Reproducing the September 2013 Record-Breaking Rainfall over the Colorado Front Range with High-Resolution WRF Forecasts

2014 ◽  
Vol 29 (2) ◽  
pp. 393-402 ◽  
Author(s):  
Craig S. Schwartz
Keyword(s):  
High Resolution ◽  
Initial Conditions ◽  
Rainfall Event ◽  
Colorado Front Range ◽  
Weather Research And Forecasting ◽  
Forecasting Model ◽  
Front Range ◽  
Torrential Rainfall ◽  
Horizontal Grid ◽  
Sensitivity To Initial Conditions

Abstract Four convection-permitting Weather Research and Forecasting Model (WRF) forecasts were produced in an attempt to replicate the record-breaking rainfall across the Colorado Front Range between 1200 UTC 11 September and 1200 UTC 13 September 2013. A nested WRF domain with 4- and 1-km horizontal grid spacings was employed, and sensitivity to initial conditions (ICs) and microphysics (MP) parameterizations was examined. Rainfall forecasts were compared to gridded observations produced by National Weather Service River Forecast Centers and gauge measurements from the Community Collaborative Rain, Hail and Snow Network (CoCoRaHS). All 1-km forecasts produced 48-h rainfall exceeding 250 mm over portions of the Colorado Front Range and were more consistent with observations than the 4-km forecasts. While localized sensitivities to both ICs and MP were noted, systematic differences were not attributable to the varied ICs or MP schemes. At times, the 1-km forecasts produced precipitation structures similar to those observed, but none of the forecasts successfully captured the observed mesoscale evolution of the entire rainfall event. Nonetheless, as all 1-km forecasts produced torrential rainfall over the Colorado Front Range, these forecasts could have been useful guidance for this event.

scholarly journals Sources and Characteristics of Summertime Organic Aerosol in the Colorado Front Range: Perspective from Measurements and WRF-Chem Modeling

2018 ◽  
Author(s):  
Roya Bahreini ◽  
Ravan Ahmadov ◽  
Stu A. McKeen ◽  
Kennedy T. Vu ◽  
Justin H. Dingle ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Organic Aerosol ◽  
Colorado Front Range ◽  
Weather Research And Forecasting ◽  
Front Range ◽  
Top Down ◽  
Mixing Ratios ◽  
Oil And Natural Gas ◽  
The Mean

Abstract. Evolution of organic aerosol (OA) and their precursors in the boundary layer of Colorado Front Range during the Front Range Air Pollution and Photochemistry Éxperiment (FRAPPÉ, July–August 2014) was analyzed by in-situ measurements and chemical transport modeling. Measurements indicated significant production of secondary OA (SOA), with enhancement ratio of OA with respect to carbon monoxide (CO) reaching 0.068 ± 0.004 μg m−3 ppbv−1. At background mixing ratios of CO, up to ~ 2 μg m−3 background OA was observed, suggesting significant non-combustion contribution to OA in the Front Range. The mean concentration of OA in plumes with a high influence of oil and natural gas (O&G) emissions was ~ 40 % higher than in urban-influenced plumes. Positive matrix factorization confirmed a dominant contribution of secondary, oxygenated OA (OOA) in the boundary layer instead of fresh, hydrocarbon-like OA (HOA). Combinations of primary OA (POA) volatility assumptions, aging of semi-volatile species, and different emission estimates from the O&G sector were used in the Weather Research and Forecasting model, coupled with Chemistry (WRF-Chem) simulation scenarios. The assumption of semi-volatile POA resulted in greater than a factor of 10 lower POA concentrations compared to PMF-resolved HOA. Including a top-down modified O&G emissions resulted in substantially better agreements in modeled ethane, toluene, hydroxyl radical, and ozone compared to measurements in the high O&G-influenced plumes. By including emissions from the O&G sector using the top-down approach, it was estimated that the O&G sector contributed to

scholarly journals High-resolution fire danger forecast for Poland based on the Weather Research and Forecasting Model

2021 ◽  
Author(s):  
Alan Mandal ◽  
Grzegorz Nykiel ◽  
Tomasz Strzyzewski ◽  
Adam Kochanski ◽  
Weronika Wrońska ◽  
...  
Keyword(s):  
High Resolution ◽  
Fire Danger ◽  
Weather Research And Forecasting ◽  
Forecasting Model ◽  
Weather Research

scholarly journals Evaluation of Weather Research and Forecasting Model (WRF) Simulations over Middle East

2018 ◽  
Vol 29 (2) ◽  
pp. 26
Author(s):  
Thaer Obaid Roomi
Keyword(s):  
Middle East ◽  
Initial Conditions ◽  
Wrf Model ◽  
Weather Research And Forecasting ◽  
Forecasting Model ◽  
Data Sets ◽  
Wind Speeds ◽  
Computing Skills ◽  
Predicted Values ◽  
Weather Research

The Weather Research and Forecasting model (WRF) is an atmospheric simulation system designed for both research and operational applications. This worldwide used model requires a sophisticated modeling experience and computing skills. In this study, WRF model was used to predict many atmospheric parameters based on the initial conditions extracted from NOMADS data sets. The study area is basically the region surrounded by the longitudes and latitudes: 15o-75o E and 10.5o-45o N which typically includes the Middle East region. The model was installed on Linux platform with a grid size of 10 km in the X and Y directions. A low pressure trough was tracked in its movement from west to east via the Middle East during the period from 1 to 7 January 2010 as a case study of the WRF model. MATLAB and NCAR Command Language (NCL) were used to display the model output. To evaluate the forecasted parameters and patterns, some comparisons were made between the predicted and actual weather charts. Wind speeds and directions in the prognostic and actual charts of 700 hPa were in agreement. However, the predicted values of geopotential heights in WRF are somewhat overestimate the actual ones. This may be attributed to the differences in the data sources and data analysis methods of the two data agencies, NOMADS and ECMWF.

scholarly journals Warning Information in a Preconvection Environment from the Geostationary Advanced Infrared Sounding System—A Simulation Study Using the IHOP Case

2011 ◽  
Vol 50 (3) ◽  
pp. 776-783 ◽  
Author(s):  
Jun Li ◽  
Jinlong Li ◽  
Jason Otkin ◽  
Timothy J. Schmit ◽  
Chian-Yi Liu
Keyword(s):  
High Resolution ◽  
Simulation Study ◽  
Model Simulation ◽  
Weather Research And Forecasting ◽  
Forecasting Model ◽  
High Temporal Resolution ◽  
Potential Utility ◽  
Convective Initiation ◽  
System A ◽  
Atmospheric Data

Abstract In this paper, a convective initiation event from the International H2O Project (IHOP) field experiment is used to demonstrate the potential utility of a future geostationary advanced infrared (IR) sounder for severe storm nowcasting applications. An advanced IR sounder would provide detailed stability information (e.g., lifted index and other parameters) with high temporal resolution useful for determining favorable locations for convective initiation. Atmospheric data from a high-resolution Weather Research and Forecasting model simulation was used to generate simulated Hyperspectral Environmental Suite (HES) and Advanced Baseline Imager (ABI) stability products. Comparison of these products shows that the ABI [or the current Geostationary Operational Environmental Satellite (GOES) Sounder] provides limited stability information before the storm development as a result of the limited spectral IR information for temperature and moisture profiling. The high spatial and temporal geostationary advanced IR sounder, however, can provide critical information about the destabilization much earlier than the current GOES Sounder or ABI.

Sign in / Sign up

Export Citation Format

Share Document