ON THE NEED FOR VOLUMETRIC RADAR DATA WHEN ISSUING ...

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Volume 17 Number November, 1992 13 -- - 996 ;;;~====±=~~~ ~032 4:!'- 1004---__ 1006-__ .--" 1014 '-- , 61 071 1008............ _?r '49,p.+37 89 0 6 ""'----_-----,J..l.' ~~I!7'r \ ( 39167 .-.. ,,~" 50 046 4,\ 4,4 4,1 \,39_'!'9 ... '\)\ \ \ '--'-'" 51/' ........ _ .L. _ ... 49~20 \ \ \ , . '" t. .]0'952 50 PRESFR "\ \ 47\ 098 \ " V .... - --... , \"'~' - 0/ ",'" I 58 "'010 " \\ 46""r7 I .... __ .... "' .... ~ /' ",59~-;''l'o~'" '\i \ ~~~ \ / / '" -56 .... -.>--', ',\ \ 46=-201 '< - ,"", ...:..~~ 58 +7L-' j!. ,. - ....... ~', 54 0 O~ I \ 48/[21 50 ,I I 67017",53,-17, , ....... _ ",(,l:1:3' ':;t I 61 OO~ \ RJ-3" '':-~:-'''' ........ 50"" 4]..-", 3 +10' ... .' \64 5' "~~~ ........... ---_-c.::~"'''' \ I' \ \ ~ 993 - .... ::~--=--- .... '" \ .,... \ '66 ....... ~ ........ '> ..;:: '" . \ 6 53 - .... -~-.... I \ \ - - 68 .... 053- - _ \ 59 036 ' \ \ _." = ~ ~ 66 083_ -- o 64~054 '. 67 ~029,.1 60 -15 1 1\ I 54 +37 I " ,.. ..... II, I I, ~47 69, \ 64 -31 \ I \ \ ,- -... ~:: ___ .... +17 \-_·-c' \ \ 67' ........ 68 34 =~ --_ .. i / 61 071 I ~061 " \ 59 076 49..@+37/ 63 ~+17 69 '056 - 65 ~+32 ~ ,P.lESRR ,I r-." ~1O 49 25 12 ~ ~ I' / 68 £:I " ~' ~ ' f~ 68 , I , 62 65 Fig. 8. Surface data and analysis at 1500 UTe, 28 February 1987; (a) isobars of sea level pressure (interval 2 mb), along with conventional frontal symbols and selected surface data, (b) surface data and isotherms (interval 3°F).
14 National Weather Digest POI~D CREEK POND CREEK 8N 7W ,NID JAUKOM I S CO') I ~tGTOI · t BASE REF 19 R 124 I·t, 54 04/26/91 23,04 I I i I I· -: -I : :II[ I , il l !' i ! ', III I , POND PERf 19 R 124 N . 54 NM 23' 04 , 1' 1;· ."" , _-+___--'-_'_' _1_' 1_'_, _____--.-______--, R DA 'KOKC 35/ 19/ 5 8 ~4 1277 FT 97 / 16/ 37W :3 f'lODE A / 21 4 f'lAX= 56 D8Z LAMOIH POND CREEK NO 5 /---------- 10 ,NID JAUKmlIS BASE REF 19 R 124 N 04 / 26/ 91 23 dj4 ' !" ' . : I I ' . ; j l l , PERf 54 1~~1 I d , PERI 75 54 IH'1 RES I d I , . ii I A/R (HOME) 154 DEG 32076FT 4 NM OUEUE Ei'lF'T',' I I 1·1 I ! " 'II: I I t i ' l I ; , '" 05/1718 COMf'l ERROR ON LINE 8 411 -3 HAF'DCOP'i HAI':DCOF",' F'EC!UE :::T ACCEPTED Fig. 9. Four reflectivity slices (OS, 1S, 2.4° and 4.3° elevation angles) from the Twin Lakes (near Oklahoma City, Oklahoma) WSR-88D system 2304 UTC, 26 April 1991. This storm is exhibiting a WER on the south side of the storm. supercell, even though a hook echo was never apparent with the storm. 4.3 WSR-88D Strategy for Examining Storms New observational data and computers to deal with radar, satellite and environmental conditions will be implemented gradually into future modernized weather offices. Those forecasters using the WSR-88D system must take advantage of the exciting new capabilities the system has to offer. The combination of the better resolution reflectivity data and the addition of the mean radial velocity will greatly enhance forecasters ' abilities to warn for dangerous storms. Also, forecasters will have more time to scrutinize the data, since the radar will sample several elevation angles automatically and create displays for each elevation angle sampled. The WSR-88D system will collect reflectivity and velocity data at either 9 or 14 different elevation angles every 5 or 6 min. (Lemon et al. 1992). The operator can display at the Principal User Processor (PU P; Alberty 1990) the best elevation angles to examine the low, middle, and upper regions of a storm and then interpret the data to determine the storm's potential severity (as illustrated in Figs. 9 and 10). All of this can be done easily and repeatedly and in a few seconds through the use of a User Function (Lemon et aI., 1992). The three-dimensional evaluation of the storm with four slices of reflectivity and velocity will be the best radar method to anticipate the development of mesocyclones before the detection algorithms indicate their presence, as well as validate or refute the algorithm output. The same criteria described by Lemon (1980) for issuing severe thunderstorm and tornado warnings can be used with the WSR-88D system, although the three-dimensional storm structure features are emphasized rather than the specific values. If one is monitoring the reflectivity structures properly with this system, forecasters will be able to watch the three-dimensional reflectivity structure evolve from non-severe to severe storms before that evolution is evident in the velocity fields (Lemon and Doswell 1979). The WSR-88D system also will store all products received at the PUP during the event on an optical
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