<br /> 6
<br /> 5
<br />::E 4
<br />~'
<br />" 3
<br />-'"
<br />" 2
<br />Ci
<br />;2
<br />::;
<br />,- 0
<br />;;;
<br />;- .1
<br />- .2
<br />VJ
<br />,
<br />Z -3
<br /> -4
<br /> .5
<br /> .6
<br /> -9 -K .7 -6
<br />
<br />~
<br />::E
<br />~
<br />
<br />"
<br />-'"
<br />"
<br />Ci
<br />'0
<br />c
<br />"
<br />
<br />,-
<br />;:;
<br />;-
<br />
<br />c
<br />
<br />VJ
<br />Z
<br />
<br />,~1ES1
<br />to 20 30 35 40 45 50 54 58
<br />u, CSU-CHILL 210K MUT: UIlZ, KUI' (White), ZUJ{(llIurk)
<br />K
<br />7
<br />6
<br />
<br />tional settings, especially warn,
<br />ing situations, extensive data
<br />processing and/or tuning of ra,
<br />dar rain-rate relationships in real
<br />time is impracticaL Therefore it
<br />is necessary to examine the rela,
<br />tive accuracy of radar-rainfall
<br />measurements in postevent pro-
<br />cessing, Here the word "accu-
<br />racy" refers to the amount of
<br />rainfall measured by the radar
<br />compared to that measured by
<br />the rain gauge network.
<br />Herein, we briefly discuss
<br />several radar estimates of the
<br />maximum Storm Total Precipi,
<br />tation (STP) for the FCL flood
<br />(Table 2), The rainfall estimates
<br />were computed using KCYS
<br />Level II reflectivity data, and
<br />CSU-CHILL reflectivity and
<br />polarimetric data, The data were
<br />gridded with a horizontal spac-
<br />ing of 500 m at an elevation of
<br />approximately I lan, Reflectivity,
<br />based rain rates were computed
<br />for each grid point using the
<br />NEXRAD Z-R relationship (Z =
<br />300R'4) applied to both untrun-
<br />cated and truncated reflectivity
<br />(53 dBZ) values, Given the ap'
<br />parent tropical nature of the
<br />convection, two tropical Z-R
<br />relationships (Table 2) were
<br />also utilized (Short et aL 1997;
<br />Rosenfeld et aL 1993) for com,
<br />parative purposes, Rain rates
<br />were integrated over the 5,h du-
<br />ration of the storm to compute
<br />the STP, Level II data from
<br />the Denver NEXRAD radar
<br />(KFfG) were unavailable dur,
<br />ing the initial phase of the analy'
<br />sis, though a recent service
<br />
<br />FIG, 18, Horizontat cross section at 1.2 Ian AGL ofCSU-CHILL radar data at 2108 MDT 28 July 1997, (a) Reflectivity (shaded),
<br />2DR (black contour), and KDP (white contour). The 2m: is contoured every 0.3 dB starting at 1.2 dB. KIll' is contoured every 0.50 km-'
<br />starting at 10 lan-I. (b) Rainfall rate in mm h-1. The blended R(KDP' ZnR) rain-rate product is shaded as shown and the NEXRAD Z-R
<br />rain rates are contoured at the same rainfall intensities for direct comparison (1, 10,20,30,40,50,70,90, and 110 mm h-I). The plane
<br />of the vertical cross sections shown in Fig. 17 for the same time are indicated by a dashed blue line.
<br />
<br />..
<br />
<br />210
<br />
<br />5
<br />
<br />
<br />4
<br />]
<br />2
<br />I
<br />()
<br />-I
<br />
<br />.2
<br />
<br />.3
<br />-4
<br />-5
<br />-6
<br />
<br />.9 -8 .7 -6 -5 -4 .3 -2 -I ()
<br />
<br />2 3 456
<br />
<br />7 K 9
<br />
<br />
<br />.5 -4 -3 -2 .( 0 ( 2 3 4 5 6
<br />E-W of Taft and Drak~ (KM)
<br />r I ,~I=I I , ,
<br />10 20 30 40 50 70 90 110
<br />
<br />7 K 9
<br />
<br />Vo/' 80, No, 2, Februory 1999
<br />
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