Editorial Type:
Article
Article Type:
Research Article

Misocyclone Characteristics along Florida Gust Fronts during CaPE

Katja Friedrich NOAA–CIRES/Environmental Technology Laboratory, University of Colorado, Boulder, Colorado

Search for other papers by Katja Friedrich in
Current site
Google Scholar
PubMed Close
,
David E. Kingsmill NOAA–CIRES/Environmental Technology Laboratory, University of Colorado, Boulder, Colorado

Search for other papers by David E. Kingsmill in
Current site
Google Scholar
PubMed Close
, and
Carl R. Young Desert Research Institute, Reno, Nevada

Search for other papers by Carl R. Young in
Current site
Google Scholar
PubMed Close
Print Publication:
01 Nov 2005
DOI:
https://doi.org/10.1175/MWR3040.1
Page(s):
3345–3367
Restricted access

Abstract

Multiple-Doppler radar and rawinsonde data are used to examine misocyclone characteristics along gust fronts observed during the Convection and Precipitation/Electrification (CaPE) project in Florida. The objective of this study is to investigate the observational representativeness of previous numerical simulations of misocyclones by employing a consistent analysis strategy to 11 gust fronts observed in the same region. The investigation focuses on the intensity range of misocyclones and their organization along gust fronts; the relationship between misocyclone intensity and horizontal wind shear, vertical wind shear, and static stability; and the relationship between misocyclones and convection initiation.

The intensity of misocyclones, as indicated by the maximum values of vertical vorticity, varied from 2.8 × 10−3 to 13.9 × 10−3 s−1, although all but one case exhibited values less than 6.4 × 10−3 s−1. Organized misocyclone patterns were only found along small segments of gust fronts. Within those segments misocyclones were spaced between 3 and 7 km. Results show that the intensity of misocyclones was most closely related to the strength of horizontal wind shear across the gust front. The relationship between misocyclone intensity and vertical wind shear and static stability was not as clear. Although convection was initiated along the gust front in 7 of the 11 cases, those regions were not collocated with or in close proximity to misocyclones.

Corresponding author address: David Kingsmill, CIRES, 216 UCB, Boulder, CO 80309-0216. Email: David.Kingsmill@colorado.edu

Abstract

Multiple-Doppler radar and rawinsonde data are used to examine misocyclone characteristics along gust fronts observed during the Convection and Precipitation/Electrification (CaPE) project in Florida. The objective of this study is to investigate the observational representativeness of previous numerical simulations of misocyclones by employing a consistent analysis strategy to 11 gust fronts observed in the same region. The investigation focuses on the intensity range of misocyclones and their organization along gust fronts; the relationship between misocyclone intensity and horizontal wind shear, vertical wind shear, and static stability; and the relationship between misocyclones and convection initiation.

The intensity of misocyclones, as indicated by the maximum values of vertical vorticity, varied from 2.8 × 10−3 to 13.9 × 10−3 s−1, although all but one case exhibited values less than 6.4 × 10−3 s−1. Organized misocyclone patterns were only found along small segments of gust fronts. Within those segments misocyclones were spaced between 3 and 7 km. Results show that the intensity of misocyclones was most closely related to the strength of horizontal wind shear across the gust front. The relationship between misocyclone intensity and vertical wind shear and static stability was not as clear. Although convection was initiated along the gust front in 7 of the 11 cases, those regions were not collocated with or in close proximity to misocyclones.

Corresponding author address: David Kingsmill, CIRES, 216 UCB, Boulder, CO 80309-0216. Email: David.Kingsmill@colorado.edu

Save
Cover Monthly Weather Review
Monthly Weather Review

  • Arnott, N. R., and Y. P. Richardson, 2004: High resolution observations of a cold front on 10 June 2002. Preprints, 22d Conf. on Severe Local Storms, Hyannis, MA, Amer. Meteor. Soc., CD-ROM, 16A.3.

  • Arnott, N. R., Y. P. Richardson, J. M. Wurman, and E. M. Rasmussen, 2005: Relationship between a weakening cold front, misocyclones, and cloud development on 10 June 2002 during IHOP. Mon. Wea. Rev., in press.

    • Search Google Scholar
    • Export Citation

  • Atkins, N. T., and R. M. Wakimoto, 1997: Influence of the synoptic-scale flow on sea breezes observed during CaPE. Mon. Wea. Rev., 125 , 2112–2130.

    • Search Google Scholar
    • Export Citation

  • Atkins, N. T., R. M. Wakimoto, and T. M. Weckwerth, 1995: Observations of the sea-breeze front during CaPE. Part II: Dual-Doppler and aircraft analysis. Mon. Wea. Rev., 123 , 944–969.

    • Search Google Scholar
    • Export Citation

  • Atkins, N. T., R. M. Wakimoto, and C. L. Ziegler, 1998: Observations of the finescale structure of a dryline during VORTEX 95. Mon. Wea. Rev., 126 , 525–550.

    • Search Google Scholar
    • Export Citation

  • Carbone, R. E., 1982: A severe frontal rainband. Part I: Stormwide hydrodynamic structure. J. Atmos. Sci., 39 , 258–279.

  • Carbone, R. E., 1983: A severe frontal rainband. Part II: Tornado parent vortex circulation. J. Atmos. Sci., 40 , 2639–2654.

  • Carbone, R. E., M. J. Carpenter, and C. D. Burghart, 1985: Doppler radar sampling limitations in convective storms. J. Atmos. Oceanic Technol., 2 , 357–361.

    • Search Google Scholar
    • Export Citation

  • Carbone, R. E., J. W. Conway, N. A. Crook, and M. W. Moncrieff, 1990: The generation and propagation of nocturnal squall line. Part I: Observations and implications for mesoscale predictability. Mon. Wea. Rev., 118 , 26–49.

    • Search Google Scholar
    • Export Citation

  • Cressman, G. P., 1959: An operational objective analysis system. Mon. Wea. Rev., 87 , 367–374.

  • Droegemeier, K. K., 1985: The Numerical Simulation of Thunderstorm Outflow Dynamics. Ph.D. dissertation, University of Illinois at Urbana–Champagne, 695 pp.

  • Frankhauser, J. C., N. A. Crook, J. Tuttle, L. J. Miller, and C. G. Wade, 1995: Initiation of deep convection along boundary layer convergence lines in a semitropical environment. Mon. Wea. Rev., 123 , 291–313.

    • Search Google Scholar
    • Export Citation

  • Fujita, T. T., 1981: Tornadoes and downbursts in the context of generalized planetary scales. J. Atmos. Sci., 38 , 1511–1534.

  • Kingsmill, D. E., 1995: Convection initiation associated with a sea-breeze front, a gust front, and their collision. Mon. Wea. Rev., 123 , 2913–2933.

    • Search Google Scholar
    • Export Citation

  • Kingsmill, D. E., and N. A. Crook, 2003: An observational study of atmospheric bore formation from colliding density currents. Mon. Wea. Rev., 131 , 2985–3002.

    • Search Google Scholar
    • Export Citation

  • Laird, N. F., D. A. R. Kristovich, R. M. Rauber, H. T. Ochs, and L. J. Miller, 1995: The Cape Canaveral sea and river breezes: Kinematic structure and convective initiation. Mon. Wea. Rev., 123 , 2942–2956.

    • Search Google Scholar
    • Export Citation

  • Lee, B. D., and R. B. Wilhelmson, 1997a: The numerical simulation of non-supercell tornadogenesis. Part I: Initiation and evolution of pretornadic misocyclone circulation along a dry outflow boundary. J. Atmos. Sci., 54 , 32–60.

    • Search Google Scholar
    • Export Citation

  • Lee, B. D., and R. B. Wilhelmson, 1997b: The numerical simulation of non-supercell tornadogenesis. Part II: Evolution of a family of tornadoes along a weak outflow boundary. J. Atmos. Sci., 54 , 2387–2415.

    • Search Google Scholar
    • Export Citation

  • Marquis, J. N., and Y. P. Richardson, 2004: Observations of misocyclones along boundaries during IHOP. Preprints, 22d Conf. on Severe Local Storms, Hyannis, MA, Amer. Meteor. Soc., CD-ROM, 16A.5.

  • Mueller, C. K., and R. E. Carbone, 1987: Dynamics of a thunderstorm outflow. J. Atmos. Sci., 44 , 1879–1898.

  • Mueller, C. K., J. W. Wilson, and N. A. Crook, 1993: The utility of sounding and mesonet data to nowcast thunderstorm initiation. Wea. Forecasting, 8 , 132–146.

    • Search Google Scholar
    • Export Citation

  • Murphey, H. V., R. M. Wakimoto, C. Flamant, and D. E. Kingsmill, 2005: Dryline on 19 June 2002 during IHOP. Part I: Airborne Doppler and LEANDRE II analyses of the thin line structure and convection initiation. Mon. Wea. Rev., in press.

    • Search Google Scholar
    • Export Citation

  • Neumann, J., 1951: Land breezes and nocturnal thunderstorms. J. Meteor., 8 , 60–67.

  • Pielke, R. A., 1974: A three-dimensional numerical model of the sea-breezes over south Florida. Mon. Wea. Rev., 102 , 115–139.

  • Purdom, J. F. W., 1976: Some uses of high-resolution GOES imagery in the mesoscale forecasting of convection and its behavior. Mon. Wea. Rev., 104 , 1474–1483.

    • Search Google Scholar
    • Export Citation

  • Purdom, J. F. W., 1982: Subjective interpretation of geostationary satellite data for nowcasting. Nowcasting, K. Browning, Ed., Academic Press, 149–166.

    • Search Google Scholar
    • Export Citation

  • Rotunno, R., J. B. Klemp, and M. L. Weisman, 1988: A theory for strong, long-lived squall lines. J. Atmos. Sci., 45 , 463–485.

  • Wakimoto, R. M., and J. W. Wilson, 1989: Non-supercell tornadoes. Mon. Wea. Rev., 117 , 1113–1140.

  • Wakimoto, R. M., and J. K. Lew, 1993: Observation of a Florida waterspout during CaPE. Wea. Forecasting, 8 , 412–423.

  • Wakimoto, R. M., and N. T. Atkins, 1994: Observations of the sea-breeze front during CaPE. Part I: Single-Doppler, satellite, and cloud photogrammetric analysis. Mon. Wea. Rev., 122 , 1092–1114.

    • Search Google Scholar
    • Export Citation

  • Wakimoto, R. M., and D. E. Kingsmill, 1995: Structure of an atmospheric undular bore generated from colliding boundaries during CaPE. Mon. Wea. Rev., 123 , 1374–1393.

    • Search Google Scholar
    • Export Citation

  • Weckwerth, T. M., 2000: The effect of small-scale moisture variability on thunderstorm initiation. Mon. Wea. Rev., 128 , 4017–4030.

  • Weckwerth, T. M., and R. M. Wakimoto, 1992: The initiation and organization of convective cells atop a cold-air outflow boundary. Mon. Wea. Rev., 120 , 2169–2187.

    • Search Google Scholar
    • Export Citation

  • Weckwerth, T. M., J. W. Wilson, and R. M. Wakimoto, 1996: Thermodynamic and variability within the boundary layer due to horizontal convective rolls. Mon. Wea. Rev., 124 , 769–784.

    • Search Google Scholar
    • Export Citation

  • Wilson, J. W., and W. E. Schreiber, 1986: Initiation of convective storms at radar-observed boundary-layer convergence lines. Mon. Wea. Rev., 114 , 2516–2536.

    • Search Google Scholar
    • Export Citation

  • Wilson, J. W., and D. L. Megenhardt, 1997: Thunderstorm initiation, organization, and lifetime associated with Florida boundary layer convergence lines. Mon. Wea. Rev., 125 , 1507–1525.

    • Search Google Scholar
    • Export Citation

  • Wilson, J. W., G. B. Foote, N. A. Crook, J. C. Frankhauser, C. G. Wade, J. D. Tuttle, C. K. Mueller, and S. K. Krueger, 1992: The role of the boundary-layer convergence zones and horizontal rolls in the initiation of thunderstorms: A case study. Mon. Wea. Rev., 120 , 1785–1815.

    • Search Google Scholar
    • Export Citation

  • Yuter, S. E., and R. A. Houze, 1995: Three-dimensional kinematic and microphysical evolution of Florida cumulonimbus. Part I: Spatial distribution of updraft, downdraft, and precipitation. Mon. Wea. Rev., 123 , 1921–1940.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 1298 1035 62
PDF Downloads 181 35 2