Simulated Evolution and Severe Wind Production by the 25–26 June 2015 Nocturnal MCS from PECAN
Advanced Search
Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.
 
 
i

Superseded

This Document Has Been Replaced By:

i

Retired

This Document Has Been Retired

i

Up-to-date Information

This is the latest update:

Simulated Evolution and Severe Wind Production by the 25–26 June 2015 Nocturnal MCS from PECAN
  • Published Date:

    2019

  • Source:
    Mon. Wea. Rev. (2020) 148 (1): 183–209.
Filetype[PDF-7.77 MB]


This document cannot be previewed automatically as it exceeds 5 MB
Please click the thumbnail image to view the document.
Simulated Evolution and Severe Wind Production by the 25–26 June 2015 Nocturnal MCS from PECAN
Details:
  • Description:
    The 25–26 June 2015 nocturnal mesoscale convective system (MCS) from the Plains Elevated Convection at Night (PECAN) field project produced severe winds within an environment that might customarily be associated with elevated convection. This work incorporates both a full-physics real-world simulation and an idealized single-sounding simulation to explore the MCS’s evolution. Initially, the simulated convective systems were elevated, being maintained by wavelike disturbances and lacking surface cold pools. As the systems matured, surface outflows began to appear, particularly where heavy precipitation was occurring, with air in the surface cold pools originating from up to 4–5 km AGL. Via this progression, the MCSs exhibited a degree of self-organization (i.e., structures that are dependent upon an MCS’s particular history). The cold pools eventually became 1.5–3.5 km deep, by which point passive tracers revealed that the convection was at least partly surface based. Soon after becoming surface based, both simulations produced severe surface winds, the strongest of which were associated with embedded low-level mesovortices and their attendant outflow surges and bowing segments. The origin of the simulated mesovortices was likely the downward tilting of system-generated horizontal vorticity (from baroclinity, but also possibly friction) within the simulated MCSs’ outflow, as has been argued in a number of previous studies. Taken altogether, it appears that severe nocturnal MCSs may often resemble their cold pool-driven, surface-based afternoon counterparts.
  • Document Type:
  • Main Document Checksum:
  • File Type:
  • Supporting Files:
    No Additional Files

You May Also Like: