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framework mimicking that of the operational North American Mesoscale Forecast System (NAM), McCarty et al. (2009) showed at 48 h a forecast improvement in geopotential height at 500 hPa, defined as the time difference in hours at which the forecasts fall below two points of equal anomaly correction, is 2.3 h. They also showed improvement of 8% and 7% in equitable threat and bias scores of precipitation forecasts of 25 mm (6 h) −1 . Using a similar framework, Lim et al. (2014) showed improvement in
framework mimicking that of the operational North American Mesoscale Forecast System (NAM), McCarty et al. (2009) showed at 48 h a forecast improvement in geopotential height at 500 hPa, defined as the time difference in hours at which the forecasts fall below two points of equal anomaly correction, is 2.3 h. They also showed improvement of 8% and 7% in equitable threat and bias scores of precipitation forecasts of 25 mm (6 h) −1 . Using a similar framework, Lim et al. (2014) showed improvement in
well. Acknowledgments We are grateful to Dr. Edward Tollerud of the Forecast Systems Laboratory for providing the dataset with MCC times and locations. REFERENCES Anderson, C. J., and R. W. Arritt, 1998: Mesoscale convective complexes and persistent elongated convective systems over the United States during 1992 and 1993. Mon. Wea. Rev., 126, 578–599. 10.1175/1520-0493(1998)126<0578:MCCAPE>2.0.CO;2 Augustine, J. A., and K. W. Howard, 1988: Mesoscale convective complexes over the United States
well. Acknowledgments We are grateful to Dr. Edward Tollerud of the Forecast Systems Laboratory for providing the dataset with MCC times and locations. REFERENCES Anderson, C. J., and R. W. Arritt, 1998: Mesoscale convective complexes and persistent elongated convective systems over the United States during 1992 and 1993. Mon. Wea. Rev., 126, 578–599. 10.1175/1520-0493(1998)126<0578:MCCAPE>2.0.CO;2 Augustine, J. A., and K. W. Howard, 1988: Mesoscale convective complexes over the United States
of this paper. In the few studies that exist in the literature, the quality of the wind radii estimates provided in the TC vitals has been found to have an impact on TC-focused NWP forecasts. For example, Kunii (2015) found that the inclusion of wind radii data helped improve TC track forecasts in the Japan Meteorological Agency’s (JMA) operational mesoscale model. Also, Marchok et al. (2012) showed that modifying the observed 34- and 50-kt wind radii used to initialize the GFDL hurricane
of this paper. In the few studies that exist in the literature, the quality of the wind radii estimates provided in the TC vitals has been found to have an impact on TC-focused NWP forecasts. For example, Kunii (2015) found that the inclusion of wind radii data helped improve TC track forecasts in the Japan Meteorological Agency’s (JMA) operational mesoscale model. Also, Marchok et al. (2012) showed that modifying the observed 34- and 50-kt wind radii used to initialize the GFDL hurricane
; Thorarinsdottir and Gneiting 2010 ; Thorarinsdottir and Johnson 2012 ). However, in many of the aforementioned applications it is important to honor the full information about the bivariate structure of the future wind vector that is provided by the ensemble. Thus, our EMOS postprocessed forecasts take the form of elliptically symmetric bivariate normal densities, as illustrated in Fig. 1 in an application to the University of Washington Mesoscale Ensemble (UWME; Eckel and Mass 2005 ). A description of
; Thorarinsdottir and Gneiting 2010 ; Thorarinsdottir and Johnson 2012 ). However, in many of the aforementioned applications it is important to honor the full information about the bivariate structure of the future wind vector that is provided by the ensemble. Thus, our EMOS postprocessed forecasts take the form of elliptically symmetric bivariate normal densities, as illustrated in Fig. 1 in an application to the University of Washington Mesoscale Ensemble (UWME; Eckel and Mass 2005 ). A description of
frontogenesis northwest of the surface cyclone ( Fig. 1b ). These results are also consistent with the case study work of Martin (1998a , b ), Banacos (2003) , and Moore et al. (2005) , who have documented similar synoptic and mesoscale flow evolutions in case studies of mesoscale banding in the central and eastern United States. These emerging conceptual models of the synoptic and mesoscale flow environments conducive to band formation are providing forecasters with an awareness of the potential for
frontogenesis northwest of the surface cyclone ( Fig. 1b ). These results are also consistent with the case study work of Martin (1998a , b ), Banacos (2003) , and Moore et al. (2005) , who have documented similar synoptic and mesoscale flow evolutions in case studies of mesoscale banding in the central and eastern United States. These emerging conceptual models of the synoptic and mesoscale flow environments conducive to band formation are providing forecasters with an awareness of the potential for
that can be resolved at convection-allowing model resolutions. For example, the number of mesoscale surface observation networks (i.e., mesonets) have increased during the past several years, and methods to gather, quality control, and distribute these observations in real time have matured. These networks often provide data at higher spatial and temporal resolution than conventional observing systems (e.g., Automated Surface Observing Systems), and are routinely used by forecasters in real time to
that can be resolved at convection-allowing model resolutions. For example, the number of mesoscale surface observation networks (i.e., mesonets) have increased during the past several years, and methods to gather, quality control, and distribute these observations in real time have matured. These networks often provide data at higher spatial and temporal resolution than conventional observing systems (e.g., Automated Surface Observing Systems), and are routinely used by forecasters in real time to
the Advanced Research version (ARW) of the next-generation mesoscale Weather Research and Forecast Model (WRF) currently being developed and employed at the National Center for Atmospheric Research ( Skamarock et al. 2005 ). Two model domains coupled through two-way nesting are employed; the fine (coarse) domain has a horizontal grid spacing of 4.5 (13.5) km covering areas of 2700 × 2400 (8100 × 7200) km 2 . The model has 35 vertical levels with physics configurations that are the same as those
the Advanced Research version (ARW) of the next-generation mesoscale Weather Research and Forecast Model (WRF) currently being developed and employed at the National Center for Atmospheric Research ( Skamarock et al. 2005 ). Two model domains coupled through two-way nesting are employed; the fine (coarse) domain has a horizontal grid spacing of 4.5 (13.5) km covering areas of 2700 × 2400 (8100 × 7200) km 2 . The model has 35 vertical levels with physics configurations that are the same as those
complicated in complex terrain. Liu et al. (2008) conducted an interrange comparison of the model analyses and forecasts of five U.S. Army test and evaluation command ranges over a 5-yr period. They concluded that forecast errors vary from range to range and season to season. They also found that larger errors are typically associated with complex terrain. Zhong and Fast (2003) compared three mesoscale numerical models and evaluated the simulations over the Salt Lake Valley for cases influenced by
complicated in complex terrain. Liu et al. (2008) conducted an interrange comparison of the model analyses and forecasts of five U.S. Army test and evaluation command ranges over a 5-yr period. They concluded that forecast errors vary from range to range and season to season. They also found that larger errors are typically associated with complex terrain. Zhong and Fast (2003) compared three mesoscale numerical models and evaluated the simulations over the Salt Lake Valley for cases influenced by
. 2010 , 2013 ), the cases are still limited to ascertaining the effects of storm-induced sea surface cooling on TC intensity forecast skill in the vicinity of Japan. In this study, we conduct a large number of 3-day forecast experiments around Japan in order to obtain a reliable TC intensity forecast assessment. This is achieved by running a JMA nonhydrostatic atmospheric mesoscale model (AMSM) that is similar to an operational regional model and an atmosphere–ocean coupled mesoscale model (CMSM
. 2010 , 2013 ), the cases are still limited to ascertaining the effects of storm-induced sea surface cooling on TC intensity forecast skill in the vicinity of Japan. In this study, we conduct a large number of 3-day forecast experiments around Japan in order to obtain a reliable TC intensity forecast assessment. This is achieved by running a JMA nonhydrostatic atmospheric mesoscale model (AMSM) that is similar to an operational regional model and an atmosphere–ocean coupled mesoscale model (CMSM
events, and important questions remain. What is the relative importance of surface fluxes and downslope flow in thermal trough formation and evolution? Does advection play a significant role? Such issues will be addressed in this paper. Specifically, this manuscript will describe the synoptic and mesoscale evolution of a representative WCTT event that occurred on 13–16 May 2007 using observations and simulations from the Weather Research and Forecasting (WRF) Model. This event is similar to the
events, and important questions remain. What is the relative importance of surface fluxes and downslope flow in thermal trough formation and evolution? Does advection play a significant role? Such issues will be addressed in this paper. Specifically, this manuscript will describe the synoptic and mesoscale evolution of a representative WCTT event that occurred on 13–16 May 2007 using observations and simulations from the Weather Research and Forecasting (WRF) Model. This event is similar to the
