Discrimination of Mesoscale Convective System Environments Using Sounding Observations

Weather and Forecasting - Tập 22 Số 5 - Trang 1045-1062 - 2007
Ariel Cohen1, Michael C. Coniglio2, Stephen F. Corfidi3, Sarah J. Corfidi3
1School of Meteorology, University of Oklahoma, Norman, Oklahoma*
2NOAA/National Severe Storms Laboratory, Norman, Oklahoma
3NOAA/NWS/NCEP Storm Prediction Center, Norman, Oklahoma

Tóm tắt

Abstract The prediction of the strength of mesoscale convective systems (MCSs) is a major concern to operational meteorologists and the public. To address this forecast problem, this study examines meteorological variables derived from sounding observations taken in the environment of quasi-linear MCSs. A set of 186 soundings that sampled the beginning and mature stages of the MCSs are categorized by their production of severe surface winds into weak, severe, and derecho-producing MCSs. Differences in the variables among these three MCS categories are identified and discussed. Mean low- to upper-level wind speeds and deep-layer vertical wind shear, especially the component perpendicular to the convective line, are excellent discriminators among all three categories. Low-level inflow relative to the system is found to be an excellent discriminator, largely because of the strong relationship of system severity to system speed. Examination of the mean wind and shear vectors relative to MCS motion suggests that cell propagation along the direction of cell advection is a trait that separates severe, long-lived MCSs from the slower-moving, nonsevere variety and that this is favored when both the deep-layer shear vector and the mean deep-layer wind are large and nearly parallel. Midlevel environmental lapse rates are found to be very good discriminators among all three MCS categories, while vertical differences in equivalent potential temperature and CAPE only discriminate well between weak and severe/derecho MCS environments. Knowledge of these variables and their distribution among the different categories of MCS intensity can be used to improve forecasts and convective watches for organized convective wind events.

Từ khóa


Tài liệu tham khảo

Anderson, 1998, Mesoscale convective complexes and persistent elongated convective systems over the United States during 1992 and 1993., Mon. Wea. Rev., 126, 578, 10.1175/1520-0493(1998)126<0578:MCCAPE>2.0.CO;2

Ashley, 2005, Derecho hazards in the United States., Bull. Amer. Meteor. Soc., 86, 1577, 10.1175/BAMS-86-11-1577

Atkins, 1991, Wet microburst activity over the southeastern United States: Implications for forecasting., Wea. Forecasting, 6, 470, 10.1175/1520-0434(1991)006<0470:WMAOTS>2.0.CO;2

Brooks, 1994, On the environments of tornadic and nontornadic mesocyclones., Wea. Forecasting, 9, 606, 10.1175/1520-0434(1994)009<0606:OTEOTA>2.0.CO;2

Bryan, G. H., and M. L.Weisman, 2006: The relative importance of lower-level and upper-level shear on the intensity of squall lines. Preprints, 23d Conf. on Severe Local Storms, St. Louis, MO, Amer. Meteor. Soc., CD-ROM, P4.5.

Burke, 2004, A 4-yr climatology of cold-season bow echoes over the continental United States., Wea. Forecasting, 19, 1061, 10.1175/811.1

Chappell, 1986, Quasi-stationary convective events., 10.1007/978-1-935704-20-1_13

Coniglio, 2004, Interpreting the climatology of derechos., Wea. Forecasting, 19, 595, 10.1175/1520-0434(2004)019<0595:ITCOD>2.0.CO;2

Coniglio, 2004, An observational study of derecho-producing convective systems., Wea. Forecasting, 19, 320, 10.1175/1520-0434(2004)019<0320:AOSODC>2.0.CO;2

Coniglio, 2006, Effects of upper-level shear on the structure and maintenance of strong, quasi-linear mesoscale convective systems., J. Atmos. Sci., 63, 1231, 10.1175/JAS3681.1

Coniglio, 2007, Forecasting the maintenance of quasi-linear mesoscale convective systems., Wea. Forecasting, 22, 556, 10.1175/WAF1006.1

Corfidi, 2003, Cold pools and MCS propagation: Forecasting the motion of downwind-developing MCSs., Wea. Forecasting, 18, 997, 10.1175/1520-0434(2003)018<0997:CPAMPF>2.0.CO;2

Corfidi, 1996, Predicting the movement of mesoscale convective complexes., Wea. Forecasting, 11, 41, 10.1175/1520-0434(1996)011<0041:PTMOMC>2.0.CO;2

Evans, 2001, Examination of derecho environments using proximity soundings., Wea. Forecasting, 16, 329, 10.1175/1520-0434(2001)016<0329:EODEUP>2.0.CO;2

Fovell, 1995, The temporal behavior of numerically simulated multicell-type storms. Part I: Modes of behavior., J. Atmos. Sci., 52, 2073, 10.1175/1520-0469(1995)052<2073:TTBONS>2.0.CO;2

Gale, 2002, Toward improved prediction of mesoscale convective system dissipation., Wea. Forecasting, 17, 856, 10.1175/1520-0434(2002)017<0856:TIPOMC>2.0.CO;2

Gilmore, 1998, The influence of midtropospheric dryness on supercell morphology and evolution., Mon. Wea. Rev., 126, 943, 10.1175/1520-0493(1998)126<0943:TIOMDO>2.0.CO;2

Hart, J. A., and P. R.Janish, cited. 2006: SeverePlot: Historical severe weather report database. Version 2.0. Storm Prediction Center, Norman, OK. [Available online at http://www.spc.noaa.gov/software/svrplot2/.].

Hilgendorf, 1998, A study of the evolution of mesoscale convective systems using WSR-88D data., Wea. Forecasting, 13, 437, 10.1175/1520-0434(1998)013<0437:ASOTEO>2.0.CO;2

Johns, 1993, Meteorological conditions associated with bow echo development in convective storms., Wea. Forecasting, 8, 294, 10.1175/1520-0434(1993)008<0294:MCAWBE>2.0.CO;2

Johns, 1987, Derechos: Widespread convectively induced windstorms., Wea. Forecasting, 2, 32, 10.1175/1520-0434(1987)002<0032:DWCIW>2.0.CO;2

Klimowski, 2003, Severe convective windstorms over the northern high plains of the United States., Wea. Forecasting, 18, 502, 10.1175/1520-0434(2003)18<502:SCWOTN>2.0.CO;2

Kuchera, 2006, Severe convective wind environments., Wea. Forecasting, 21, 595, 10.1175/WAF931.1

Laing, 2000, The large-scale environments of the global population of mesoscale convective complexes., Mon. Wea. Rev., 128, 2756, 10.1175/1520-0493(2000)128<2756:TLSEOT>2.0.CO;2

Maddox, 1983, Large-scale meteorological conditions associated with midlatitude, mesoscale convective complexes., Mon. Wea. Rev., 111, 1475, 10.1175/1520-0493(1983)111<1475:LSMCAW>2.0.CO;2

Maddox, 1986, Mesoscale convective complexes in the middle latitudes., 10.1007/978-1-935704-20-1_17

McCann, 1994, WINDEX: A new index for forecasting microburst potential., Wea. Forecasting, 9, 532, 10.1175/1520-0434(1994)009<0532:WNIFFM>2.0.CO;2

Merritt, J. H., and J. M.Fritsch, 1984: On the movement of the heavy precipitation areas of mid-latitude mesoscale convective complexes. Preprints, 10th Conf. on Weather Analysis and Forecasting, Clearwater, FL, Amer. Meteor. Soc., 529–536.

Miller, D. J., and R. H.Johns, 2000: A detailed look at extreme wind damage in derecho events. Preprints, 20th Conf. on Severe Local Storms, Orlando, FL, Amer. Meteor. Soc., 52–55.

Newton, 1958, Movement of large convective rainstorms in relation to winds aloft., Bull. Amer. Meteor. Soc., 39, 129, 10.1175/1520-0477-39.3.129

Parker, 2000, Organizational modes of midlatitude mesoscale convective systems., Mon. Wea. Rev., 128, 3413, 10.1175/1520-0493(2001)129<3413:OMOMMC>2.0.CO;2

Parker, 2004, Structures and dynamics of quasi-2D mesoscale convective systems., J. Atmos. Sci., 61, 545, 10.1175/1520-0469(2004)061<0545:SADOQM>2.0.CO;2

Proctor, 1989, Numerical simulations of an isolated microburst. Part II: Sensitivity experiments., J. Atmos. Sci., 46, 2143, 10.1175/1520-0469(1989)046<2143:NSOAIM>2.0.CO;2

Rotunno, 1988, A theory for strong, long-lived squall lines., J. Atmos. Sci., 45, 463, 10.1175/1520-0469(1988)045<0463:ATFSLL>2.0.CO;2

Schultz, 2000, The intricacies of instabilities., Mon. Wea. Rev., 128, 4143, 10.1175/1520-0493(2000)129<4143:TIOI>2.0.CO;2

Seitter, 1986, A numerical study of atmospheric density current motion including the effects of condensation., J. Atmos. Sci., 43, 3068, 10.1175/1520-0469(1986)043<3068:ANSOAD>2.0.CO;2

Stensrud, 2005, Comments on “‘A theory for strong long-lived squall lines’ revisited.”., J. Atmos. Sci., 62, 2989, 10.1175/JAS3514.1

Trapp, 2006, Buyer beware: Some words of caution on the use of severe wind reports in post-event assessment and research., Wea. Forecasting, 21, 408, 10.1175/WAF925.1

Trapp, 2003, Low-level mesovortices within squall lines and bow echoes. Part II: Their genesis and implications., Mon. Wea. Rev., 131, 2804, 10.1175/1520-0493(2003)131<2804:LMWSLA>2.0.CO;2

Wakimoto, 2001, Convectively driven high wind events., 10.1007/978-1-935704-06-5_7

Weisman, 1993, The genesis of severe, long-lived bow echoes., J. Atmos. Sci., 50, 645, 10.1175/1520-0469(1993)050<0645:TGOSLL>2.0.CO;2

Weisman, 2001, Bow echoes: A tribute to T. T. Fujita., Bull. Amer. Meteor. Soc., 82, 97, 10.1175/1520-0477(2001)082<0097:BEATTT>2.3.CO;2

Weisman, 2004, “A theory for long-lived squall lines” revisited., J. Atmos. Sci., 61, 361, 10.1175/1520-0469(2004)061<0361:ATFSLS>2.0.CO;2

Weisman, 1988, Structure and evolution of numerically simulated squall lines., J. Atmos. Sci., 45, 1990, 10.1175/1520-0469(1988)045<1990:SAEONS>2.0.CO;2

Weiss, S. J., J. A.Hart, and P. R.Janish, 2002: An examination of severe thunderstorm wind report climatology: 1970–1999. Preprints, 21st Conf. on Severe Local Storms, San Antonio, TX, Amer. Meteor. Soc., CD-ROM, 11B2.

Wheatley, 2006, Radar and damage analysis of severe bow echoes observed during BAMEX., Mon. Wea. Rev., 134, 791, 10.1175/MWR3100.1

Wilks, 1995, Statistical Methods in the Atmospheric Sciences.

Zipser, 1982, Use of a conceptual model of the life cycle of mesoscale convective systems to improve very-short-range forecasts.

Thông tin
Thông tin xuất bản

Weather and Forecasting

Tập 22 Số 5

1045-1062

Thông tin tác giả