000
FXUS04 KWBC 160659
QPFPFD

QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
258 AM EDT THU MAY 16 2013


PRELIM DAY 1 QPF DISCUSSION
VALID MAY 16/1200 UTC THRU MAY 17/1200 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR


DAY 1...

...SHRTWV TROF LIFTING ACROSS THE NORTHEASTERN PORTION OF NATION...

THE AXIS OF HIGHER PW`S AHEAD OF THE PROGRESSIVE UPPER LEVEL
SHORTWAVE AND ASSCD SFC OCCLUDED FRONT WILL BE RATHER
SHORT-LIVED...AS WILL THE AREA OF LFQ UPPER JET INDUCED
WAA/ISENTROPIC LIFT. ADDITIONAL QPF OVER THIS REGION WILL AVERAGE
UP TO A TENTH OF AN INCH...AND MAINLY CONFINED OVER ERN-NERN MAINE.

...CONCERNING THE BROAD UPPER TROF ADVANCING INTO THE WESTERN
U.S...

THIS SYSTEM AND SHRTWV ENERGY BEING EJECTED FM IT WILL FIRE AREAS
OF SHWRS FM THE PAC NW/NRN CA EWD ACROSS THE NRN GREAT BASIN INTO
THE NRN ROCKIES DURING THE PD.  MODEL QPFS MAXIMIZE PCP0N INVOF
WRN AND SRN OR AS WELL AS NRN CA...BUT AMTS THERE WILL REMAIN ON
THE LGT SIDE GIVEN THE LACK OF MOISTURE WITH LIMITED LLVL ONSHORE
FLOW. AT THE SAME TIME...PW`S BTWN .75" AND 1.0" ENTERING NRN CA
PER CURRENT GPS AND BLENDED TPW ANALYSIS AVERAGES BTWN 2 AND 3 STD
DEVS ABOVE NORMAL FOR MID MAY...THUS EVEN AREAL-AVG AMOUNTS ON THE
ORDER OF A TENTH TO QUARTER INCH INTO NRN CA (HIGHEST OVER THE
ELEVATED TERRAIN) IS A BIT OF AN ANOMALY. OTHERWISE...LIGHT
AMOUNTS (AGAIN AVERAGING BTWN A TENTH AND QUARTER INCH TOPS) WILL
SPREAD ACROSS THE NRN INTERMTN REGION AND INTO THE NRN
ROCKIES...WHERE SCATTERED TO OCNLY NUMEROUS SHOWERS WILL BECOME
FAVORED IN THE INCREASINGLY UPPER DIFFLUENT FLOW...ANOMALOUS PW`S
(AROUND 2 STD DEVS ABOVE NORMAL)...AND STEEPENING LOW-MID LEVEL
LAPSE RATES.

...NRN HI PLAINS INTO THE LWR MO RIV VLY...

MODELS GENERATE WEAK HGT FALLS ACROSS THIS REGION FM THE COMBO OF
THE VORT BEING EJECTED ENEWD FM THE THE S CNTRL GREAT BASIN AND
PIECES OF ENERGY EMBEDDED IN THE NRN STREAM.  MODEL QPFS IN GNRL
SUPPORT WIDESPREAD SHWRS ACROSS THIS AREA...PARTICULARLY THIS AFTN
AND OVERNIGHT...AND ARE BEGINNING TO COME IN BETTER ALIGNMENT IN
TERMS OF WHERE THE HEAVIER QPF WILL BE FAVORED. BROADLY FVRBL RRQ
REGION UPPER JET DYNAMICS AND ASSCD LOW-MID LAYER FRONTOGENESIS
SUPPORTS AN AXIS OF HIGHER QPF WITHIN AN ELONGATED PW AXIS (AROUND
1 TO 1.25") FROM THE DAKOTAS INTO NEBRASKA...NW IOWA...AND SRN
MINNESOTA. A MULTI-MODEL BLEND...INCLUDING AN ENSEMBLE OF
HIGHER-RES RUNS...SUPPORT AN AXIS OF HEAVIEST QPF NEAR THE BORDERS
OF NE/IA/SD/MN...ALIGNING ALONG THE AXIS OF HIGHEST PW`S AND 850
MB INFLOW (THETA-E ADVECTION AND MSTR FLUX). AREAL AVG AMOUNTS
ABOVE AN INCH ARE ANTICIPATED IN A RELATIVELY NARROW RIBBON.

...SRN PLAINS/LWR MS VLY...

MODEL FCSTS OF AMPLE MOIST AND UNSTBL AIR ACROSS THE REGION WITH A
CONTG NWD MSTR FLUX NOTED IS SUGGESTIVE OF HVY SHWRS ACROSS THIS
AREA WHICH WILL BE TRIGGERED BY THE ADVANCE OF THE SRN STREAM
UPPER LO/TROF ACROSS THE REGION.  MODELS ARE IN THE SAME BALLPARK
WITH THE SGFNT QPF BUT THERE IS LOT OF VARIATION WITH TIMING AND
PLACEMENT IN DETAILS OVR THE SHORT TIME FRAME...DUE IN LARGE PART
TO THE ONGOING MCS AND THE EVENTUAL MCV THAT WILL RESULT FROM IT.
BEYOND THE NEAR TERM (I.E. AFTER 12Z THU)...EXTRAPOLATION OF THE
MESO-ENHANCED VORT CENTER TRACK WOULD SUPPORT THE HIGHEST
AREAL-AVG AMOUNTS ACROSS ARKANSAS AS SUPPORTED BY MANY OF THE
HIGH-RES WINDOWS. HOWEVER...WHILE THE MODELS ARE SOMEWHAT BETTER
CLUSTERED COMPARED TO THE LAST RUN...THERE REMAINS QUITE BIT OF
VARIABILITY IN TERMS OF LOCATIONS AND AMOUNTS...AS TO BE EXPECTED
GIVEN THE CONVECTIVE NATURE OF THE PCPN AND LIKELIHOOD OF
DEVELOPING COLD POOLS AND ENSUING LLVL STABILIZATION.

HURLEY

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

24HR QP VT 17/12Z
 0.01 490671 486657 480644 478640 474639 467636 460636 455639
      451644 447649 446652 444661 445673 446684 449690 452691
      455697 455702 451711 452718 451722 450727 452732 457737
      476723 483717 486712 490707 492698 492685 490676 490671
 0.01 535216 537205 539194 538186 536180 533170 529164 527157
      525152 522146 520143 513140 508138 505134 498126 492124
      489119 486114 486109 487105 490092 494090 497086 495083
      492080 482080 479082 476079 472076 468078 461078 455077
      448071 445067 441067 436068 436072 440073 444077 446081
      448086 438087 436090 433091 430087 424088 425090 428094
      429098 428102 413112 409099 406098 405104 403109 403114
      406115 409115 411118 415119 418120 418124 415128 413132
      394137 390140 386145 383156 382160 384165 387172 390176
      396180 399184 399187 398191 396196 391195 383191 377190
      374187 370185 367186 368191 373195 375196 376199 379203
      386211 391219 393224 392226 390227 380225 376228 374235
      379244 399251 411255 415254 420255 426256 431257 437259
      440259 451260 456258 460259 465257 469258 475258 481260
      487262 491267 498276 503278 506276 506270 503263 497254
      493243 489238 488236 485236 481237 481231 480228 477229
      472229 472226 474222 480222 486223 489223 492224 494226
      496228 500233 503235 507235 504229 501216 498212 495208
      496204 499201 502201 508204 512208 516211 529215 535216
 0.01 508026 505008 502002 500995 494983 487974 479966 471956
      469951 466944 464937 463932 462931 459923 457917 453909
      450904 447900 444895 440892 435890 431887 428887 425885
      421883 418883 409876 405871 402862 399829 399816 396801
      396795 393787 388769 387762 386755 386743 385730 384722
      384717 382709 378706 375716 373722 372726 368729 368733
      367739 365748 367757 367761 369770 371779 373792 375799
      374804 375818 375847 373851 370851 364850 362843 358829
      354824 352827 348836 350849 350855 352863 354872 351872
      349876 345887 343900 341904 337908 333916 327925 319946
      318952 321956 325958 327962 329968 334971 338974 344975
      355972 359970 363965 366962 370957 374955 379956 384955
      388955 391957 396958 400963 404966 406968 406973 405980
      405987 405992 404995 401999 395006 390009 387014 390019
      395022 403027 407030 409035 413039 421041 431044 448053
      455054 459057 467065 483050 495036 505032 508026
 0.01 483200 482193 482191 479181 478175 477172 473169 469168
      463174 462178 459181 453184 450192 451196 451201 452207
      453210 457211 459210 467210 473206 479204 483200
 0.01 449179 448173 446168 443165 437163 435156 434152 434144
      433141 430141 427141 426143 426151 427155 429159 432164
      434170 436175 439179 444181 447182 449179
 0.01 420935 419931 419927 418924 418920 417916 415913 413909
      413905 410903 409902 406900 405904 406907 406911 408915
      408918 409922 411926 412929 413933 415936 416936 418939
      420935
 0.01 421060 419056 418052 415048 409049 407052 404053 403061
      403068 404072 410073 415073 416068 419064 421060
 0.01 401046 401041 395041 389042 386045 383049 380050 378052
      375053 375055 378058 384058 387057 392055 395053 398049
      401046
 0.25 509170 508165 509160 508158 505158 504160 502162 500163
      499165 496167 497172 498174 501175 504174 507171 509170
 0.25 484011 483002 479994 476993 474999 473008 470017 467022
      460026 457029 457035 461039 467044 472045 476042 479037
      482028 484015 484011
 0.25 474111 476107 474102 472098 468093 465093 462094 456094
      450095 447098 441100 439104 437108 438113 444121 449130
      452134 454138 457139 462135 464131 466123 467119 474111
 0.25 451226 453222 452219 450216 444211 440206 439202 433196
      431192 431186 430179 427176 425173 420173 418174 418181
      418191 416195 413199 408205 405206 400206 393202 389201
      388205 392211 399217 406221 410224 415226 418228 418234
      425234 430236 436235 443232 448229 451226
 0.25 454968 455959 454951 453943 451938 445938 439939 434944
      431948 429957 427962 425966 421971 419975 417982 415987
      413991 413999 414006 413010 413015 414018 417021 420023
      426025 432028 437040 441043 447041 450038 452032 452029
      449023 446015 443999 445994 448990 450985 452977 454968
 0.25 392799 389793 385791 382796 380801 379809 380828 382846
      385864 386873 390882 397896 399890 399879 397860 396841
      395822 393803 392799
 0.25 375905 375898 373895 369893 364894 357895 351899 346906
      341911 335917 332924 328932 326940 325945 326950 331954
      338959 341961 345962 350959 356953 360947 362937 364929
      368922 375905 375905
 0.25 452151 450147 448150 450152 452151
 0.50 449965 449957 446951 443950 440951 435954 433960 429969
      425973 423978 422990 421002 423005 425008 428009 434004
      439997 444987 446982 447978 449965
 0.50 421205 423202 421201 420201 421205 421205
 0.50 392807 390800 388797 386799 384804 384811 384822 386833
      389848 391862 393869 396874 394861 393854 393850 393842
      393836 393824 392811 392807
 0.50 364908 364904 362902 357902 351904 347909 344913 339916
      334926 330937 329943 330949 339955 346953 350948 353944
      357938 360927 363916 364908
 1.00 443966 443962 442961 439963 436965 435968 434970 433972
      431975 430977 429979 428981 428985 429989 430989 433990
      435989 437988 438985 439983 440979 440978 441975 442971
      442968 443966
 1.00 353925 351920 348919 343920 340923 338928 337932 336936
      336943 338946 342945 345941 348937 351934 352929 353925

$$