• Ackerman, S. A., , and J. A. Knox, 2007: Meteorology: Understanding the Atmosphere. 2nd ed. Thomson, 464 pp.

  • Aguado, E., , and J. E. Burt, 2007: Understanding Weather & Climate. 4th ed. Prentice Hall, 562 pp.

  • Bader, D. C., , and T. B. Mckee, 1983: Dynamical model simulation of the morning boundary layer development in deep mountain valleys. J. Climate Appl. Meteor., 22 , 341351.

    • Search Google Scholar
    • Export Citation
  • Banta, R. M., 1984: Daytime boundary layer evolution over mountainous terrain. Part I: Observations of the dry circulations. Mon. Wea. Rev., 112 , 340356.

    • Search Google Scholar
    • Export Citation
  • Banta, R. M., 1986: Daytime boundary layer evolution over mountainous terrain. Part II: Numerical studies of upslope flow duration. Mon. Wea. Rev., 114 , 11121130.

    • Search Google Scholar
    • Export Citation
  • Batchelor, G. K., 1967: An Introduction to Fluid Mechanics. Cambridge Press, 615 pp.

  • Braham, R. R., , and M. Draginis, 1960: Roots of orographic cumuli. J. Atmos. Sci., 17 , 214226.

  • Bright, D. R., , and S. L. Mullen, 2002: Short-range ensemble forecasts of precipitation during the Southwest monsoon. Wea. Forecasting, 17 , 10801100.

    • Search Google Scholar
    • Export Citation
  • Damiani, R., and Coauthors, 2008: Cumulus Photogrammetric, In-situ and Doppler Observations: The CuPIDO 2006 experiment. Bull. Amer. Meteor. Soc., 89 , 5773.

    • Search Google Scholar
    • Export Citation
  • de Wekker, S. F. J., , S. Zhong, , J. D. Fast, , and C. D. Whiteman, 1998: A numerical study of the thermally driven plain-to-basin wind over idealized basin topographies. J. Appl. Meteor., 37 , 606622.

    • Search Google Scholar
    • Export Citation
  • Fujita, T., , K. A. Styber, , and R. A. Brown, 1962: On the mesometeorological field studies near Flagstaff, Arizona. J. Appl. Meteor., 1 , 2642.

    • Search Google Scholar
    • Export Citation
  • Hernández, E., , J. de las Parras, , I. Martín, , A. Rúa, , and L. Gimeno, 1998: A field case study and numerical simulation of mountain flows with weak ambient winds. J. Appl. Meteor., 37 , 623637.

    • Search Google Scholar
    • Export Citation
  • Garrett, A. J., 1980: Orographic cloud over the eastern slopes of Mauna Loa Volcano, Hawaii, related to insolation and wind. Mon. Wea. Rev., 108 , 931941.

    • Search Google Scholar
    • Export Citation
  • Geerts, B., , Q. Miao, , and J. C. Demko, 2008: Pressure perturbations and upslope flow over a heated, isolated mountain. Mon. Wea. Rev., 136 , 42724288.

    • Search Google Scholar
    • Export Citation
  • Holton, J. R., 2004: An Introduction to Dynamic Meteorology. 4th ed. Elsevier/Academic Press, 535 pp.

  • Johnson, R. H., , and D. L. Priegnitz, 1981: Winter monsoon convection in the vicinity of north Borneo. Part II: Effects on large-scale fields. Mon. Wea. Rev., 109 , 16151628.

    • Search Google Scholar
    • Export Citation
  • Lenschow, D. H., , and B. B. Stankov, 1986: Length scales in the convective atmospheric boundary layer. J. Atmos. Sci., 43 , 11981209.

  • Lenschow, D. H., , P. B. Krummel, , and S. T. Siems, 1999: Measuring entrainment, divergence, and vorticity on the mesoscale from aircraft. J. Atmos. Oceanic Technol., 16 , 13841400.

    • Search Google Scholar
    • Export Citation
  • McNider, R. T., , and R. A. Pielke, 1981: Diurnal boundary-layer development over sloping terrain. J. Atmos. Sci., 38 , 21982212.

  • Raymond, D. J., , and M. H. Wilkening, 1980: Mountain-induced convection under fair weather conditions. J. Atmos. Sci., 37 , 26932706.

  • Raymond, D. J., , and M. H. Wilkening, 1982: Flow and mixing in New Mexico mountain cumuli. J. Atmos. Sci., 39 , 22112228.

  • Raymond, D. J., , and M. H. Wilkening, 1985: Characteristics of mountain-induced thunderstorms and cumulus congestus clouds from budget measurements. J. Atmos. Sci., 42 , 773783.

    • Search Google Scholar
    • Export Citation
  • Thyer, N. H., 1966: A theoretical explanation of mountain and valley winds by a numerical method. Meteor. Atmos. Phys., 15 , 318348.

  • Vergeiner, I., , and E. Dreiseitl, 1987: Valley winds and slope winds: Observations and elementary thoughts. Meteor. Atmos. Phys., 36 , 264268.

    • Search Google Scholar
    • Export Citation
  • Whiteman, C. D., 1990: Observations of thermally developed wind systems in mountainous terrain. Atmospheric Processes over Complex Terrain, Meteor. Monogr., No. 45, Amer. Meteor. Soc., 5–42.

    • Search Google Scholar
    • Export Citation
  • Whiteman, C. D., 2000: Mountain Meteorology: Fundamentals and Applications. Oxford University Press, 376 pp.

  • Wilson, J. W., , and W. E. Schreiber, 1986: Initiation of convective storms by radar-observed boundary-layer convergent lines. Mon. Wea. Rev., 114 , 25162536.

    • Search Google Scholar
    • Export Citation
  • Wilson, J. W., , G. B. Foote, , N. A. Crook, , J. C. Fankhauser, , C. G. Wade, , J. D. Tuttle, , and C. K. Mueller, 1992: The role of boundary layer convergence zones and horizontal rolls in the initiation of thunderstorms: A case study. Mon. Wea. Rev., 120 , 17851815.

    • Search Google Scholar
    • Export Citation
  • Yu, W., , Y. Liu, , T. Warner, , R. Bullock, , B. Brown, , and M. Ge, 2006: A comparison of very short-term QPFs for summer convection over complex terrain areas, with the NCAR/ATEC WRF and MM5-based RTFDDA systems. Seventh WRF Users Workshop, Boulder, CO, NCAR, 8.5. [Available online at http://www.mmm.ucar.edu/wrf/users/workshops/WS2006/abstracts/Session08/8_5_Yu.pdf].

  • Zehnder, J. A., , L. Zhang, , D. Hansford, , A. Radzan, , N. Selover, , and C. M. Brown, 2006: Using digital cloud photogrammetry to characterize the onset and transition from shallow to deep convection over orography. Mon. Wea. Rev., 134 , 25272546.

    • Search Google Scholar
    • Export Citation
  • Zehnder, J. A., , J. Hu, , and A. Razdan, 2007: A stereo photogrammetric technique applied to orographic convection. Mon. Wea. Rev., 135 , 22652277.

    • Search Google Scholar
    • Export Citation
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Boundary Layer Energy Transport and Cumulus Development over a Heated Mountain: An Observational Study

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  • 1 University of Wyoming, Laramie, Wyoming
  • | 2 Creighton University, Omaha, Nebraska
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Abstract

Aircraft and surface measurements of the boundary layer transport of mass and moisture toward an isolated, heated mountain are presented. The data were collected around the Santa Catalina Mountains in Arizona, 20–30 km in diameter, during the North American monsoon, on days with weak winds and cumulus congestus to cumulonimbus development over the mountain. Flights in the boundary layer around the mountain and surface station data indicate that mountain-scale anabatic surface wind generally develops shortly after sunrise, peaking at ∼1 m s−1 in strength close to solar noon. There is some evidence for a toroidal heat island circulation, with divergence in the upper boundary layer. The aircraft data and mainly the diurnal surface temperature and pressure patterns confirm that this circulation is driven by surface heating over the mountain. Three case studies suggest that growth spurts of orographic cumulus and cumulonimbus are not preceded by enhanced mountain-scale mass convergence near the surface, and that the decay of orographic deep convection is associated with divergence around the mountain.

Corresponding author address: Bart Geerts, Department of Atmospheric Sciences, University of Wyoming, Laramie, WY 82071. Email: geerts@uwyo.edu

Abstract

Aircraft and surface measurements of the boundary layer transport of mass and moisture toward an isolated, heated mountain are presented. The data were collected around the Santa Catalina Mountains in Arizona, 20–30 km in diameter, during the North American monsoon, on days with weak winds and cumulus congestus to cumulonimbus development over the mountain. Flights in the boundary layer around the mountain and surface station data indicate that mountain-scale anabatic surface wind generally develops shortly after sunrise, peaking at ∼1 m s−1 in strength close to solar noon. There is some evidence for a toroidal heat island circulation, with divergence in the upper boundary layer. The aircraft data and mainly the diurnal surface temperature and pressure patterns confirm that this circulation is driven by surface heating over the mountain. Three case studies suggest that growth spurts of orographic cumulus and cumulonimbus are not preceded by enhanced mountain-scale mass convergence near the surface, and that the decay of orographic deep convection is associated with divergence around the mountain.

Corresponding author address: Bart Geerts, Department of Atmospheric Sciences, University of Wyoming, Laramie, WY 82071. Email: geerts@uwyo.edu

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