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Squall Line with Mesoscale Convective Vortex

The images and animations shown here represent visualizations of a squall line with a mesoscale convective vortex (MCV) using data generated by the Klemp-Wilhelmson numerical model. The model is initialized with 5 storm cells along a 160 kilometer long line. The squall line is evolving in an environment of moderate vertical windshear with winds increasing by 20 m/s between the ground and 2.5 KM above ground.

Cloud Water


Rain Field and Cold Pool


Cold Pool and Particle Trajectories


QuickTime | Real | MPEG

As the storm matures, a familiar anvil shaped system is visible when viewing the cloud water variable, QC. Shown here is a QC isosurface with value 0.0001 g/kg along with a colored horizontal temperature slice at the surface.


QuickTime | Real | MPEG

A dark blue rain field isosurface (.00054 g/kg) is shown along with a pool of cold temperatures that develops near the surface behind the storm as a result of the evaporation of rainfall. The surface cold pool is represented by a potential temperature isosurface (light blue) of -2° C. The pattern of colder temperature near the top is the result of gravity waves in the stratosphere above the storm.


QuickTime | Real | MPEG

Massless particles (blue and red spheres) show the circulation around the MCV. The red spheres are released at an elevation of 500 meters in front of the storm, and the blue spheres are released at 3 km behind the storm. This view from the North shows the red spheres thrown rapidly into the upper atmosphere by strong vertical updrafts at the front of the squall line. The blue spheres behind the storm show the rear inflow circulation. Also included is a -2.5° C isosurface of the potential temperature perturbation.


Rain Field and Horizontal Wind Vectors


Rain Field and Horizontal Wind Vectors - Top View


Rain Field and Vertical Slice of the Wind Vector


QuickTime | Real | MPEG

A horizontal vector slice shows the wind direction and magnitude at a level of 2.5 KM along with a rain field isosurface of 0.0054 g/kg. The wind vectors identify strong updrafts at the leading edge of the storm in conjunction with heavy precipitation. The surface temperature is represented by a colored horizontal slice at the bottom of the domain.


QuickTime | Real | MPEG

A view from the top shows the development of a strong current of air that feeds into the system from the west along with a dominant cyclonic mesoscale vortex at the north end of the system. This dominant vortex forms as the air converges into the system at mid levels spinning up the ambient Coriolis Rotation.


QuickTime | Real | MPEG

A vertical cross section of wind vectors is seen here along with a color contoured vertical slice of the highest valued scalars in the rain field. The cooling effects of the precipitation behind the storm are evident from the colored horizontal slice of surface potential temperature.


Rain Field Slice and Horizontal Wind Vectors


QuickTime | Real | MPEG

This view from the top shows the horizontal wind vectors and a rain field slice at a level of 2.5 KM.

Model Name:
Time Evolution:
8 hours
Visualization Domain  
Horizontal Real World:
324x324 km
Vertical Real World:
17 km
Tim Scheitlin
Morris Weisman
Chris Davis
Bill Skamarock
Joe Klemp
Date Catalogued:
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