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The following PPI scan is a SOLO presentation of data collected by the NASA N-Pol radar operating with the CSU-CHILL offset feed antenna.  (DR=Zdr; PH=phidp) A deep cyclonic-type upslope snow event is in progress:

[[Image:Png.1090326161143.npol1.0 2.3 PPI DZ.png]]

The next RHI was made on an azimuth of 240 degrees:
[[Image:Png.1090326160703.npol1.0 240.0 RHI DZ.png]]

For dual Doppler analysis purposes, the CSU-Pawnee radar is also being operated during this event.  The following two PPI images were saved from a VCHILL display that was showing the real time Pawnee data presentation in the CHILL radar user van.

[[Image:26mar2009 1713 PAW Z.png|650px|Pawnee dBZ]]

[[Image:26mar2009 1713 PAW V.png|650px|Pawnee radial velocity]]
==Mid-day update==
By 1830 UTC / 1230 MDT echo coverage is starting to decrease in the western azimuth semi-circle.  Differential propagation phase shift is most evident in the south eastern quadrant at this time.
[[Image:Png.1090326183144.npol1.0 2.3 PPI DZ.png]]

[[Image:Png.1090326182702.npol1.0 240.0 RHI DZ.png]]
==20 UTC hour images==
Reflectivities have quite generally decreased.  The Zdr's are tending to become positive as more pristine / less aggregated snow particles become more common.  The phidp field is essentially flat.
[[Image:Png.1090326203145.npol1.0 2.3 PPI DZ.png]]

[[Image:Png.1090326202704.npol1.0 240.0 RHI DZ.png]]

The following time series of Platteville wind profiles shows the increasingly deep northerly flow replacing the easterly upslope flow regime that prevailed during this morning's heavier precipitation.
[[Image:PLT 26mar2009 8 21UT.png]]

==PPI image loop==
The following loop is made of 2.3 degree elevation angle N-Pol PPI scans at one hour intervals from 1530 to 0230 UTC on the 27th.  The fields show various pulsations during the evening hours.  CSU radar operations ended shortly after 03 UTC on 27 March 2009.

<imgloop delay=1000 imgprefix="http://www.chill.colostate.edu/anim/20090326_blizzard/" width=364 height=640>
png.1090326153154.npol1.0_2.3_PPI_DZ.png
png.1090326163145.npol1.0_2.3_PPI_DZ.png
png.1090326173145.npol1.0_2.3_PPI_DZ.png
png.1090326183144.npol1.0_2.3_PPI_DZ.png
png.1090326193145.npol1.0_2.3_PPI_DZ.png
png.1090326203145.npol1.0_2.3_PPI_DZ.png
png.1090326213144.npol1.0_2.3_PPI_DZ.png
png.1090326223145.npol1.0_2.3_PPI_DZ.png
png.1090326233146.npol1.0_2.3_PPI_DZ.png
png.1090327003144.npol1.0_2.3_PPI_DZ.png
png.1090327013146.npol1.0_2.3_PPI_DZ.png
png.1090327023144.npol1.0_2.3_PPI_DZ.png
</imgloop>
==Aftermath==
Snow accumulation at the CSU-CHILL radar site at approximately 0730 MDT on 27 March 2009.  (Cat included as a size scale reference.)
[[Image:00011.jpg|center|thumb|500px]]