-moment and predicted density graupel category is implemented into the Thompson–Eidhammer scheme. Additionally, the one-moment graup...
Authors: Anders Jensen Gregory Thompson Kyoko Ikeda Sarah Tessendorf · Updated December 27, 2023

The Prediction of Supercooled Large Drops by a Microphysics and a Machine Learning Model for the ICICLE Field Campaign

The prediction of supercooled large drops (SLD) from the Thompson–Eidhammer (TE) microphysics scheme—run as part of the High-Resolution Rapid Refresh (HRRR) model—is evaluated with observations from the In-Cloud Icing and Large drop Experiment (IC...
Authors: Anders Jensen Courtney Weeks Mei Xu Scott Landolt Alexei Korolev Mengistu Wolde Stephanie DiVito · Updated December 27, 2023

Envisioning the Future of Community Physics

A large cadre of physics developers, model developers interested in physics-dynamics coupling, code managers, computational scientists met virtually for the Common Community Physics Package (CCPP) Visioning Workshop to discuss the current status a...
Authors: Grant Firl Ligia R. Bernardet Lulin Xue Dustin Swales Laura D. Fowler Courtney Peverly Ming Xue Fanglin Yang · Updated September 13, 2024

Assessing RRFS versus HRRR in Predicting Widespread Convective Systems over the Eastern CONUS

This study provides a comparison of the operational HRRR version 4 and its eventual successor, the experimental Rapid Refresh Forecast System (RRFS) model (summer 2022 version), at predicting the evolution of convective storm characteristics durin...
Authors: Joseph A. Grim James Pinto David C. Dowell · Updated April 02, 2024