Quantitative Precipitation Forecast
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000
FXUS04 KWBC 191800
QPFPFD

QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
159 PM EDT FRI SEP 19 2014


PRELIM DAY 1 QPF DISCUSSION
VALID SEP 20/0000 UTC THRU SEP 21/0000 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR


DAY 1
~~~~~

ARIZONA
~~~~~~~
PRECIPITABLE WATER VALUES (PWS) OF 1.75" COMBINED WITH DAYTIME
HEATING TODAY SHOULD LEAD TO TYPICAL MONSOON-LIKE THUNDERSTORM
DEVELOPMENT THIS AFTERNOON AND TONIGHT ACROSS SOUTHEAST AZ.  THE
0-6 KM BULK SHEAR (20 KTS OR LESS) AND MAGNITUDE OF THE 700 HPA
INFLOW (10 KTS) IMPLY SINGLE CELL/PULSE CONVECTION TODAY OVER
ANYTHING ORGANIZED.  HOURLY RAIN RATES UP TO 2" ARE POSSIBLE WHERE
CELLS MERGE, WHICH COULD LEAD TO A FEW POCKETS OF FLASH FLOODING
THIS AFTERNOON AND EVENING.  LIMITED FLASH FLOODING/DEBRIS FLOWS
COULD OCCUR TOMORROW AFTERNOON AND EVENING AS WELL ACROSS THE
MOGOLLON RIM AND SOUTHERN WASATCH AS MOISTURE RETURNS INTO THE
REGION.  AREAL AVERAGE AMOUNTS OF 0.10-0.25" WERE DEPICTED FOR THE
MOST PART, IN LINE WITH THE 00Z GEFS- AND CLIMATOLOGY-BASED QPF
REFORECAST.  THIS LED TO SLIGHTLY DECREASED AMOUNTS FROM 12Z WPC
QPF CONTINUITY.


SOUTHEAST NM/WESTERN TEXAS
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
A DEEP MOISTURE PLUME ASSOCIATED WITH ODILE -- WITH PWS OF
1.50-1.75" -- ALONG WITH ANOTHER ANOMALOUS PW AXIS SETTING SAIL
WELL TO THE NORTH AND NORTHEAST OF T.S. POLO INTO WESTERN TX, WILL
CONTINUE TO OVERWASH A STALLED W-E STATIONARY FRONT ACROSS
SOUTH-CENTRAL AND SOUTHEAST TX THROUGH THE PERIOD. SOUTH TO
SOUTHEAST LOW-LEVEL FLOW WILL CONTINUE AHEAD OF ODILE`S
SLOW-MOVING CENTER OF CIRCULATION -- CURRENTLY VOYAGING THROUGH
SOUTH-CENTRAL NM -- WITH THE INFLOW WEAKENING DURING THE DAY AND
RESTRENGTHENING SOMEWHAT OVERNIGHT DUE TO THE NOCTURNAL LOW-LEVEL
JET.  WEAK ANTECEDENT UPPER-LEVEL FORCING WITHIN THE BROAD UPPER
RIDGE WILL GET A BOOST AHEAD OF THE ODILE-RELATED CIRCULATION AND
WITH INCREASED UPPER LEVEL DIFFLUENCE.  SATURATED SOILS BEDEVIL
THE REGION -- THEY CANNOT STAND ANY ADDITIONAL RAINFALL FROM ANY
SORT OF THUNDERSTORM, REGARDLESS OF ITS CONVECTIVE MODE.
THUNDERSTORMS WHICH FORM WITHIN THE REGION COULD ORGANIZE AS 0-6
KM BULK SHEAR IS NEAR 25 KTS.  CONVECTION SHOULD BECOME MORE
PERIPHERAL TO THE CIRCULATION DURING THE DAY AND CLOSER TO ITS
CIRCULATION CENTER OVERNIGHT.  PER THE MOST RECENT MESOSCALE QPF
GUIDANCE... LOCALIZED AMOUNTS OF 4-8 INCHES ARE POSSIBLE -- MOST
LIKELY OVER THE TRANS-PECOS AND BIG COUNTRY PORTIONS OF TX AND
SOUTHEAST NM -- AS THE OVERALL MOISTURE-RICH ENVIRONMENT (WARM
RAIN PROCESSES) WILL CONTINUE TO SUPPORT RAINFALL RATES UP TO 2.5"
PER HOUR.  THE LATEST GUIDANCE ALONG WITH THE 00Z GEFS- AND
CLIMATOLOGY-BASED QPF REFORECAST LED TO A SOUTHWEST SHIFT IN
PRECIPITATION PATTERN WHEN COMPARED TO 12Z WPC QPF CONTINUITY.


SOUTH-CENTRAL/SOUTHEAST TX
~~~~~~~~~~~~~~~~~~~~~~~~~~
A SEA OF ANOMALOUSLY HIGH MOISTURE, IN THE 2-2.5" PW RANGE, NEAR
TO ABOVE THE 90TH PERCENTILE FOR MID-SEPTEMBER, LIES CLOSER TO THE
SURFACE BOUNDARY OVER AN INCREASINGLY SATURATED AREA.  ACROSS
SOUTH-CENTRAL TX, CONVECTIVE ORGANIZATION IS POSSIBLE CONSIDERING
25 KTS OF 0-6 KM BULK SHEAR ADVERTISED BY RECENT RAP GUIDANCE.
INSTABILITY CAUSED BY DAYTIME HEATING IN LEAGUE WITH THE AVAILABLE
MOISTURE SUPPLY SHOULD GUARANTEE THUNDERSTORM ACTIVITY WITH HEAVY
RAINFALL THIS AFTERNOON AND EVENING.  OTHER THUNDERSTORMS ARE
POSSIBLE ACROSS SOUTHEAST TX THIS AFTERNOON IF SUNNY SKIES BREAK
OUT LATER TODAY.  OVERNIGHT, ANOTHER BATCH OF THUNDERSTORMS IS
EXPECTED ACROSS THE MIDDLE AND UPPER TX COASTLINES NORTH OF THE
FRONTAL ZONE, WHICH SHOULD HAVE SOME ASSOCIATED CIN BY THAT TIME.
SOME OF THE MESOSCALE GUIDANCE INDICATED THAT LOCAL AMOUNTS OF
3-6" ARE POSSIBLE IN THIS REGION.


UPPER MIDWEST/UPPER MS VALLEY/GREAT LAKES
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
A STRONG UPPER JET STREAK (110+ KTS AT 250 MB) WILL STEER
SOUTHEAST OF ALBERTA/SASKATCHEWAN INTO THE NORTHERN PLAINS
TONIGHT, AMPLIFYING THE ASSOCIATED SHORTWAVE TROUGH.
STRENGTHENING PRE-TROUGH QG FORCING -- ENHANCED FROM THE LEFT-EXIT
REGION OF THE UPPER LEVEL JET STREAK NUDGING INTO THE TROUGH BASE
-- AND ASSOCIATED PRE-FRONTAL DEEPENING SOUTHERLY FLOW/WARM AIR
ADVECTION/MOISTURE TRANSPORT (WITH PWS INCREASING TO 2-2.5 SIGMAS
ABOVE THE MEAN FOR MID- TO LATE-SEPTEMBER) WILL ALLOW FOR LINEAR
MULTICELL CONVECTION ALONG/AHEAD OF THE SURFACE COLD FRONT.
SUFFICIENT DEEP-LAYER INSTABILITY (1000-2000 J/KG) ALONG WITH
SHARP WIND CONVERGENCE ASSOCIATED WITH THE HEIGHT FALLS WILL MAKE
FOR A RATHER PROGRESSIVE PRECIPITATION SHIELD...AND AS SUCH
AREAL-AVERAGE AMOUNTS SHOULD BE SOMEWHAT LIMITED.  USED THE 00Z
GEFS- AND CLIMATOLOGY-BASED QPF REFORECAST AND 12Z PSEUDO
BIAS-CORRECTED ENSEMBLE QPF TO LOWER AMOUNTS SLIGHTLY IN THE UPPER
MIDWEST/UPPER MS VALLEY, WITH AMOUNTS CLOSER TO CONTINUITY NEAR
THE GREAT LAKES.


SOUTHEAST
~~~~~~~~~
A COASTAL LOW IS EXPECTED TO FORM A BIT EAST OF THE NORTHEAST FL
AND SOUTHEAST GA COASTLINE -- POTENTIALLY FAR ENOUGH AWAY FOR A
SIGNIFICANT QPF IMPACT THROUGH LATE SATURDAY.  USED A COMPROMISE
BETWEEN THE NON-CANADIAN GUIDANCE (PER OUR MODEL DIAGNOSTIC
REASONING) AND THE 12Z WPC QPF IN THIS REGION, WHICH WAS
REASONABLY CLOSE TO THE 00Z GEFS- AND CLIMATOLOGY-BASED QPF
REFORECAST AND THE 12Z PSEUDO BIAS-CORRECTED ENSEMBLE QPF.


FLORIDA
~~~~~~~
A FRONTAL BOUNDARY WITHIN THE FL PENINSULA IS EXPECTED TO BE THE
FOCUS FOR THUNDERSTORMS WITH HEAVY RAINFALL, IN THE WARM AIR
ADVECTION PATTERN AHEAD OF A CONVECTIVE FRONTAL WAVE.  PWS OF ~2"
ALONG WITH EXPECTED BOUNDARY LAYER MOISTURE CONVERGENCE FROM THE
12Z NAM FORCED THE CENTER OF ACTION TO CENTRAL FL, WHICH ALSO FITS
IN WELL WITH THE 00Z GEFS- AND CLIMATOLOGY-BASED QPF REFORECAST.
A NORTHWARD SHIFT WAS NOTED IN THE PSEUDO BIAS-CORRECTED ENSEMBLE
QPF BETWEEN ITS 06Z AND 12Z RUNS.  THIS LED TO A NORTHWARD SHIFT
IN THE MAXIMUM FROM 12Z WPC QPF CONTINUITY.

ROTH

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

24HR QP VT 21/00Z
 0.01 526180 526177 524174 522171 520170 517168 516172 515177
      514179 514183 517184 520183 522182 525182 526180
 0.01 517952 517939 515928 512924 511919 511904 510876 512864
      512848 513843 513836 512822 510811 507799 502776 498768
      494764 491764 489757 488750 485740 484735 482732 476726
      473723 470725 466733 462741 459750 458755 455759 451765
      447773 444782 437798 433807 427815 422822 419829 411845
      407852 404861 397881 391897 388906 388912 387916 384940
      383952 382956 382963 382976 383986 383999 384003 386006
      390013 396018 400021 402016 399009 398005 398002 401002
      404003 406007 409015 416020 421020 425018 425006 426000
      427994 428989 430985 433974 436966 440958 442957 443960
      444965 447969 450971 456976 461977 463979 463983 463990
      464994 468002 475007 481010 491010 493008 495003 499993
      502983 505973 506970 509968 511966 514965 517952
 0.01 509068 510059 510052 509044 509035 508028 506023 502020
      498021 495026 491030 487032 485037 484041 487048 486055
      490058 495060 497067 499072 502075 505073 509069 509068
 0.01 416064 414061 413059 413056 409056 406056 405058 405061
      409063 405065 405067 406070 408070 412071 413071 412068
      414066 416064
 0.01 411108 411106 411103 410101 410098 408098 406098 406100
      405102 405105 405107 405109 405110 407110 409111 409110
      411108 411108
 0.01 399164 399158 398152 393144 385138 386129 388124 391118
      387115 376114 372118 369122 365121 361117 355110 350102
      342082 340078 336075 327078 324080 322078 319075 308070
      309067 311066 315067 321068 324066 328062 326061 324055
      324051 326049 336048 348048 367044 369043 369040 370037
      367036 360031 365021 366014 366007 366973 366965 365959
      361949 359945 353945 350946 346949 339958 333964 319964
      314962 311958 307947 306942 303938 301932 301926 298915
      297901 295897 291893 285893 283898 280908 278921 270925
      262931 257938 249958 243965 235971 234983 234991 235997
      242017 244022 244028 245033 244041 244053 244059 246064
      251074 256083 263090 272095 282098 282104 284110 286113
      290115 296115 299113 302114 302118 304123 310132 313136
      317140 323145 330151 341157 360165 384173 389174 395173
      399164
 0.01 384200 384197 383195 380192 378190 376188 373187 369187
      369188 371191 373193 375196 377197 380198 382200 384200
 0.01 396071 394065 396057 398052 397045 395040 391037 386035
      382035 376037 374042 371047 368050 367053 371054 374053
      378052 383054 384061 383066 380067 378070 380074 386075
      392075 395073 396071
 0.01 384738 384734 383731 376731 365735 361738 357737 353735
      347736 342739 334746 327754 324759 316761 312764 309769
      259782 249787 245790 243795 239805 238812 238820 240825
      243829 246835 247841 249858 253869 255873 259877 263880
      267883 269884 273884 279882 283879 287875 288873 290876
      293880 298881 302878 305866 306863 306859 304852 299844
      305843 310840 317832 324823 335804 348785 354775 360767
      367757 376749 381743 384738
 0.01 361821 359820 357821 354823 353825 349826 347828 347831
      349833 351835 353833 355830 356828 358825 360823 361821
 0.25 504870 504847 502824 500814 497804 494797 493794 490793
      484793 478796 471796 464795 462795 461790 460783 457781
      455781 450785 446791 442797 437810 434816 432824 432829
      433833 436835 440835 444835 444840 442846 434857 430857
      428854 427850 423848 419851 415856 411870 406885 404892
      402901 406902 408901 413897 422887 426883 430883 432885
      434888 434892 431900 426914 419946 417955 416960 417965
      421964 423961 426956 435946 439942 443937 447931 452926
      464918 467920 467924 467930 469938 472945 475952 479959
      484964 487965 491965 494960 497952 499945 500940 500934
      499923 497914 499903 501893 504870
 0.25 356022 357016 357011 356000 353991 351987 348985 330986
      314992 305004 303008 303013 305017 305021 301028 298036
      302037 307037 312037 317038 325040 333040 341037 348033
      353028 356022
 0.25 346767 346762 344759 337760 330762 325766 320771 314775
      301782 296786 289789 288791 283792 277792 263789 256792
      253794 251797 248802 245809 246816 250820 254826 255830
      256835 257842 260845 263847 271846 274845 276842 277837
      279835 284831 294822 302819 309820 315819 321815 329804
      336792 342779 346767
 0.25 321108 321102 322097 320093 317089 313091 309093 311096
      309096 306100 307104 309109 311112 314114 318113 320109
      321108
 0.25 300015 296006 296000 298995 299992 297989 295985 293980
      294975 298965 299953 299946 298940 296935 294931 289930
      285932 281934 278937 273946 268955 266965 265972 267976
      270980 272983 268985 261986 252988 242987 240991 243995
      247002 264011 265013 266016 264022 261026 257029 254031
      252035 250040 252045 254049 254055 252060 253065 258073
      264080 272087 276089 280090 284088 284085 280075 276067
      275062 279060 286054 289052 292047 293041 296038 289031
      288028 290028 296026 300015
 0.50 499865 499850 497838 495832 492827 486824 481817 478814
      473814 467819 463823 460825 455826 452830 449840 446848
      441856 435862 431864 427864 425861 423856 420855 417860
      417865 417872 419874 422874 425874 426876 428876 434874
      438875 443875 447877 449878 448884 445894 441904 439913
      439916 440916 443913 447909 450907 453909 458908 464903
      471903 475907 477912 478918 477922 476930 479934 484940
      488941 491940 492938 489924 488919 488912 488905 490900
      493891 496881 498872 499865
 0.50 454794 453791 451791 447795 444800 441805 438813 437818
      436825 438826 441826 444821 447814 449809 452803 454796
      454794
 0.50 351022 352015 352007 350001 348997 343994 337994 326996
      318001 314004 312009 312022 313029 317032 328035 334035
      339033 346028 351022
 0.50 336780 336772 335769 332768 326771 322773 313779 308783
      305787 302792 299796 295800 291803 287804 284803 279801
      268799 261799 255801 254803 254806 258809 262811 264817
      265824 269829 274829 279827 284823 287820 289815 294812
      298811 302814 307816 312816 318813 321810 327801 332791
      336780
 0.50 294960 296952 294945 290941 286943 283947 280954 277958
      276966 276970 277974 283974 287972 291968 294962 294960
 0.50 287016 286008 282003 278000 274997 268995 260996 258997
      257000 262004 267007 271010 274013 280018 285018 287016
 0.50 278053 278048 276044 275039 273036 268034 262034 257034
      257037 257043 260046 261050 265054 270053 276054 278053
 1.00 485861 484854 483849 480844 477842 473840 471841 468846
      467851 469858 470861 474865 477865 481864 485861
 1.00 343022 345017 344013 342007 338004 331002 326004 322007
      319014 319022 321027 328028 335028 339026 343022
 1.00 325792 325788 325784 323782 319781 314783 311788 308794
      306799 305803 307807 311810 317808 321804 323798 325792
 1.50 338017 338012 336011 335009 333007 329008 327008 325011
      325014 324018 324022 327023 329023 332022 335021 337019
      338017
 1.50 319800 318798 318796 317795 315795 314796 314797 313798
      313800 313803 314805 315804 316804 318802 319800

$$





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