Weather and Forecasting最新文献_第9页

Developing a Hail and Wind Damage Swath Event Database from Daily MODIS True Color Imagery and Storm Reports for Impact Analysis and Applications 从每日MODIS真彩色图像和风暴报告中开发冰雹和风力损害事件数据库，用于影响分析和应用

IF 2.9 3区地球科学

Weather and Forecasting Pub Date : 2023-06-23 DOI: 10.1175/waf-d-22-0210.1

J. Bell, Emily F. Wisinski, A. Molthan, C. Schultz, Emma Gilligan, Kaylee G. Sharp

{"title":"Developing a Hail and Wind Damage Swath Event Database from Daily MODIS True Color Imagery and Storm Reports for Impact Analysis and Applications","authors":"J. Bell, Emily F. Wisinski, A. Molthan, C. Schultz, Emma Gilligan, Kaylee G. Sharp","doi":"10.1175/waf-d-22-0210.1","DOIUrl":"https://doi.org/10.1175/waf-d-22-0210.1","url":null,"abstract":"\u0000Hail and damaging winds are two threats associated with intense and severe thunderstorms that traverse the Midwest and Great Plains during the primary growing season. In certain severe thunderstorm events, large swaths of agricultural crops are impacted, allowing the damage to be viewed from multiple satellite remote sensing platforms. Previous studies have focused on analyzing individual hail and wind damage swaths (HWDSs) using satellite remote sensing, but these swaths have never been officially archived or documented. This lack of documentation has made it difficult to analyze the spatial extent and temporal frequency of HWDSs from year to year. This study utilizes daily true color imagery from MODIS aboard NASA’s Terra and Aqua satellites and daily local storm reports from the Storm Prediction Center to build a database of HWDSs occurring in the months of May through August, for years 2000 through 2020. This database identified 1,646 HWDSs in 12 states throughout the Midwest and Great Plains, confirmed through a combination of archived severe weather warnings, radar information, and official storm reports. For each entry in the HWDS database, a geospatial outline is provided along with the most likely date of first visible damage from MODIS imagery as well as the physical characteristics and time of occurrence estimated from available warnings. This study also provides a summary of the radar characteristics for a portion of the database. This database will further the understanding of severe weather damage by hail and wind to agriculture to help understand the frequency of these events and assist in mapping the impacted areas.","PeriodicalId":49369,"journal":{"name":"Weather and Forecasting","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47339631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Competing Forecast Verification: Using the Power-Divergence Statistic for Testing the Frequency of “Better” 竞争预测验证:用功率发散统计量检验“更好”的频率

IF 2.9 3区地球科学

Weather and Forecasting Pub Date : 2023-06-21 DOI: 10.1175/waf-d-22-0201.1

E. Gilleland, D. Muñoz‐Esparza, David D. Turner

{"title":"Competing Forecast Verification: Using the Power-Divergence Statistic for Testing the Frequency of “Better”","authors":"E. Gilleland, D. Muñoz‐Esparza, David D. Turner","doi":"10.1175/waf-d-22-0201.1","DOIUrl":"https://doi.org/10.1175/waf-d-22-0201.1","url":null,"abstract":"\u0000When 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 large the difference. The hypothesis concerns whether or not the percentage of time that model A is better than model B is larger than 50%. One generalized test statistic that can be used is the power-divergence test, which encompasses many familiar goodness-of-fit test statistics, such as the loglikelihood-ratio and Pearson X2 tests. Theoretical results justify using the distribution for the entire family of test statistics, where k is the number of categories. However, these results assume that the underlying data are independent and identically distributed; which is often violated. Empirical results demonstrate that the reduction to two categories (i.e., model A is better than model B v. model B is better than A) results in a test that is reasonably robust to even severe departures from temporal independence, as well as contemporaneous correlation. The test is demonstrated on two different example verification sets: 6-h forecasts of eddy dissipation rate (m2/3s−1) from two versions of the Graphical Turbulence Guidence model and for 12-hour forecasts of 2-m temperature (°C) and 10-m wind speed (ms−1) from two versions of the High-Resolution Rapid Refresh model. The novelty of this paper is in demonstrating the utility of the power-divergence statistic in the face of temporally dependent data, as well as the emphasis on testing for the “frequency-of-better” alongside more traditional measures.","PeriodicalId":49369,"journal":{"name":"Weather and Forecasting","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43807925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Intensification of Hurricane Sally (2020) over the Mississippi River plume 飓风莎莉（2020）在密西西比河羽流上空增强

IF 2.9 3区地球科学

Weather and Forecasting Pub Date : 2023-06-16 DOI: 10.1175/waf-d-22-0191.1

Effy B John, K. Balaguru, L. Leung, G. Foltz, R. Hetland, S. Hagos

{"title":"Intensification of Hurricane Sally (2020) over the Mississippi River plume","authors":"Effy B John, K. Balaguru, L. Leung, G. Foltz, R. Hetland, S. Hagos","doi":"10.1175/waf-d-22-0191.1","DOIUrl":"https://doi.org/10.1175/waf-d-22-0191.1","url":null,"abstract":"\u0000Tropical Cyclone (TC) Sally formed on September 11, 2020, traveled through the Gulf of Mexico (GMX), and intensified rapidly before making landfall on the Alabama coast as a devastating Category 2 TC with extensive coastal and inland flooding. In this study, using a combination of observations and idealized numerical model experiments, we demonstrate that the Mississippi River plume played a key role in the intensification of Sally near the northern Gulf coast. As the storm intensified and its translation slowed before landfall, sea surface cooling was reduced along its track, coincident with a pronounced increase in SSS. Further analysis reveals that TC Sally encountered a warm Loop Current eddy in the northern GMX close to the Mississippi River plume. Besides deepening the thermocline, the eddy advected low salinity Mississippi River plume water into the storm’s path. This resulted in the development of strong upper-ocean salinity stratification, with a shallow layer of fresh water lying above a deep, warm ‘barrier layer’. Consequently, TC-induced mixing and the associated sea surface cooling were reduced, aiding Sally’s intensification. These results suggest that the Mississippi River plume and freshwater advection by the Loop Current can play an important role in TC intensification near the US Gulf coast.","PeriodicalId":49369,"journal":{"name":"Weather and Forecasting","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49627678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Advancing Tropical Cyclone Precipitation Forecast Verification Methods and Tools 热带气旋降水预报验证方法和工具的进展

IF 2.9 3区地球科学

Weather and Forecasting Pub Date : 2023-06-15 DOI: 10.1175/waf-d-23-0001.1

Kathryn M. Newman, B. Brown, John Halley Gotway, L. Bernardet, M. Biswas, T. Jensen, L. Nance

{"title":"Advancing Tropical Cyclone Precipitation Forecast Verification Methods and Tools","authors":"Kathryn M. Newman, B. Brown, John Halley Gotway, L. Bernardet, M. Biswas, T. Jensen, L. Nance","doi":"10.1175/waf-d-23-0001.1","DOIUrl":"https://doi.org/10.1175/waf-d-23-0001.1","url":null,"abstract":"\u0000Tropical cyclone (TC) forecast verification techniques have traditionally focused on track and intensity, as these are some of the most important characteristics of TCs and are often the principle verification concerns of operational forecast centers. However, there is a growing need to verify other aspects of TCs as process-based validation techniques may be increasingly necessary for further track and intensity forecast improvements as well as improving communication of the broad impacts of TCs including inland flooding from precipitation. Here we present a set of TC-focused verification methods available via the Model Evaluation Tools (MET) ranging from traditional approaches, to the application of storm-centric coordinates and the use of feature-based verification of spatially-defined TC objects.\u0000Storm-relative verification using observed and forecast tracks can be useful for identifying model biases in precipitation accumulation in relation to the storm center. Using a storm-centric cylindrical coordinate system based on the radius of maximum wind adds additional storm-relative capabilities to regrid precipitation fields onto cylindrical or polar coordinates. This powerful process-based model diagnostic and verification technique provides a framework for improved understanding of feedbacks between forecast tracks, intensity, and precipitation distributions. Finally, object-based verification including land masking capabilities provides even more nuanced verification options. Precipitation objects of interest, either the central core of TCs or extended areas of rainfall after landfall, can be identified, matched to observations, and quickly aggregated to build meaningful spatial and summary verification statistics.","PeriodicalId":49369,"journal":{"name":"Weather and Forecasting","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45327973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assimilation of AMSU-A Surface-Sensitive Channels in CMA_GFS 4D-Var System over Land CMA_GFS 4D-Var系统对AMSU-A地表敏感通道的陆地同化

IF 2.9 3区地球科学

Weather and Forecasting Pub Date : 2023-06-14 DOI: 10.1175/waf-d-23-0032.1

Hongyi Xiao, Juan Li, Guiqing Liu, Liwen Wang, Yihong Bai

{"title":"Assimilation of AMSU-A Surface-Sensitive Channels in CMA_GFS 4D-Var System over Land","authors":"Hongyi Xiao, Juan Li, Guiqing Liu, Liwen Wang, Yihong Bai","doi":"10.1175/waf-d-23-0032.1","DOIUrl":"https://doi.org/10.1175/waf-d-23-0032.1","url":null,"abstract":"\u0000The assimilation of two surface-sensitive channels of the AMSU-A instruments onboard the NOAA-15/-18/-19 and MetOp-A/B satellites over land was achieved in the China Meteorological Administration Global Forecast System (CMA_GFS). The land surface emissivity was calculated by (1) the window channel retrieval method and (2) the Tool to Estimate Land Surface Emissivities at Microwave frequencies (TELSEM2). Quality controls for these satellite microwave observations over land were conducted. The predictors and regression coefficients used for oceanic satellite data were retained during the bias correction over land and found to perform well. Three batch experiments were implemented in CMA_GFS with 4D-Var: (1) assimilating only the default data, and adding the above data over land with land surface emissivity obtained from (2) TELSEM2 and (3) the window channel retrieval method. The results indicated that the window channel retrieval method can better reduce the departure between the observed and simulated brightness temperature. Over most land types, the positive impacts of this method exceed those of TELSEM2. Both TELSEM2 and the window channel retrieval method improve the humidity analysis near the ground, as well as the forecast capability globally, particularly in those regions where the land coverage is greater, such as in the Northern Hemisphere. The data utilization of the two surface-sensitive channels increase by 6% and 12%, respectively, and the additional data every six hours can cover most land, where there was no surface-sensitive data assimilated before. This study marks the beginning of near-surface channel assimilation over land in CMA_GFS and represents a breakthrough in the assimilation of other surface-sensitive channels in other satellite instruments.","PeriodicalId":49369,"journal":{"name":"Weather and Forecasting","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43538795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The quagmire of arrested development in tropical cyclones 热带气旋发展停滞的泥潭

IF 2.9 3区地球科学

Weather and Forecasting Pub Date : 2023-06-13 DOI: 10.1175/waf-d-22-0194.1

C. Slocum, J. Knaff

{"title":"The quagmire of arrested development in tropical cyclones","authors":"C. Slocum, J. Knaff","doi":"10.1175/waf-d-22-0194.1","DOIUrl":"https://doi.org/10.1175/waf-d-22-0194.1","url":null,"abstract":"\u0000Forty-eight hour intensity forecasts for Hurricane Pamela (2021) from numerical weather prediction models, statistical–dynamical aids, and forecasters were a major forecast bust with Pamela making landfall as a minor rather than major hurricane. From the satellite presentation, Pamela exhibited a symmetric pattern referred to as central cold cover (CCC) in the subjective Dvorak intensity technique. Per the technique, the CCC pattern is accompanied by arrested development in intensity despite the seemingly favorable convective signature. To understand forecast uncertainty during occurrences, central cold cover frequency from 2011–2021 is documented. From these cases, composites of longwave infrared brightness temperatures from geostationary satellites for CCC cases are presented and the surrounding tropical cyclone large-scale environment is quantified and compared with other tropical cyclones at similar latitudes and intensities. These composites show that central cold cover has a consistent presentation, but varies in the preceding hours for storms that eventually intensify or weaken. And, the synoptic-scale environment surrounding the tropical cyclone thermodynamically supports the vigorous deep convection associated with CCC. Finally, intensity forecast errors from numerical weather prediction models and statistical–dynamical aids are examined in comparison to similar tropical cyclones. This work shows that guidance struggles during CCC cases with intensity errors from these models being in the lowest percentiles of performance, particularly for 24- and 36-h forecasts.","PeriodicalId":49369,"journal":{"name":"Weather and Forecasting","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47344214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The roles of chaos seeding and multiple perturbations in convection–permitting ensemble forecasting over southern China 混沌播种和多重扰动在华南对流集合预报中的作用

IF 2.9 3区地球科学

Weather and Forecasting Pub Date : 2023-06-06 DOI: 10.1175/waf-d-22-0177.1

Jingzhuo Wang, Jing Chen, Hongqi Li, Haile Xue, Zhizhen Xu

{"title":"The roles of chaos seeding and multiple perturbations in convection–permitting ensemble forecasting over southern China","authors":"Jingzhuo Wang, Jing Chen, Hongqi Li, Haile Xue, Zhizhen Xu","doi":"10.1175/waf-d-22-0177.1","DOIUrl":"https://doi.org/10.1175/waf-d-22-0177.1","url":null,"abstract":"\u0000The roles of chaos seeding and multiple perturbations, including model perturbations and topographic perturbations, in convection-permitting ensemble forecasting, are assessed. Six comparison experiments were conducted for fourteen heavy rainfall events over southern China. Chaos seeding was run as a benchmark experiment to compare their effects to the intended perturbations. The results first reveal the chaos seeding phenomenon. That is, the tiny and local perturbations of the skin soil moisture propagate into the whole analysis domain within an hour and expand to every prognostic variables, and the perturbations derived from chaos seeding develop when moist convection is active. Secondly, the chaos seeding has the statistically significant differences from our intended perturbations for the ensemble spread magnitudes of precipitation and the spread-skill relationships and probabilistic forecast skills of dynamical variables. Additionally, for the probabilistic forecasts of precipitation, initial and lateral boundary perturbations and model perturbations can yield statistically larger FSS and AROC scores than chaos seeding; topographic perturbations can only improve FSS and AROC scores a little. The different performances may be related to the different degrees of the real dynamical influence of our intended perturbations. Finally, model perturbations can increase the ensemble spreads of precipitation, and improve FSS and AROC scores of precipitation and the consistency of middle- and low-level dynamical variables. However, the effects of topographic perturbations are small.","PeriodicalId":49369,"journal":{"name":"Weather and Forecasting","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46989269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Evaluating the precipitation biases over the western periphery of the Sichuan Basin by ECMWF operational forecast model ECMWF运行预报模型对四川盆地西缘降水偏误的评价

IF 2.9 3区地球科学

Weather and Forecasting Pub Date : 2023-06-05 DOI: 10.1175/waf-d-22-0218.1

Juan Li, Haoming Chen, Puxi Li, Xingwen Jiang

{"title":"Evaluating the precipitation biases over the western periphery of the Sichuan Basin by ECMWF operational forecast model","authors":"Juan Li, Haoming Chen, Puxi Li, Xingwen Jiang","doi":"10.1175/waf-d-22-0218.1","DOIUrl":"https://doi.org/10.1175/waf-d-22-0218.1","url":null,"abstract":"\u0000Based on the hourly merged precipitation product, the performance of the European Centre for Medium-Range Weather Forecasts (ECMWF) Integrated Forecasting System (IFS) in simulating the diurnal variations of precipitation during warm season over the western periphery of the SCB has been evaluated, and the underlying physical causes associated with the wet biases have also been investigated. The results show that the IFS well reproduces the spatial distributions of precipitation amount, frequency, intensity over the SCB, as well as their diurnal variations, but the simulated precipitation peaks earlier than the observation with notable wet biases over the western periphery of the SCB. In addition, the strong wet biases exhibit notable regional difference over the western periphery of the SCB. The simulated wet biases over the southwestern periphery of the SCB expanding westward to higher altitudes along the windward slope, with the maximum wet biases occurring at night. The westward expansion of the simulated stronger upward motions results in a westward shift of precipitation. However, the simulated precipitation over the northwestern periphery of the SCB have small difference in terms of the location, the overestimated precipitation is associated with the stronger atmospheric instability, resulting from the higher potential temperature and the larger specific humidity near the surface. The findings revealed in this study indicate that the ECMWF forecast shows distinct uncertainties over the different complex terrain, and thus offer a promising way forward for improvements of model physical processes.","PeriodicalId":49369,"journal":{"name":"Weather and Forecasting","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44559906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Seasonal forecasting of precipitation, temperature, and snow mass over the western U.S. by combining ensemble post-processing with empirical ocean-atmosphere teleconnections 结合集合后处理和经验海洋-大气遥相关对美国西部降水、温度和雪量的季节预报

IF 2.9 3区地球科学

Weather and Forecasting Pub Date : 2023-06-02 DOI: 10.1175/waf-d-22-0099.1

W. Scheftic, X. Zeng, M. Brunke

{"title":"Seasonal forecasting of precipitation, temperature, and snow mass over the western U.S. by combining ensemble post-processing with empirical ocean-atmosphere teleconnections","authors":"W. Scheftic, X. Zeng, M. Brunke","doi":"10.1175/waf-d-22-0099.1","DOIUrl":"https://doi.org/10.1175/waf-d-22-0099.1","url":null,"abstract":"\u0000Accurate and reliable seasonal forecasts are important for water and energy supply management. Recognizing the important role of snow water equivalent (SWE) for water management, here we include the seasonal forecast of SWE in addition to precipitation (P) and 2-m temperature (T2m) over hydrologically defined regions of the western U.S. A two-stage process is applied to seasonal predictions from two models (NCEP CFSv2 and ECMWF SEAS5) through 1) post-processing to remove biases in the mean, variance, and ensemble spread, and 2) further reducing the residual errors by linear regression using climate indices. The adjusted forecasts from the two models are combined to form a super-ensemble using weights based on their prior skill. The adjusted forecasts are consistently improved over raw model forecasts probabilistically for all variables and deterministically for SWE forecasts. Overall skill of the super-ensemble usually improves upon the skill of forecasts from individual models, however the percentage of seasons and regions with increased skill was approximately the same as those with decreased skill relative to the top performing post-processed individual model. Seasonal SWE has the highest prediction skill, followed by T2m, with P showing lower prediction skill. Persistence contributes strongly to the skill of SWE and moderately to the skill of T2m. Furthermore, a distinct seasonality in the skill is seen in SWE, with a higher skill from late spring through early summer.","PeriodicalId":49369,"journal":{"name":"Weather and Forecasting","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44683878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Challenges in Numerical Weather Prediction of the 10 August 2020 Midwestern Derecho: Examples from the FV3-LAM 2020年8月10日中西部Derecho数值天气预报的挑战:来自FV3-LAM的例子

IF 2.9 3区地球科学

Weather and Forecasting Pub Date : 2023-06-01 DOI: 10.1175/waf-d-23-0019.1

W. Gallus, M. Harrold

{"title":"Challenges in Numerical Weather Prediction of the 10 August 2020 Midwestern Derecho: Examples from the FV3-LAM","authors":"W. Gallus, M. Harrold","doi":"10.1175/waf-d-23-0019.1","DOIUrl":"https://doi.org/10.1175/waf-d-23-0019.1","url":null,"abstract":"\u0000A severe derecho impacted the Midwestern United States on 10 August 2020, causing over 12 billion dollars in damage, and producing peak winds estimated at 63 m s−1, with the worst impacts in Iowa. The event was not forecast well by operational forecasters, nor even by operational and quasi-operational convection-allowing models.\u0000In the present study, nine simulations are performed using the Limited Area Model version of the Finite-Volume-Cubed-Sphere model (FV3-LAM) with three horizontal grid spacings and two physics suites. In addition, when a prototype of the Rapid Refresh Forecast System (RRFS) physics is used, sensitivity tests are performed to examine the impact of using the Grell-Freitas (GF) convective scheme.\u0000Several unusual results are obtained. With both the RRFS (not using GF) and Global Forecast System (GFS) physics suites, simulations using relatively coarse 13 and 25 km horizontal grid spacing do a much better job of showing an organized convective system in Iowa during the daylight hours of 10 August than the 3-km grid spacing runs. In addition, the RRFS run with 25-km grid spacing becomes much worse when the GF convective scheme is used. The 3-km RRFS run that does not use the GF scheme develops spurious nocturnal convection the night before the derecho, removing instability and preventing the derecho from being simulated at all. When GF is used, the spurious storms are removed and an excellent forecast is obtained with an intense bowing echo, exceptionally strong cold pool, and roughly 50 m s−1 surface wind gusts.","PeriodicalId":49369,"journal":{"name":"Weather and Forecasting","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46566288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1