View source for Differential echo motions: 24 June 2005

[[Image:ANOT 24jun2005 vel.png|250px|right]]
Areas with opposite-sign radial velocities were observed in separate regions of a thunderstorm complex on 24 June 2005.  PPI image loops show the development of a meso-scale anticyclonic motion within this echo area.

==Introduction==
During the afternoon hours of 24 June 2005, the CSU-CHILL radar conducted high time resolution (~1:25 repetition interval), low elevation angle PPI sector scans that covered a nearby cluster of thunderstorms.  Time lapse animation of the reflectivity data showed the development of distinct clockwise rotation pattern within the echo complex.

==Reflectivity data==
The development of the meso-scale rotation pattern apparently was aided by the effects of a northeastward-moving fine line that impacted the western portion of the echo system.  In contrast, the reflectivity cores located in the eastern section of the echo area only drifted slowly away from the radar.  The following image shows the highlights of the situation. The range rings are at 30 and 60 km.
<center>
[[Image:24jun2005 dbz anot.png]]
<imgloop delay=200 imgprefix="http://www.chill.colostate.edu/anim/24jun2005_meso_anticyclone/" width=640 height=512>
dBZ.CHL20050624_231252 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_231417 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_231542 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_231707 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_231831 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_231956 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_232120 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_232244 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_232409 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_232533 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_232658 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_232822 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_232946 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_233111 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_233236 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_233401 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_233525 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_233650 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_233815 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_233941 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_234105 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_234230 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_234354 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_234519 DENT PPI Sweep 02 Plot 0.png
dBZ.CHL20050624_234644 DENT PPI Sweep 02 Plot 0.png
</imgloop>
</center>

==Radial velocity data==
The enhanced inbound radial velocities associated with the propagating fine line are apparent in the following image. The odd-looking velocity patches embedded in the southeastern portion of the echo field are second trip returns from the upper portions of thunderstorms located at ranges beyond 150 km.
<center>
[[Image:24jun2005 vel anot.png]]
<imgloop delay=200 imgprefix="http://www.chill.colostate.edu/anim/24jun2005_meso_anticyclone/" width=640 height=512>
Vel.CHL20050624_231252 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_231417 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_231542 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_231707 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_231831 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_231956 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_232120 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_232244 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_232409 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_232533 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_232658 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_232822 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_232946 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_233111 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_233236 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_233401 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_233525 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_233650 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_233815 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_233941 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_234105 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_234230 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_234354 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_234519 DENT PPI Sweep 02 Plot 0.png
Vel.CHL20050624_234644 DENT PPI Sweep 02 Plot 0.png
</imgloop>
</center>

==Differential reflectivity data==
The insects collected in the convergent airflow along the fine line produce large positive <math>Z_{dr}</math> magnitudes.  Due to this characteristic pattern, warm season fine lines are often easiest to identify by examining the low elevation angle <math>Z_{dr}</math> data.  The <math>Z_{dr}</math> returned by ground clutter targets is commonly negative in sign:
<center>
[[Image:24jun2005 zdr anot.png]]
<imgloop delay=200 imgprefix="http://www.chill.colostate.edu/anim/24jun2005_meso_anticyclone/" width=640 height=512>
ZDR.CHL20050624_231252 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_231417 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_231542 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_231707 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_231831 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_231956 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_232120 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_232244 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_232409 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_232533 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_232658 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_232822 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_232946 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_233111 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_233236 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_233401 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_233525 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_233650 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_233815 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_233941 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_234105 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_234230 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_234354 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_234519 DENT PPI Sweep 02 Plot 0.png
ZDR.CHL20050624_234644 DENT PPI Sweep 02 Plot 0.png
</imgloop>
</center>

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