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000
FXUS04 KWBC 141835
QPFPFD

QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
234 PM EDT TUE MAY 14 2013


PRELIM DAY 1 QPF DISCUSSION
VALID MAY 15/0000 UTC THRU MAY 16/0000 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR



DAY 1...

...PAC NW...

SYNOPTIC SCALE LIFT ASOCTD WITH A SHRTWV TROF MOVG TO THE NW COAST
BY WED EVNG WILL INDUCE LGT PCPN TOTALS OVR THE PAC NW BY END OF
THE PD.  AVBL MOISTURE WILL BE LIMITED AS THE LLVL ONSHORE FLOW
GENERATED BY THE SYSTEM REMAINS WEAK AT BEST.  BLENDED A GFS/00Z
ECMWF QPF SOLUTION WITH THOSE MODELS BEING VRY SIMILAR WITH AMTS
AND COVERAGE.

...CONCERNING THE ADVANCING SRN STREAM TROF...

FIRST OF ALL..MODELS ARE NOT IN THE BEST AGREEMENT HANDLING THE
QPF ASOCTD WITH THIS SYSTEM AND AS A RESULT CONFIDENCE IS NOT HI
WITH THE MANUAL QPF.  BIGGEST DIFFICULTY IS FIND A LLVL BNDRY TO
CONCENTRATE RNFL ALONG..THOUGH THE AXIS OF MAX PWS AND RH..AS WELL
AS THE LOCATION OF BEST COOLING AND FVBL DIV FLOW ALOFT..WOULD
ARGUE FOR THE ERN HALF OF TX FOR PLACEMENT OF THE STRONGEST SHWR
ACTVTY.  THE GEM REGIONAL AND HI RES ARW INDC MUCH HEAVIER TOTALS
THAN THE GLOBAL MODELS LEADING TO SOME CONCERN AS THEY DID A MUCH
BETTER JOB LAST WEEK WITH THE VRY HVY CNVCTV RAINS THAT OCCURRED
HERE.  ALL THAT BEING SAID..FOR NOW OPTED FOR A BLEND OF MODEL
GUIDANCE FOR PLACEMENT GIVEN THE DIFFERENCES AND ALSO STAYED
CONSERVATIVE WITH TOTALS FOR THE SAME REASON.

...NORTHEAST/LOWER LAKES/OH VLY/MIDWEST...

WAA PCPN PATN AHEAD OF A SHRTWV TROF ADVANCING EWD ACROSS SRN
CANADA/NRN PORTION OF THE GREAT LAKES REGION IS EXPECT TO SUPPORT
VRY LGT TO LGT PCPN TOTALS THRU THE PD.  THE RAPID EWD MOVEMENT OF
THE WARM FRONT IS ALMOST TOO QUICK TO ALLOW THE WLY TO WSWLY FLOW
IMPINGING ON THE FEATURE TO SATURATE THE AIRMASS THUS LIMITING THE
CHANCES OF SGFNT SHWRS OVR THE NORTHEAST.  GLOBAL MODEL QPFS ARE
IN AGREEMENT ON THE LGT PCPN TOTALS THOUGH THE REMAIN DISJOINTED
AS TO WHERE TO PLACE THE HEAVIEST ACTVTY.   TOOK A BLEND OF THE
UKMET AND GEM REGIONAL FOR THE MOMENT GIVEN SOME SIMILARITY BTWN
THEIR FCSTS.  MEANWHILE..CDFNT TRAILING WWD FM THE LOWER LAKES
THRU THE OH VLY/MIDWEST SHOULD SERVE TO FOCUS SHWRS PARTICULARLY
WED AFTN AND EVNG.  PREFERRED THE GEM REGIONAL QPF HERE WHICH
SEEMS TO BEST REFLECT THE GLOBAL MODEL FCSTS OF DECENT LLVL MSTR
CNVGNC ACROSS THIS AREA IN ADVANCE OF THE CDFNT PER LLVL WIND AND
PW FIELDS.

KORTY

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

24HR QP VT 16/00Z
 0.01 536899 534886 532876 525865 523860 520857 516853 503849
      497845 496843 497840 498835 499831 497824 494819 493816
      495812 492789 495787 497783 499780 501774 501766 502763
      501758 498748 494740 490734 486730 482722 476716 465707
      462704 459702 453701 445699 439698 434697 431696 428695
      424691 420689 415685 407681 401681 398686 397689 397694
      397702 397722 400731 401738 401741 398743 396745 394749
      388745 386742 382741 378739 374739 372739 371742 372748
      376760 385771 388773 391776 393782 389789 387794 388799
      390802 392803 392806 392810 390828 389847 387863 387875
      387884 385891 382898 378904 367915 354924 338931 322934
      317933 310933 304935 301938 283956 266977 262983 259987
      255990 251990 246992 245996 247000 250004 252008 255011
      274024 282026 288029 297038 302040 307036 308033 310030
      315024 318020 323016 330017 336016 344015 352013 358011
      365009 378001 384996 389988 392983 391975 378969 374965
      375959 384952 390949 394950 406954 409953 411947 415952
      420950 425942 432928 435911 438894 442884 445879 449878
      453876 456879 459878 462881 467885 471892 475898 479906
      485913 492919 497923 512929 521926 528918 532909 536899
 0.01 534225 537217 537211 536206 533195 531190 527183 521175
      513170 508165 503168 503173 504175 509186 510188 510193
      510198 515210 516214 517218 520221 524232 528233 532229
      534225
 0.01 517278 520273 520268 521255 520245 517238 516232 516228
      513222 505219 500209 497207 489204 474205 470208 468210
      465210 458211 452215 448219 449225 451228 455229 456232
      452232 442235 439238 436241 435244 434249 437253 438258
      437263 435274 438281 444284 452286 457284 463282 468280
      470278 473281 474285 474291 476294 480297 486298 492298
      505294 512288 517278
 0.01 465034 465026 465017 464010 463004 457993 456976 455969
      451968 449981 450989 452993 452998 453005 451010 451027
      449039 447043 447048 452049 459047 461044 462038 465034
 0.01 459110 458105 456101 453097 450097 446096 442092 438092
      435096 431094 430088 427088 424084 427088 426096 424099
      421103 420108 420111 417111 416111 412106 410103 409098
      406096 406103 405110 403113 408118 417119 420119 423116
      429117 432116 436114 440117 443118 446122 452118 458111
      459110
 0.01 427060 426055 422049 418045 415042 413037 409022 409010
      407000 404000 402007 399012 398017 396020 394027 394035
      392038 390040 385040 381039 377038 369039 364042 358044
      353048 349051 348056 349059 354061 355065 358068 364070
      369075 372083 377093 375097 375098 378101 381096 383092
      386092 390091 395092 398091 400087 402082 404079 407078
      411078 414076 416073 416068 416064 415062 415060 418059
      421061 425062 427060
 0.25 513271 514266 514261 511251 508243 506239 503237 499237
      498240 498247 486241 473237 464247 462252 461258 463263
      465264 468263 474261 477260 481261 490275 494281 500285
      506285 509281 511275 513271
 0.25 466734 464731 461728 459726 456724 455723 452722 451722
      449722 446723 446726 446730 449731 450732 453733 454733
      457735 458736 461738 465739 466734
 0.25 472219 469217 467217 466217 463221 466224 468222 469221
      472219
 0.25 409774 409772 408771 405769 404773 403775 403778 402782
      402786 403790 405792 408789 409787 409784 410782 410778
      409775 409774
 0.25 354953 354949 348950 338947 331945 324945 314949 305954
      293966 281978 277984 276988 277993 279995 284995 293991
      309982 322971 328966 335965 340964 347959 351957 354953
 0.25 330995 330991 329991 328992 327993 324995 321999 324999
      325999 327997 330995 330995
 0.50 506277 506273 505272 503269 502266 501264 499261 498260
      496258 493257 490257 489261 490261 492264 493267 494270
      495273 496275 499278 501280 502280 505280 506277
 0.50 485255 482252 480249 477248 474251 476254 479254 482254
      485255
 0.50 328958 325954 319953 314954 309957 303962 296968 289974
      284980 282984 284987 292986 302982 308978 316971 321966
      325962 328958

$$