Mesoscale Gravity Waves and Their Environment in the Central United States during STORM-FEST

Steven E. Koch Department of Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina

Search for other papers by Steven E. Koch in
Current site
Google Scholar
PubMed
Close
and
Leanne M. Siedlarz Department of Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina

Search for other papers by Leanne M. Siedlarz in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

In an effort to better understand mesoscale gravity waves in winter storms in the central United States—their frequency of occurrence, wave characteristics, the general conditions under which they occur, and their effects upon the weather—mesoscale surface and rawinsonde data as well as radar and satellite imagery collected during the Storm-scale Operational and Research Meteorology–Fronts and Experimental System Test are analyzed. In addition, factors affecting the ability of objective surface map analysis to properly represent the waves are investigated.

Thirteen coherent pressure pulse events with amplitudes of 0.2–4.0 mb and periods of 1–6 h were identified in the surface pressure data during the 6 weeks of the project, involving 34% of the total hours investigated. A variety of wave types occurred, including wavelets, wave trains, and singular waves. The three largest amplitude events were analyzed in detail using autospectral analysis and a Barnes time-to-space conversion objective analysis of bandpass-filtered mesonet data. All three events displayed high perturbation pressure–wind covariances (pu*′), consistent with a gravity wave explanation for the disturbances (u* is the wind component in the direction of wave propagation). The pu*′ values were closely related to the strength of the wave amplitudes. The waves found in these events displayed mean phase velocities of 19.9–27.9 m s−1, wavelengths of 200–260 km, and periods of 2.3–3.5 h.

Wave crests appeared to be closely aligned with associated rainbands throughout their lifetimes, suggesting that a codependency existed. Some of the waves were evident before the rainbands formed, indicating that the precipitation developed in response to the waves, though this was not true for all of the waves. Values of pu*′ decreased during the development stage of deep convection, but high covariance between the pressure and wind fields redeveloped as the thunderstorms and incipient gravity wave matured into a stable, coupled mesoscale convective system.

Three of the four wave events displaying the largest amplitudes occurred primarily on the cool side of a stationary front in an environment in which a jet streak was approaching an inflection axis in a diffluent height field downstream from an upper-level trough. The waves also extended some distance into the warm sector in the presence of a statically stable lower troposphere, suggesting wave ducting was operative. The results indicate that this conceptual model for the wave environment should prove useful as a tool for forecasting the most significant mesoscale gravity wave events.

Corresponding author address: Dr. Steven E. Koch, Department of Marine, Earth and Atmospheric Sciences, North Carolina State University, Campus Box 8208, Raleigh, NC 27695-8208.

Email: Steve_Koch@ncsu.edu

Abstract

In an effort to better understand mesoscale gravity waves in winter storms in the central United States—their frequency of occurrence, wave characteristics, the general conditions under which they occur, and their effects upon the weather—mesoscale surface and rawinsonde data as well as radar and satellite imagery collected during the Storm-scale Operational and Research Meteorology–Fronts and Experimental System Test are analyzed. In addition, factors affecting the ability of objective surface map analysis to properly represent the waves are investigated.

Thirteen coherent pressure pulse events with amplitudes of 0.2–4.0 mb and periods of 1–6 h were identified in the surface pressure data during the 6 weeks of the project, involving 34% of the total hours investigated. A variety of wave types occurred, including wavelets, wave trains, and singular waves. The three largest amplitude events were analyzed in detail using autospectral analysis and a Barnes time-to-space conversion objective analysis of bandpass-filtered mesonet data. All three events displayed high perturbation pressure–wind covariances (pu*′), consistent with a gravity wave explanation for the disturbances (u* is the wind component in the direction of wave propagation). The pu*′ values were closely related to the strength of the wave amplitudes. The waves found in these events displayed mean phase velocities of 19.9–27.9 m s−1, wavelengths of 200–260 km, and periods of 2.3–3.5 h.

Wave crests appeared to be closely aligned with associated rainbands throughout their lifetimes, suggesting that a codependency existed. Some of the waves were evident before the rainbands formed, indicating that the precipitation developed in response to the waves, though this was not true for all of the waves. Values of pu*′ decreased during the development stage of deep convection, but high covariance between the pressure and wind fields redeveloped as the thunderstorms and incipient gravity wave matured into a stable, coupled mesoscale convective system.

Three of the four wave events displaying the largest amplitudes occurred primarily on the cool side of a stationary front in an environment in which a jet streak was approaching an inflection axis in a diffluent height field downstream from an upper-level trough. The waves also extended some distance into the warm sector in the presence of a statically stable lower troposphere, suggesting wave ducting was operative. The results indicate that this conceptual model for the wave environment should prove useful as a tool for forecasting the most significant mesoscale gravity wave events.

Corresponding author address: Dr. Steven E. Koch, Department of Marine, Earth and Atmospheric Sciences, North Carolina State University, Campus Box 8208, Raleigh, NC 27695-8208.

Email: Steve_Koch@ncsu.edu

Save
  • Adams, M., 1996: Terrain induced mid-tropospheric frontogenesis and jet streak development during STORM-FEST IOP 17, 8 and 9 March 1992. Ph.D. dissertation, North Carolina State University, 214 pp. [Available from North Carolina State University, Dept. of Marine, Earth, and Atmospheric Sciences, Campus Box 8208, Raleigh, NC 27695-8208.].

  • Barnes, S. L., F. Caracena, and A. Marroquin, 1996: Extracting synoptic-scale diagnostic information from mesoscale models: The Eta Model, gravity waves, and quasigeostrophic diagnostics. Bull. Amer. Meteor. Soc.,77, 519–528.

  • Bosart, L. F., and J. P. Cussen Jr., 1973: Gravity wave phenomena accompanying East Coast cyclogenesis. Mon. Wea. Rev.,101, 446–454.

  • ——, and F. Sanders, 1986: Mesoscale structure in the megalopolitan snowstorm of 11–12 February 1983. Part III: A large-amplitude gravity wave. J. Atmos. Sci.,43, 924–939.

  • ——, and A. Seimon, 1988: A case study of an unusually intense atmospheric gravity wave. Mon. Wea. Rev.,116, 1857–1886.

  • Corbet, J., C. Mueller, C. Burghart, K. Gould, and G. Granger, 1994:Zeb: Software for integration, display, and management of diverse environmental datasets. Bull. Amer. Meteor. Soc.,75, 783–792.

  • Duchon, C. E., 1979: Lanczos filtering in one and two dimensions. J. Appl. Meteor.,18, 1016–1022.

  • Einaudi, F., A. J. Bedard, and J. J. Finnigan, 1989: A climatology of gravity waves and other coherent disturbances at the Boulder Atmospheric Observatory during March–April 1984. J. Atmos. Sci.,46, 303–329.

  • Eom, J. K., 1975: Analysis of the internal gravity wave occurrence of 19 April 1970 in the Midwest. Mon. Wea. Rev.,103, 217–226.

  • Friday, E. W., Jr., 1993: Associated restructuring of the National Weather Service: An overview. Bull. Amer. Meteor. Soc.,75, 43–48.

  • Fujita, T. T., 1955: Results of detailed synoptic studies of squall lines. Tellus,7, 405–436.

  • Gossard, E. E. and W. B. Sweezy, 1974: Dispersion and spectra of gravity waves in the atmosphere. J. Atmos. Sci.,31, 1540–1548.

  • ——, and W. H. Hooke, 1975: Waves in the Atmosphere. Elsevier, New York, 456 pp.

  • Grivet-Talocia, S., F. Einaudi, W. L. Clark, R. D. Dennett, G. D. Nastrom, and T. E. VanZandt, 1999: A 4-yr climatology of pressure disturbances using a barometer network in central Illinois. Mon. Wea. Rev.,127, 1613–1629.

  • Hauf, T., U. Finke, J. Neisser, G. Bull, and J.-G. Stagenberg, 1996: A ground-based network for atmospheric pressure fluctuations. J. Atmos. Oceanic Technol.,13, 1001–1023.

  • Hobbs, P. V., J. D. Locatelli, and J. E. Martin, 1990: Cold fronts aloft and the forecasting of precipitation and severe weather east of the Rocky Mountains. Wea. Forecasting,5, 613–626.

  • ——, ——, and ——, 1996: A new conceptual model for cyclones generated in the lee of the Rocky Mountains. Bull. Amer. Meteor. Soc.,77, 1169–1178.

  • Jin, Y., 1997: A numerical model study of the role of mesoscale gravity waves in rainband dynamics in the central United States during STORM-FEST. Ph. D. dissertation, North Carolina State University, 318 pp. [Available from North Carolina State University, Dept. of Marine, Earth, and Atmospheric Sciences, Campus Box 8208, Raleigh, NC 27695-8208.].

  • Johnson, R. H., and P. J. Hamilton, 1988: The relationship of surface pressure features to the precipitation and airflow structure of an intense midlatitude squall line. Mon. Wea. Rev.,116, 1444–1472.

  • Kaplan, M. L., S. E. Koch, Y.-L. Lin, and R. Weglarz, 1997: Numerical simulations of a gravity wave event over CCOPE. Part I: The role of geostrophic adjustment in mesoscale jetlet formation. Mon. Wea. Rev.,125, 1185–1211.

  • Keyser, D., B. D. Schmidt, and D. G. Duffy, 1989: A technique for representing three-dimensional vertical circulations in baroclinic disturbances. Mon. Wea. Rev.,117, 2463–2494.

  • Koch, S. E., and P. B. Dorian, 1988: A mesoscale gravity wave event observed during CCOPE. Part III: Wave environment and probable source mechanisms. Mon. Wea. Rev.,116, 2570–2592.

  • ——, and R. E. Golus, 1988: A mesoscale gravity wave event observed during CCOPE. Part I: Multi-scale statistical analysis of wave characteristics. Mon. Wea. Rev.,116, 2527–2544.

  • ——, and C. O’Handley, 1997: Operational forecasting and detection of mesoscale gravity waves. Wea. Forecasting,12, 253–281.

  • ——, M. desJardins, and P. Kocin, 1983: An interactive Barnes objective map analysis scheme for use with satellite and conventional data. J. Climate Appl. Meteor.,22, 1487–1503.

  • ——, R. E. Golus, and P. B. Dorian, 1988: A mesoscale gravity wave event observed during CCOPE. Part II: Interactions between mesoscale convective systems and the antecedent waves. Mon. Wea. Rev.,116, 2545–2569.

  • ——, D. Hamilton, D. Kramer, and A. Langmaid, 1998: Mesoscale dynamics in the Palm Sunday tornado outbreak. Mon. Wea. Rev.,126, 2031–2060.

  • Lin, Y.-L., 1994: Airflow over mesoscale heat sources. Part II: Responses in a shear flow. Proc. Natl. Sci. Council ROC (A),18, 119–150.

  • ——, and R. C. Goff, 1988: A study of a mesoscale solitary wave in the atmosphere originating near a region of deep convection. J. Atmos. Sci.,45, 194–205.

  • Lindzen, R. S., and K. K. Tung, 1976: Banded convective activity and ducted gravity waves. Mon. Wea. Rev.,104, 1602–1617.

  • Locatelli, J. D., J. E. Martin, J. A. Castle, and P. V. Hobbs, 1995: Structure and evolution of winter cyclones in the central United States and their effects on the distribution of precipitation. Part III: The development of a squall line associated with weak cold frontogenesis aloft. Mon. Wea. Rev.,123, 2641–2662.

  • ——, M. T. Stoelinga, R. D. Schwartz, and P. V. Hobbs, 1997: Surface convergence induced by cold fronts aloft and prefrontal surges. Mon. Wea. Rev.,125, 2808–2820.

  • Loughe, A. F., C.-C. Lai, and D. Keyser, 1995: A technique for diagnosing three-dimensional ageostrophic circulations in baroclinic disturbances on limited-area domains. Mon. Wea. Rev.,123, 1276–1303.

  • Martin, J. E., J. D. Locatelli, P. V. Hobbs, P.-Y. Wang, and J. A. Castle, 1995: Structure and evolution of winter cyclones in the central United States and their effects on the distribution of precipitation. Part I: A synoptic-scale rainband associated with a dryline and lee trough. Mon. Wea. Rev.,123, 241–264.

  • Pecnick, M. J., and, J. A. Young, 1984: Mechanics of a strong subsynoptic gravity wave deduced from satellite and surface observations. J. Atmos. Sci.,41, 1850–1862.

  • Pokrandt, P. J., G. J. Tripoli, and D. D. Houghton, 1997: Processes leading to the formation of mesoscale waves in the midwest cyclone of 15 December 1987. Mon. Wea. Rev.,124, 2726–2752.

  • Powers, J. G., 1997: Numerical model simulation of a mesoscale gravity-wave event: Sensitivity tests and spectral analyses. Mon. Wea. Rev.,125, 1838–1869.

  • ——, and R. J. Reed, 1993: Numerical simulation of the large-amplitude mesoscale gravity-wave event of 15 December 1987 in the central United States. Mon. Wea. Rev.,121, 2285–2306.

  • Ralph, F. M., M. Crochet, and S. V. Venkateswaran, 1993: Observations of a mesoscale ducted gravity wave. J. Atmos. Sci.,50, 3277–3291.

  • Ramamurthy, M. K., R. M. Rauber, B. P. Collins, and N. K. Malhotra, 1993: A comparative study of large-amplitude gravity wave events. Mon. Wea. Rev.,121, 2951–2974.

  • Raymond, D. J., 1983: Wave-CISK in mass form. J. Atmos. Sci.,40, 2561–2571.

  • Rottman, J. W., and F. Einaudi, 1993: Solitary waves in the atmosphere. J. Atmos. Sci.,50, 2116–2136.

  • Schneider, R. S., 1990: Large-amplitude mesoscale wave disturbances within the intense Midwest extratropical cyclone of 15 December 1987. Wea. Forecasting,5, 533–557.

  • Siedlarz, L. M., 1996: A climatology of mesoscale wave disturbances seen in mesonet data during STORM-FEST. M.S. thesis, North Carolina State University, 200 pp. [Available from North Carolina State University, Dept. of Marine, Earth, and Atmospheric Sciences, Campus Box 8208, Raleigh, NC 27695-8208.].

  • Stobie, J. G., F. Einaudi, and L. W. Uccellini, 1983: A case study of gravity waves–convective interactions: 9 May 1979. J. Atmos. Sci.,40, 2804–2830.

  • Szoke, E., J., J. M. Brown, J. A. McGinley, and D. Rodgers, 1994: Forecasting for a large field program: STORM-FEST. Wea. Forecasting,9, 593–605.

  • Tepper, M., 1951: On the desiccation of a cloud bank by a propagating pressure wave. Mon. Wea. Rev.,79, 61–70.

  • Trexler, C. M., Y. Jin, and S. E. Koch, 1998: Vertical structure of a mesoscale gravity wave event detected during STORM-FEST. Preprints, 16th Conf. on Weather Analysis and Forecasting, Phoenix, AZ, Amer. Meteor. Soc., 463–465.

  • Uccellini, L. W., 1975: A case study of apparent gravity wave initiation of severe convective storms. Mon. Wea. Rev.,103, 497–513.

  • ——, and S. E. Koch, 1987: The synoptic setting and possible energy sources for mesoscale wave disturbances. Mon. Wea. Rev.,115, 721–729.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 490 84 3
PDF Downloads 246 55 3