TITLE

A Review of Cold Fronts with Prefrontal Troughs and Wind Shifts

AUTHOR(S)
Schultz, David M.
PUB. DATE
August 2005
SOURCE
Monthly Weather Review;Aug2005, Vol. 133 Issue 8, p2449
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The conceptual model of a classical surface-based cold front consists of a sharp temperature decrease coincident with a pressure trough and a distinct wind shift at the surface. Many cold fronts, however, do not conform to this model—time series at a single surface station may possess a pressure trough and wind shift in the warm air preceding the cold front (hereafter called a prefrontal trough and prefrontal wind shift, respectively). Although many authors have recognized these prefrontal features previously, a review of the responsible mechanisms has not been performed to date. This paper presents such a review. Ten disparate mechanisms with different frontal structures have been identified from the previous literature. These mechanisms include those external to the front (i.e., those not directly associated with the cold front itself): synoptic-scale forcing, interaction with lee troughs/drylines, interaction with fronts in the mid- and upper troposphere, and frontogenesis associated with inhomogeneities in the prefrontal air. Mechanisms internal to the front (i.e., those directly associated with the structure and dynamics of the front) include the following: surface friction, frontogenesis acting on alongfront temperature gradients, moist processes, descent of air, ascent of air at the front, and generation of prefrontal bores/gravity waves. Given the gaps in our knowledge of the structure, evolution, and dynamics of surface cold fronts, this paper closes with an admonition for improving the links between theory, observations, and modeling to advance understanding and develop better conceptual models of cold fronts, with the goal of improving both scientific understanding and operational forecasting.
ACCESSION #
17996973

 

Related Articles

  • NOGAPS-ALPHA Simulations of the 2002 Southern Hemisphere Stratospheric Major Warming. Allen, Douglas R.; Coy, Lawrence; Eckermann, Stephen D.; McCormack, John P.; Manney, Gloria L.; Hogan, Timothy F.; Young-Joon Kim // Monthly Weather Review;Feb2006, Vol. 134 Issue 2, p498 

    A high-altitude version of the Navy Operational Global Atmospheric Prediction System (NOGAPS) spectral forecast model is used to simulate the unusual September 2002 Southern Hemisphere stratospheric major warming. Designated as NOGAPS-Advanced Level Physics and High Altitude (NOGAPS-ALPHA), this...

  • Convectively Coupled Equatorial Waves. Part II: Propagation Characteristics. Gui-Ying Yang; Hoskins, Brian; Slingo, Julia // Journal of the Atmospheric Sciences;Oct2007, Vol. 64 Issue 10, p3424 

    Following the description of the horizontal and vertical structures of convectively coupled equatorial waves presented in Part I, here their propagation characteristics are investigated. Linear lagged regressions are used to produce their composite evolution, and the Radon transform technique is...

  • Rocket measurements of positive ions during polar mesosphere winter echo conditions. Brattli, A.; Blix, T. A.; Lie-Svendsen, Ø.; Hoppe, U.-P.; Lübken, F.-J.; Rapp, M.; Singer, W.; Latteck, R.; Friedrich, M. // Atmospheric Chemistry & Physics;2006, Vol. 6 Issue 12/2, p5515 

    On 18 January 2005, two small, instrumented rockets were launched from Andøya Rocket Range (69.3° N, 16° E) during conditions with Polar Mesosphere Winter Echoes (PMWE). Each of the rockets was equipped with a Positive Ion Probe (PIP) and a Faraday rotation/differential absorption...

  • A Simple Identification Scheme for Upper-Level Troughs and Its Application to Winter Precipitation Variability in Northwest Africa. Knippertz, Peter // Journal of Climate;Mar2004, Vol. 17 Issue 6, p1411 

    A simple algorithm for the identification of upper-level trough axes is introduced. In contrast to the assumption of a basically circular geometry in many comparable routines found in the literature, the presented identification scheme is based on the east–west gradient in the 500-hPa...

  • Upper-Level Frontogenesis Associated with the Birth of Mobile Troughs in Northwesterly Flow. Schultz, David M.; Sanders, Frederick // Monthly Weather Review;Nov2002, Vol. 130 Issue 11, p2593 

    Previous studies have shown that 500-hPa mobile trough births (or genesis) occur preferentially in north-westerly flow during upper-level frontogenesis, and that cold advection assists in, and is a product of, mobile trough intensification. This study focuses on the synoptic environments and...

  • Deep and shallow south foehn in the region of Innsbruck: Typical features and semi-idealized numerical simulations. Zängl, G. // Meteorology & Atmospheric Physics;May2003, Vol. 83 Issue 3/4, p237 

    Numerical simulations of the south foehn in the region of Innsbruck are presented. They are semi-idealized in the sense that realistic orography but idealized initial and boundary conditions are used. The focus of this study is on typical features of the fully developed foehn, the break- through...

  • TROWALS TROFS, and Lows. MASEK, MICHAEL // Canadian Aviator;May/Jun2013, Vol. 23 Issue 4, p20 

    This article presents answers related to questions about the meaning of the terms trowal, trough and closed low.

  • Origin, Evolution, and Finescale Structure of the St. Valentine's Day Mesoscale Gravity Wave Observed during STORM-FEST. Part III: Gravity Wave Genesis and the Role of Evaporation. Jewett, Brian F.; Ramamurthy, Mohan K.; Rauber, Robert M. // Monthly Weather Review;Apr2003, Vol. 131 Issue 4, p617 

    On 14 February 1992, a long-lived moderate-amplitude mesoscale gravity wave formed in Kansas during the Storm-scale Operational and Research Meteorology-Fronts Experiment Systems Test (STORM-FEST). Wave formation was evident in correlated surface pressure and wind fields. The wave of depression,...

  • A Practical Example of Low-Frequency Trend Removal. Denholm-Price, J.C.W.; Rees, J.M. // Boundary-Layer Meteorology;Jan1998, Vol. 86 Issue 1, p181 

    Three different ’classical‘ methods of removing low-frequency trends are used to detrend some instrumental data, and their effect is evaluated. The examples given here highlight problems that may occur whenever detrending is necessary. The trend present in the data arises from the...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics