000
FXUS04 KWBC 170658
QPFPFD

QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
257 AM EDT FRI MAY 17 2013


PRELIM DAY 1 QPF DISCUSSION
VALID MAY 17/1200 UTC THRU MAY 18/1200 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR


DAY 1...

...BROAD WEST COAST UPPER TROUGH ADVANCING INTO GREAT BASIN...

THE BROAD...DEEP CYCLONIC FLOW AND ASSCD STEEPENING LOW-MID LVL
LAPSE RATES WILL CONTINUE TO GENERATE LIGHT TO MODERAL AREAL-AVG
PCPN DURING DAY 1...WITH OROGRAPHIC AND DIURNAL ENHANCEMENT
EXPECTED. HIGHEST AREAL-AVG TOTALS ARE ANTICIPATED ACROSS THE NRN
ROCKIES INTO THE NRN HIGH PLAINS...BTWN A QUARTER AND HALF
INCH...SUPPORTED WITHIN THE REGION OF MOST FVRBL UPPER LEVEL
DIVERGENCE WHILE ALONG THE AXIS OF HIGHEST PW`S (AROUND
.75"...WHICH IS ABOUT 2 STD DEVS ABOVE NORMAL).

...NRN PLAINS/UPPER MIDWEST...

A CONTG NWD MSTR FLUX INTO A QUASI-STATIONARY LLVL BARCOLINIC ZONE
(WITH THE FGEN SUPPORTED BY CONTINUED RIGHT ENTRANCE REGION
FORCING VIA THE UPPER JET AXIS IN SOUTH-CENTRAL CANADA) WILL
CONTINUE TO SUPPORT RE-DEVELOPMENT OF SHOWERS/TSTMS THROUGH DAY
ONE...ESPECIALLY TONIGHT GIVEN AN INCREASING LLJ (CENTERED AROUND
925-850 MB) AND ASSCD MSTR FLUX CONVERGENCE/ELEVATED CONVECTION.
MODELS...INCLUDING HIGH-RES GUIDANCE...ALL HINT AT A DEVELOPING
MCS OVERNIGHT WITHIN THE NRN PLAINS/UPPER MS VLY REGION...THOUGH
ONCE AGAIN DIFFER CONSIDERABLY IN BOTH LOCATION AS WELL AS THE
AMOUNTS. WPC CONTINUED WITH AN ENSEMBLE APPROACH WITH THE
AREAL-AVG QPF...THOUGH AGAIN INCLUDING BOTH THE HIGH-RES WINDOWS
AS WELL AS THE SPC/NSSL WRF RUNS.

...INVOF THE LWR MS VLY...

THE SRN STREAM SHRTWV THAT IS SLOWLY ADVANCING ACROSS THE SRN
PLAINS/LWR MS VLY WILL CONTINUE TO FIRE SHWRS THRU THE PD WITH A
VRY FVBL FLOW OF MOIST AND UNSTBL AIR INTO THE AREA CONTG TO
SUPPORT ACTVTY.  MODEL QPFS SUPPORT CONTG HVY RNFL TOTALS WITH
THIS SYSTEM THOUGH THERE ARE SOME DIFFERENCES CONCERNING
PLACEMENT.  YDAS ACTVTY IN GNRL FELL TO THE SOUTH OF MOST OF THE
GLOBAL GUIDANCE WITH SOME OF THE HI RES MODELS DOING A BETTER JOB
WITH PLACEMENT.  FOR THAT REASON STAYED ON THE SRN EDGE OF TODAYS
GLOBAL GUIDANCE WITH THE MAXIMUM RNFL PLACEMENT FEELING THAT
CNVCTV FORCING WILL BE AVBL TO SUPPORT THE MORE SRN PLACEMENT.

...OH VLY SEWD ACROSS THE CNTRL APLCNS...

LLVL CNVGNC IN  VICINITY OF A WEAK FRONT WILL CONTINUE TO SUPPORT
AREAS OF SHWRS WITH BULK OF  ACTVTY FALLING DURING HOURS OF PEAK
DIURNAL HEATING.  MODEL QPFS ARE GNLY SUPPORTIVE OF THIS SCENARIO
BUT THERE IS LOT OF DISAGREEMENT AS TO WHERE THE HEAVIEST RNFL
WILL BE CONCENTRATED.  USED A GEM REGIONAL/UKMET BLEND FOR THE QPF
WITH THE GFS BEING GNLY SUPPORTIVE OF THEIR FCST AT LEAST IN
REGARDS TO PLACEMENT.

HURLEY

GRAPHICS AVAILABLE ON THE WEB AT WWW.WPC.NCEP.NOAA.GOV

24HR QP VT 18/12Z
 0.01 520156 517178 513198 523218 532245 520291 489346 450330
      431306 427279 456232 456227 456220 460216 461212 477203
      480197 481188 482183 480179 478176 470179 463181 457185
      453190 452197 450205 447208 434205 427203 425198 422194
      423190 418183 413181 409185 403186 403182 406175 405167
      403164 400164 397165 395167 392169 387168 383164 377163
      373162 369158 369150 373145 374139 372136 367133 367128
      369125 374122 384117 388113 391111 401107 403106 405103
      406098 409095 414095 419092 423088 427086 430082 432079
      435074 439065 442061 441056 441043 437034 434029 430025
      420027 417029 414026 414022 417021 419018 417015 414011
      412007 411999 418988 425977 428973 430966 431960 430953
      425946 420937 417932 415926 413919 407919 397922 390920
      377922 374921 371922 364924 358926 355929 344932 339932
      335929 332927 330921 328915 325915 322914 318914 316914
      315912 312908 310902 309896 311892 314885 318877 321873
      322869 323859 325852 330846 336838 344831 351825 353820
      354813 354800 354788 350774 346762 340749 340745 341740
      342736 345735 353737 361741 367748 372753 375756 378760
      381762 383769 418864 421871 424874 426876 428876 433874
      440866 441863 443862 449859 453858 457861 464863 467866
      470871 472874 474881 477885 480891 485902 487910 489915
      492929 495937 497945 498953 499964 498971 498977 499981
      500989 501995 503999 504003 504008 507012 508024 508028
      509033 512034 515032 521021 522015 526011 533004 544990
      547986 552986 559995 561005 561018 560027 558033 554040
      551046 544053 541058 535060 532060 529063 526063 523063
      520058 513051 508049 507052 506061 506063 503064 498065
      494068 491072 491077 492087 494091 495100 497106 498114
      503128 518148 520153 520156
 0.01 502625 505634 505640 506645 505656 501666 498673 494675
      490679 483682 476679 472677 469673 466672 457664 459655
      459652 463648 471643 472639 471636 468635 464634 463631
      459626 457624 457620 460602 460596 461591 463587 468570
      471567 474567
 0.01 253996 243995 226001 224025 233034 251029 260004 253996
 0.01 487709 486705 484701 480699 480698 478697 476698 475699
      475702 472703 470707 468709 465711 466715 468719 470717
      474719 477717 479715 482713 485711 487709 487709
 0.01 513223 511218 508221 509226 510229 513227 513223 513223
 0.01 432148 433144 430140 429143 428147 430150 432148
 0.01 272800 271794 270791 263790 260788 256788 253787 248788
      241793 238799 239816 239823 241834 241841 244851 248857
      257856 260856 262854 262851 262845 262838 260827 259822
      259819 261816 266815 270812 271809 273806 272800 272800
 0.25 522264 520263 517262 514258 513256 512255 509253 506252
      504253 503255 502257 502261 503266 504268 505267 507267
      509269 511270 512271 515273 517275 522264
 0.25 482980 482968 481956 478934 475908 472895 469887 465881
      462878 458880 454885 451892 446907 442914 437922 433927
      432931 432934 434941 437948 441955 445965 448974 445982
      441987 438991 438994 439003 442010 453018 456025 455030
      453035 452042 451054 451064 447068 444072 444076 445083
      441092 438098 434103 432106 429107 418112 415115 413118
      413122 416125 422130 426128 426123 429116 432113 436113
      440114 443117 444124 456145 452150 452160 462160 469166
      472166 475164 477160 480151 480142 482135 481132 478130
      473127 470124 472117 474108 476081 479062 481054 483047
      483040 482034 476030 475022 475015 476012 478003 480996
      482980
 0.25 400863 399855 397852 391840 388837 385836 379839 375838
      367837 355839 352839 347841 340848 334853 331857 329862
      326880 327893 331904 334909 337911 341913 347912 354906
      358906 364906 369904 371902 378893 387876 395872 399868
      400863
 0.25 259802 260799 257798 255797 254797 252798 249799 249800
      248803 251803 253802 255804 257805 259803 259802
 0.50 475942 471917 470907 469901 467896 465890 463889 461891
      459895 455905 451914 444930 440939 442946 445949 450956
      454964 466979 467982 467985 464989 463996 465001 468004
      471998 474989 475973 475963 476955 475946 475942
 0.50 469051 467048 467047 465043 464038 461035 458037 458039
      458043 458047 459048 462051 464055 465056 467055 468055
      469051
 0.50 379855 378850 375847 368845 361848 354847 349847 343850
      338855 334862 332868 330876 331885 332895 333898 336902
      339904 345905 351900 358896 364893 370888 375883 379878
      379873 377871 375866 375864 379855
 1.00 465923 463920 461924 464926 465923
 1.00 346874 345867 345864 343863 340864 338866 336870 335874
      334878 335885 337891 339894 343896 345895 348891 345885
      346878 346874
 1.50 340883 340879 338879 338880 338883 339886 340883

$$