• Anders, A. M., , G. H. Roe, , B. Hallet, , D. R. Montgomery, , N. Finnegan, , and J. Putkonen, 2006: Spatial patterns of precipitation and topography in the Himalaya. Tectonics, Climate and Landscape, Special Paper 398, S. Willet, N. Brandon, and D. Fiser, Eds., Geological Society of America, 39–53.

    • Search Google Scholar
    • Export Citation
  • Anders, A. M., , G. H. Roe, , D. R. Durran, , and J. M. Minder, 2007: Scale-scale spatial gradients in climatological precipitation on the Olympic peninsula. J. Hydrometeor., 8 , 10681081.

    • Search Google Scholar
    • Export Citation
  • Bao, J-W., , S. A. Michelson, , P. J. Neiman, , F. M. Ralph, , and J. M. Wilczak, 2006: Interpretation of enhanced integrated water-vapor bands associated with extratropical cyclones: Their formation and connection to tropical moisture. Mon. Wea. Rev., 134 , 10631080.

    • Search Google Scholar
    • Export Citation
  • Bevis, B. G., , S. Bussinger, , T. A. Herring, , C. Rocken, , R. A. Anthes, , and R. H. Ware, 1992: GPS meteorology: Remote sensing of atmospheric water vapor using the Global Positioning System. J. Geophys. Res., 97 , 1578715801.

    • Search Google Scholar
    • Export Citation
  • Bond, N. A., and Coauthors, 1997: The Coastal Observation and Simulation with Topography (COAST) experiment. Bull. Amer. Meteor. Soc., 78 , 19411955.

    • Search Google Scholar
    • Export Citation
  • Braun, S. A., 2006: High-Resolution simulation of Hurricane Bonnie (1998). Part II: Water budget. J. Atmos. Sci., 63 , 4364.

  • Braun, S. A., , R. Rotunno, , and J. B. Klemp, 1999a: Effects of coastal orography on landfalling cold fronts. Part I: Dry, inviscid dynamics. J. Atmos. Sci., 56 , 517533.

    • Search Google Scholar
    • Export Citation
  • Braun, S. A., , R. Rotunno, , and J. B. Klemp, 1999b: Effects of coastal orography on landfalling cold fronts. Part II: Effects of surface friction. J. Atmos. Sci., 56 , 33663384.

    • Search Google Scholar
    • Export Citation
  • Browning, K. A., 1990: Organization of clouds and precipitation in extratropical cyclones. Extratropical Cyclones: The Erik Palman Memorial Volume, C. W. Newton and E. Holopainen, Eds., Amer. Meteor. Soc., 129–153.

    • Search Google Scholar
    • Export Citation
  • Buzzi, A., , N. Tartaglione, , and P. Malguzzi, 1998: Numerical simulations of the 1994 Piedmont flood: Role of orography and moist processes. Mon. Wea. Rev., 126 , 23692383.

    • Search Google Scholar
    • Export Citation
  • Carlson, T. N., 1980: Airflow through midlatitude cyclones and the comma cloud pattern. Mon. Wea. Rev., 108 , 14981509.

  • Didlake Jr., A. C., 2007: An analysis of water vapor flux and orographic precipitation in Northern California. B.S. thesis, Dept. of Geology and Geophysics, Yale University, 47 pp.

  • Doswell, C. A., , C. Ramis, , R. Romero, , and S. Alonso, 1998: A diagnostic study of three heavy precipitation episodes in the western Mediterranean region. Wea. Forecasting, 13 , 102124.

    • Search Google Scholar
    • Export Citation
  • Ecklund, W. L., , D. A. Carter, , and B. B. Balsley, 1988: A UHF wind profiler for the boundary layer: Brief description and initial results. J. Atmos. Oceanic Technol., 5 , 432441.

    • Search Google Scholar
    • Export Citation
  • Galewsky, J., , and A. Sobel, 2005: Moist dynamics and orographic precipitation in northern and central California during the New Year’s Flood of 1997. Mon. Wea. Rev., 133 , 15941612.

    • Search Google Scholar
    • Export Citation
  • Grubišić, V., , R. K. Vellore, , and A. W. Huggins, 2005: Quantitative precipitation forecasting of wintertime storms in the Sierra Nevada: Sensitivity to microphysical parameterization and horizontal resolution. Mon. Wea. Rev., 133 , 28342859.

    • Search Google Scholar
    • Export Citation
  • Hahn, R. S., , and C. F. Mass, 2009: The impact of positive-definite moisture advection and low-level moisture flux bias over orography. Mon. Wea. Rev., 137 , 30553071.

    • Search Google Scholar
    • Export Citation
  • Heggli, M. F., , and R. M. Rauber, 1988: The characteristics and evolution of super-cooled water in winter time storms over the Sierra Nevada: A summary of microwave radiometric measurements taken during the Sierra Cooperative Pilot Project. J. Appl. Meteor., 27 , 9891015.

    • Search Google Scholar
    • Export Citation
  • Lackmann, G., , and J. Gyakum, 1999: Heavy cold-season precipitation in the northwestern United States: Synoptic climatology and an analysis of the flood of 17–18 January 1986. Wea. Forecasting, 14 , 687700.

    • Search Google Scholar
    • Export Citation
  • Lin, Y-L., , S. Chiao, , T-A. Wang, , M. L. Kaplan, , and R. Weglarz, 2001: Some common ingredients for heavy orographic precipitation. Wea. Forecasting, 16 , 633660.

    • Search Google Scholar
    • Export Citation
  • Marwitz, J. D., 1983: The kinematics of orographic airflow during Sierra storms. J. Atmos. Sci., 40 , 12181227.

  • Marwitz, J. D., 1986: A comparison of winter orographic storms over the San Juan Mountains and the Sierra Nevada. Precipitation Enhancement—A Scientific Challenge, Meteor. Monogr., No. 43, Amer. Meteor. Soc., 109–113.

    • Search Google Scholar
    • Export Citation
  • Marwitz, J. D., 1987: Deep orographic storms over the Sierra Nevada. Part I: Thermodynamic and kinematic structure. J. Atmos. Sci., 44 , 159185.

    • Search Google Scholar
    • Export Citation
  • Minder, J. R., , D. R. Durran, , G. H. Roe, , and A. M. Anders, 2008: The climatology of small-scale orographic precipitation over the Olympic Mountains: Patterns and processes. Quart. J. Roy. Meteor. Soc., 134 , 817839.

    • Search Google Scholar
    • Export Citation
  • Mesinger, F., and Coauthors, 2006: North American Regional Reanalysis. Bull. Amer. Meteor. Soc., 87 , 343360.

  • Neiman, P. J., , F. M. Ralph, , A. B. White, , D. E. Kingsmill, , and P. O. G. Persson, 2002: The statistical relationship between upslope flow and rainfall in California’s coastal mountains: Observations during CALJET. Mon. Wea. Rev., 130 , 14681492.

    • Search Google Scholar
    • Export Citation
  • Neiman, P. J., , B. E. Martner, , A. B. White, , G. A. Wick, , F. M. Ralph, , and D. E. Kingsmill, 2005: Wintertime nonbrightband rain in California and Oregon during CALJET and PACJET: Geographic, interannual, and synoptic variability. Mon. Wea. Rev., 133 , 11991223.

    • Search Google Scholar
    • Export Citation
  • Neiman, P. J., , F. M. Ralph, , A. B. White, , J. D. Lundquist, , and M. D. Dettinger, 2008: Meteorological characteristics and overland precipitation impacts of atmospheric rivers affecting the west coast of North America based on eight years of SSM/I satellite observations. J. Hydrometeor., 9 , 2247.

    • Search Google Scholar
    • Export Citation
  • Parish, T. R., 1982: Barrier winds along the Sierra Nevada Mountains. J. Appl. Meteor., 21 , 925930.

  • Pierrehumbert, R. T., , and B. Wyman, 1985: Upstream effects of mesoscale mountains. J. Atmos. Sci., 42 , 9771003.

  • Ralph, F. M., , P. J. Neiman, , and T. L. Keller, 1999: Deep-tropospheric gravity waves created by leeside cold fronts. J. Atmos. Sci., 56 , 29863009.

    • Search Google Scholar
    • Export Citation
  • Ralph, F. M., , P. J. Neiman, , and G. A. Wick, 2004: Satellite and CALJET aircraft observations of atmospheric rivers over the eastern North Pacific Ocean during the winter of 1997/98. Mon. Wea. Rev., 132 , 17211745.

    • Search Google Scholar
    • Export Citation
  • Ralph, F. M., , P. J. Neiman, , and R. Rotunno, 2005: Dropsonde observations in low-level jets over the northeastern Pacific Ocean from CALJET-1998 and PACJET-2001: Mean vertical profile and atmospheric river characteristics. Mon. Wea. Rev., 133 , 889910.

    • Search Google Scholar
    • Export Citation
  • Rauber, R. M., 1992: Microphysical structure and evolution of a Sierra Nevada shallow orographic cloud system. J. Appl. Meteor., 31 , 324.

    • Search Google Scholar
    • Export Citation
  • Reeves, H. D., , and Y. L. Lin, 2008: Dynamic forcing and mesoscale variability of heavy precipitation events over the Sierra Nevada Mountains. Mon. Wea. Rev., 136 , 6277.

    • Search Google Scholar
    • Export Citation
  • Reynolds, D. W., , and A. S. Dennis, 1986: A review of the Sierra Cooperative Pilot Project. Bull. Amer. Meteor. Soc., 67 , 513523.

  • Rotunno, R., , and R. Ferretti, 2001: Mechanisms of intense Alpine rainfall. J. Atmos. Sci., 58 , 17321749.

  • Skamarock, W. C., 2006: Positive-definite and montonic limiters for unrestricted-time step transport schemes. Mon. Wea. Rev., 134 , 22412250.

    • Search Google Scholar
    • Export Citation
  • Skamarock, W. C., , and J. B. Klemp, 2008: A time-split nonhydrostatic atmospheric model for research and NWP applications. J. Comput. Phys., 227 , 34653485.

    • Search Google Scholar
    • Export Citation
  • Skamarock, W. C., , and M. L. Weisman, 2009: The impact of positive-definite moisture transport on NWP precipitation forecasts. Mon. Wea. Rev., 137 , 488494.

    • Search Google Scholar
    • Export Citation
  • Skamarock, W. C., , J. B. Klemp, , J. Dudhia, , D. O. Gill, , D. M. Barker, , W. Wang, , and J. G. Powers, 2005: A description of the Advanced Research WRF version 2. NCAR Tech. Note, NCAR/TN-468+STR, 88 pp. [Available from UCAR Communications, P.O. Box 3000, Boulder, CO 80307].

    • Search Google Scholar
    • Export Citation
  • Smith, R. B., , and J. P. Evans, 2007: Orographic precipitation and water vapor fractionation over the southern Andes. J. Hydrometeor., 8 , 319.

    • Search Google Scholar
    • Export Citation
  • Smith, R. B., , Q. Jiang, , M. G. Fearon, , P. Tabary, , M. Dorninger, , J. D. Doyle, , and R. Beniot, 2003: Orographic precipitation and air mass transformation: An Alpine example. Quart. J. Roy. Meteor. Soc., 129 , 433454.

    • Search Google Scholar
    • Export Citation
  • Smith, R. B., , I. Barstard, , and L. Bonneau, 2005: Orographic precipitation and Oregon’s climate transition. J. Atmos. Sci., 62 , 177191.

    • Search Google Scholar
    • Export Citation
  • Smolarkiewicz, P. K., , and R. Rotunno, 1990: Low Froude number flow past three-dimensional obstacles. Part II: Upwind flow reversal zone. J. Atmos. Sci., 47 , 14981511.

    • Search Google Scholar
    • Export Citation
  • Strangeways, I. C., 1996: Back to basics: the ‘met. enclosure’: Part 2(b)—Raingauges, their errors. Weather, 51 , 298303.

  • Weber, B. L., , D. B. Wuertz, , D. C. Welsh, , and R. McPeek, 1993: Quality controls for profiler measurements of winds and RASS temperatures. J. Atmos. Oceanic Technol., 10 , 452464.

    • Search Google Scholar
    • Export Citation
  • Wentz, F. J., 1997: A well-calibrated ocean algorithm for SSM/I. J. Geophys. Res., 102 , 87038718.

  • White, A. B., , P. J. Neiman, , R. M. Ralph, , D. E. Kingsmill, , and P. O. G. Persson, 2003: Coastal orographic rainfall processes observed by radar during the California LandFalling Jets Experiment. J. Hydrometeor., 4 , 264282.

    • Search Google Scholar
    • Export Citation
  • Zhu, Y., , and R. E. Newell, 1998: A proposed algorithm for moisture fluxes from atmospheric rivers. Mon. Wea. Rev., 126 , 725735.

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Water Vapor Fluxes and Orographic Precipitation over Northern California Associated with a Landfalling Atmospheric River

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  • 1 Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina
  • | 2 NOAA/Earth System Research Laboratory, Boulder, Colorado
  • | 3 University of Colorado, CIRES, and NOAA/Earth System Research Laboratory, Boulder, Colorado
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Abstract

Atmospheric rivers accompanying Pacific storm systems play an important role in supplying moisture to the West Coast. Heavy precipitation associated with these systems falls not only along the west-facing slopes of the Coastal Range but also along the windward slopes of the interior Sierra Mountains. Simulations of the 29–31 December 2005 storm in northern California using the Weather Research and Forecasting (WRF) model were able to realistically resolve the structure and strength of the water vapor fluxes over ocean and land. The cross-barrier, southwesterly water vapor fluxes, peaking near 700 kg m−1 s−1 at the coast, dominated the airmass transformation over the northern California mountain complex. However, there was also significant northward water vapor flux along the base of the Sierras. The combination of a narrow, short-lived water vapor source from the atmospheric river, the gap in terrain facilitating flow around the coastal mountains, and the occurrence of a strong barrier jet at the base of the Sierras all contributed to the northward along-barrier water vapor fluxes within the storm. The coincident timing of the maximum water vapor flux into the central valley with the period when the barrier jet was well developed yielded up valley fluxes >300 kg m−1 s−1 for several hours. For the 29–31 December 2005 Pacific storm, the flow around the coastal terrain and up valley replenished about a quarter of the depleted water vapor lost over the coastal mountains.

* Current affiliation: National Weather Service, Raleigh, North Carolina.

Corresponding author address: Dr. Sandra E. Yuter, Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695. Email: seyuter@ncsu.edu

Abstract

Atmospheric rivers accompanying Pacific storm systems play an important role in supplying moisture to the West Coast. Heavy precipitation associated with these systems falls not only along the west-facing slopes of the Coastal Range but also along the windward slopes of the interior Sierra Mountains. Simulations of the 29–31 December 2005 storm in northern California using the Weather Research and Forecasting (WRF) model were able to realistically resolve the structure and strength of the water vapor fluxes over ocean and land. The cross-barrier, southwesterly water vapor fluxes, peaking near 700 kg m−1 s−1 at the coast, dominated the airmass transformation over the northern California mountain complex. However, there was also significant northward water vapor flux along the base of the Sierras. The combination of a narrow, short-lived water vapor source from the atmospheric river, the gap in terrain facilitating flow around the coastal mountains, and the occurrence of a strong barrier jet at the base of the Sierras all contributed to the northward along-barrier water vapor fluxes within the storm. The coincident timing of the maximum water vapor flux into the central valley with the period when the barrier jet was well developed yielded up valley fluxes >300 kg m−1 s−1 for several hours. For the 29–31 December 2005 Pacific storm, the flow around the coastal terrain and up valley replenished about a quarter of the depleted water vapor lost over the coastal mountains.

* Current affiliation: National Weather Service, Raleigh, North Carolina.

Corresponding author address: Dr. Sandra E. Yuter, Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695. Email: seyuter@ncsu.edu

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