TITLE

Mesoscale Vortex Development during Extreme Precipitation: Colorado, September 2013

AUTHOR(S)
Morales, Annareli; Schumacher, Russ S.; Kreidenweis, Sonia M.
PUB. DATE
December 2015
SOURCE
Monthly Weather Review;Dec2015, Vol. 143 Issue 12, p4943
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
On 11-12 September 2013, portions of northern Colorado experienced flash flooding as a result of high rain rates accumulating over 180 mm of rain in 6 h. From 0400 to 0700 UTC 12 September a mesovortex was observed traveling northwestward toward the city of Boulder, Colorado, with enhanced upslope flow on its north side and localized deep convection. Although the mesovortex was observed in an area common for lee vortex formation, namely that associated with the Denver Cyclone, it is shown via ARW model simulations that the mesovortex intensified through the release of latent heat, similar to the processes leading to mesoscale convective vortices, rather than by dry topographic-flow dynamics. High rates of cloud water condensation at relatively low altitudes led to a strong vertical gradient in latent heating, resulting in a near-surface positive potential vorticity anomaly. Reducing the contribution of cloud water condensation to latent heating by 50% resulted in no mesovortex development in the model and a substantial decrease in precipitation. On the other hand, removing the topographical forcing in the model did not inhibit the mesovortex formation, confirming the secondary role of topography. The mesovortex enhanced upslope winds and convection, and was thus a key feature in the generation of intense precipitation over Boulder. The ability to forecast the development of these mesovortices and their subsequent environmental and hydrological effects could be critical for decision-makers and the public, given their association with high rainfall rates.
ACCESSION #
111554771

 

Related Articles

  • The Impact of Large-Scale Forcing on Skill of Simulated Convective Initiation and Upscale Evolution with Convection-Allowing Grid Spacings in the WRF*. Duda, Jeffrey D.; Gallus, William A. // Weather & Forecasting;Aug2013, Vol. 28 Issue 4, p994 

    A set of mesoscale convective systems (MCSs) was simulated using the Weather Research and Forecasting model with 3-km grid spacing to investigate the skill at predicting convective initiation and upscale evolution into an MCS. Precipitation was verified using equitable threat scores (ETSs), the...

  • A Numerical Study of the Evolution of a Mesoscale Convective Vortex on the Meiyu Front. Jinxin Wang; Yinong Pan; Shicheng Wang // Acta Meteorologica Sinica;Dec2013, Vol. 27 Issue 6, p889 

    The Advanced Research WRF (Weather Research and Forecasting) model is used to simulate the evolution of a mesoscale convective vortex (MCV) that formed on the Meiyu front and lasted for more than two days. The simulation is used to investigate the underlying reasons for the genesis,...

  • Adjoint Sensitivity and Predictability of Tropical Cyclogenesis. DOYLE, JAMES D.; REYNOLDS, CAROLYN A.; AMERAULT, CLARK; MOSKAITIS, JONATHAN // Journal of the Atmospheric Sciences;Dec2012, Vol. 69 Issue 12, p3535 

    The sensitivity of tropical cyclogenesis and subsequent intensification is explored by applying small perturbations to the initial state in the presence of organized mesoscale convection and synoptic-scale forcing using the adjoint and tangent linear models for the Coupled Ocean-Atmosphere...

  • The evolution of an MCS over southern England. Part 1: Observations. Clark, P. A.; Browning, K. A.; Morcrette, C. J.; Blyth, A. M.; Forbes, R. M.; Brooks, B.; Perry, F. // Quarterly Journal of the Royal Meteorological Society;Jan2014, Vol. 140 Issue 679, p439 

    Observations are described of a Mesoscale Convective System (MCS) with a cold pool which propagated across southern England on 25 August 2005. The observations were made as part of the Convective Storm Initiation Project (CSIP). The observed MCS structure broadly followed well-established...

  • The Representation of Föhn Events to the East of the Antarctic Peninsula in Simulations by the Antarctic Mesoscale Prediction System. Kirchgaessner, Amélie; King, John; Gadian, Alan // Journal of Geophysical Research. Atmospheres;12/27/2019, Vol. 124 Issue 24, p13663 

    Föhn winds are warm, strong, downslope winds on the leeside of mountains, which can last from several hours to a few days. The years 1995 and 2002 saw the dramatic breakup of huge parts of the Larsen Ice Shelf (LIS) on the east of the Antarctic Peninsula. It is widely accepted that...

  • The role of mesoscale instabilities in the sting‐jet dynamics of windstorm Tini. Volonté, Ambrogio; Clark, Peter A.; Gray, Suzanne L. // Quarterly Journal of the Royal Meteorological Society;Apr2018, Vol. 144 Issue 712, p877 

    Sting jets (SJs) occur as an additional region of low‐level strong winds in some Shapiro–Keyser‐type extratropical cyclones. While SJs are widely accepted as being distinct from the warm and cold conveyor belts, the mechanisms responsible for their occurrence are still not...

  • Characteristics and predictability of a supercell during HyMeX SOP1. Miglietta, Mario Marcello; Manzato, Agostino; Rotunno, Richard // Quarterly Journal of the Royal Meteorological Society;Oct2016, Vol. 142 Issue 700, p2839 

    An analysis is presented here of intense convection affecting the Friuli Venezia Giulia region (FVG, northeastern Italy) during the Intensive Observation Period 2b (IOP2b) in the first Special Observation Period (SOP1) of HyMeX (HYdrological cycle in Mediterranean EXperiment). The present study...

  • High resolution numerical modeling of mesoscale island wakes and sensitivity to static topographic relief data. Nunalee, C. G.; Horváth, Á.; Basu, S. // Geoscientific Model Development Discussions;2015, Vol. 8 Issue 3, p2973 

    Recent decades have witnessed a drastic increase in the fidelity of numerical weather prediction (NWP) modeling. Currently, both research-grade and operational NWP models regularly perform simulations with horizontal grid spacings as fine as 1 km. This migration towards higher resolution...

  • Ensemble-Based Analysis of the May 2010 Extreme Rainfall in Tennessee and Kentucky. Lynch, Samantha L.; Schumacher, Russ S. // Monthly Weather Review;Jan2014, Vol. 142 Issue 1, p222 

    From 1 to 3 May 2010, persistent heavy rainfall occurred in the Ohio and Mississippi River valleys due to two successive quasi-stationary mesoscale convective systems (MCSs), with locations in central Tennessee accumulating more than 483 mm of rain, and the city of Nashville experiencing a...

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