Quantitative Precipitation Forecast
Issued by NWS

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS04 KWBC 181843
QPFPFD

QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
242 PM EDT THU SEP 18 2014


PRELIM DAY 1 QPF DISCUSSION
VALID SEP 19/0000 UTC THRU SEP 20/0000 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR


DAY 1
~~~~~

PACIFIC NORTHWEST/NORTHERN CONTINENTAL DIVIDE
PORTIONS OF THE GREAT BASIN
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
WEAK ONSHORE FLOW INTO THE PACIFIC NORTHWEST AND NORTHERN
CONTINENTAL DIVIDE SHOULD LEAD TO LIGHT PRECIPITATION FROM LATE
TODAY INTO THURSDAY ACROSS THE COASTAL RANGES AND CASCADES.  A
FRONTAL ZONE SLOWLY MOVING THROUGH THE INTERIOR WEST IS EXPECTED
TO SPREAD ORGANIZED RAINS THROUGH THE REGION.  ACROSS THE CENTRAL
GREAT BASIN INTO THE NORTHERN ROCKIES...THE ANOMALOUS PW
AVAILABILITY (2-3 STANDARD SIGMAS ABOVE MID-SEPTEMBER AVERAGES)
ALONG WITH FAIRLY STEEP LAPSE RATES (7-8 C/KM BTWN 700-500 MB)
WILL ALLOW FOR MORE NUMEROUS SHOWERS AND THUNDERSTORMS DURING THE
AFTERNOON AND EVENING HOURS AS THE UPPER TROUGH MOVES INLAND AND
URGES THE FRONTAL ZONE ALONG.  SOME ENHANCED UPPER LEVEL SUPPORT
VIA THE RIGHT ENTRANCE REGION OF THE NRN STREAM JET STREAK COULD
HELP THE ACTIVITY DEVELOP THROUGH TOMORROW.  USED A COMPROMISE OF
12Z WPC CONTINUITY AND THE 00Z GEFS- AND CLIMATOLOGY- BASED QPF
REFORECAST FOR THIS REGION.


NM/TX BIG COUNTRY/TX BIG BEND
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
THUNDERSTORMS WITH HEAVY RAIN REMAIN IN THE CARDS FROM SOUTHERN NM
INTO WEST-CENTRAL TX AS DECENT UPSLOPE FLOW ON THE EASTERN SIDE OF
THE REMAINS OF ODILE (WHICH ARE MOVING TOWARDS SOUTHWEST NM) MOVE
INTO THE SCENE, WITH A HIGH RISK OF EXCESSIVE RAINFALL CONTINUING
FOR SOUTHERN NM.  THE POTENTIAL FOR AREAS OF LONG DURATION
FLOODING REMAINS A CONCERN INTO TOMORROW, WHEN ODILE`S 850/700 HPA
CIRCULATIONS ARE FORECAST TO DISSIPATE.  THE HIGHLY ANOMALOUS PW
AVAILABILITY (3-3.5 STANDARD DEVIATIONS ABOVE NORMAL OR 1.75-2")
AND INSTABILITY CAUSED BY DAYTIME HEATING SHOULD LEAD TO FLASH
FLOODING FROM ORGANIZED THUNDERSTORMS THIS AFTERNOON AND TONIGHT.
RECENT MESOSCALE QPF GUIDANCE INDICATES THAT LOCAL AMOUNTS OF 3-5"
ARE POSSIBLE IN THIS REGION.  THE 12Z WPC QPF CONTINUITY WAS
SHIFTED SOMEWHAT SOUTHWARD, AND AMOUNTS WERE SLIGHTLY LOWERED, PER
THE MOST RECENT GUIDANCE.


TX HILL COUNTRY, PINEY WOODS, & BIG THICKET
SOUTHWEST LA EASTWARD TO THE ATCHAFALAYA
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
INSTABILITY HAS BUILT ACROSS PORTIONS OF TX, WITH RECENT SPC
MESOANALYSES INDICATING CAPE VALUES IN THE 1000-2000 J/KG RANGE
ACROSS TX.  AN AREA OF >2" PRECIPITABLE WATER VALUES AND
UPPER-LEVEL DIFFLUENCE UNDER AN UPPER LEVEL HIGH NEAR A COMPOSITE
BOUNDARY -- A FRONTAL ZONE BEING REINFORCED BY OUTFLOW BOUNDARIES
-- HAVE ALLOWED A BATCH OF THUNDERSTORMS TO CONSOLIDATE ACROSS
SOUTHEAST TX EARLY THIS AFTERNOON.  TONIGHT, STRENGTHENING
LOW-LEVEL INFLOW UP THE RIO GRANDE -- ON THE ORDER OF 25-35 KTS --
SHOULD INTERACT WITH BOUNDARIES TO CAUSE VERY HEAVY RAINFALL
ACROSS SOUTH-CENTRAL TX.  THE 12Z ARW, NMM, SPCWRF, NAM CONEST,
NSSL WRF RUNS ALONG WITH THE 16Z HRRR RUN SHOW A STRONG SIGNAL FOR
EXCESSIVE RAINFALL BETWEEN AUSTIN AND DEL RIO TX OVERNIGHT, WITH
MOST OF THE MESOSCALE GUIDANCE INDICATING 9"+ AMOUNTS IN THIS
REGION.  DUE TO THE STRONG SIGNAL, BROUGHT UP AMOUNTS ACROSS THE
REGION BETWEEN AUSTIN AND DEL RIO, WITH THE BLESSING OF THE EWX
(AUSTIN/SAN ANTONIO/NEW BRAUNFELS) FORECAST OFFICE.


SOUTHEAST/SOUTHERN MID-ATLANTIC STATES
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
A RETURN OF MOISTURE FROM THE ATLANTIC IS EXPECTED TO CAUSE
SHOWERS AND THUNDERSTORMS FROM GA NORTHWARD UP THE PIEDMONT OF THE
CAROLINAS/VA WHERE THE BEST BOUNDARY LAYER MOISTURE CONVERGENCE
EXISTS AND THE BEST 850 HPA UPSLOPE FLOW (20-30 KTS) IS
ANTICIPATED.  SINCE PRECIPITABLE WATER VALUES IN THE REGION ARE
LOW -- 1-1.25" -- KEPT AMOUNTS LIGHT AND BELIEVE THE RISK OF FLASH
FLOODING IN THE REGION IS MINIMAL THROUGH THE PERIOD.  SLIGHTLY
INCREASED AMOUNTS FROM 12Z WPC CONTINUITY TOWARDS THE 00Z GEFS-
AND CLIMATOLOGY- BASED QPF REFORECAST.


FLORIDA
~~~~~~~
A FRONTAL BOUNDARY NEAR THE SOUTHERN PENINSULA IS EXPECTED TO BE
THE FOCUS FOR THUNDERSTORMS WITH HEAVY RAINFALL.  PRECIPITABLE
WATER VALUES ALONG WITH EASTERLY LOW-LEVEL FLOW SHOULD FOCUS
CONVECTION ON THE WESTERN SIDE OF THE PENINSULA.  DUE TO THE
FRONT`S POSITION, THE KEYS COULD GET IN ON SOME OF THE ACTION AS
WELL.  USED A COMBINATION OF 12Z WPC CONTINUITY AND THE 00Z GEFS-
AND CLIMATOLOGY- BASED QPF REFORECAST TO MODIFY TOTALS AND
LOCATIONS WERE HEAVY RAINFALL IS MOST FAVORED.

ROTH

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

24HR QP VT 20/00Z
 0.01 225058 237072 242077 250083 256086 264084 270067 279065
      291065 295067 297069 296071 289078 286082 282086 279095
      279101 282105 286110 294113 300112 305115 317127 321129
      324126 326125 329125 334127 347132 353129 360130 367125
      369121 366117 359112 355110 351106 345099 345093 347089
      350086 353086 354080 353075 357071 362070 370075 374082
      378083 379079 380074 378069 372063 370058 370055 368042
      373031 377023 379019 377017 371009 365003 359996 355991
      353987 355983 359978 365971 367967 372965 374965 377968
      378972 387972 391972 394971 400970 403968 408962 410959
      411952 413948 418947 422946 425945 428947 431947 435950
      439953 442957 448965 455974 459976 461981 459993 458000
      457009 457016 459020 462024 461031 462045 461050 460056
      452061 448067 446070 443072 440069 436072 439074 443077
      444080 444084 448085 450088 448091 429088 419090 414089
      410090 403098 400100 398104 395108 391109 384113 379115
      376116 375118 374124 374131 378132 380131 383126 386124
      390124 392126 391129 390137 388141 387146 385160 383166
      383171 381178 378183 374186 372190 377197 382200 385205
      388208 392209 394207 393201 397194 400186 405177 411170
      415165 419163 423160 426155 430131 432126 436124 445121
      448119 450115 453107 458084 462077 464073 465064 470056
      472052 474048 475022 476015 478011 482000 485991 487985
      492983 496982 500980 503980 508988 514994 518994 521991
      538954 541947 542941 543935 543925 542919 540907 538893
      535884 534875 535869 537853 539837 540830 540823 541815
      541808 542793 541780 540770 538764 536761 533759 528759
      526760 517763 512767 505773 502776 498778 494783 492788
      488793 485798 478819 476828 472838 461851 458856 455859
      451860 447864
 0.01 447864 443868 441873 439878 437883 437898 437912 437920
      432923 428923 424926 421926 411931 407931 402933 386945
      385939 382936 376928 373924 370929 365937 361946 356952
      352954 339954 333954 328956 325952 323947 318941 316937
      314930 314922 315913 316900 317888 316881 314876 308869
      303869 299867 296867 294865 295860 299857 305855 318857
      329857 340856 354842 364829 374812 384790 388783 383784
      381786 378787 377788 375787 374779 373774 371776 357792
      354796 350795 346794 346790 345783 345776 346769 348764
      348758 349753 348749 343748 340746 335743 333744 326747
      320749 314751 311755 306761 303765 299769 291775 283772
      277773 274772 261773 257776 253780 242795 239799 239806
      238817 237828 238840 239856 239870 239881 238888 238892
      239898 240906 244914 250932 252938 253941 252945 249954
      248960 246963 244961 242962 242965 242972 246976 245979
      231980
 0.01 537213 538206 539200 538196 537191 534182 530175 527168
      525165 521163 517158 511152 505150 503150 504153 498168
      493173 493179 494182 497185 499188 500191 503190 506194
      506198 507201 512202 516210 518214 520216 534217 537213
 0.01 516278 518269 518260 518254 516249 512239 510232 507229
      504224 502218 498209 494207 490206 481209 476210 472213
      468214 465214 460216 461218 466222 471221 474220 477221
      482222 489224 498246 500248 498249 495246 487239 480231
      477231 474236 455236 445236 435236 416236 423242 426245
      432247 469244 474242 476243 477247 474262 470273 470279
      473283 481280 485279 489279 494282 497286 501291 505290
      509290 511286 516278
 0.01 401074 401072 401069 401067 400067 398069 397071 397073
      397074 399074 401074 401074
 0.01 398083 399081 399078 397078 395078 393080 392080 390082
      389084 389086 391087 393087 395087 396087 397085 398083
      398083
 0.01 333147 333145 333144 332142 331142 330141 328141 326141
      324143 322145 321147 322147 323148 325148 327149 329149
      331149 333147 333147
 0.25 530207 531203 530198 528192 525186 523181 518176 514173
      509173 507177 507182 510188 513192 518197 520203 525207
      530207
 0.25 514266 514259 512253 509249 508243 505237 501234 499234
      499237 501243 505254 506260 504263 494258 491254 488252
      490253 491256 493261 498271 502275 507277 509274 513268
      514266
 0.25 527783 527780 525779 522782 519785 515783 513784 513788
      516793 515796 515799 518801 521799 524794 525789 527784
      527783
 0.25 531928 532921 531914 531904 530891 529875 528864 528854
      527849 526844 520838 515833 512827 506823 500816 497816
      495819 491825 487833 484841 480860 477869 475873 472875
      468876 465879 465889 463898 463905 465909 468911 472911
      475913 475917 478923 480927 481932 478940 477949 477956
      478959 481963 486962 491962 497966 503970 510974 515974
      517972 519968 520962 525942 528940 530936 531928
 0.25 436112 434108 429108 426108 423112 418117 411121 404117
      397115 399123 402127 407126 410125 410128 408132 408136
      403140 401144 399149 396158 396163 399165 403163 405161
      410153 418140 425122 431116 436112
 0.25 413106 413104 413103 411101 409102 408103 407104 407105
      407106 408107 409109 410108 411108 412107 413106
 0.25 361056 361037 364020 355012 349003 339993 330985 325980
      322974 315962 308950 305945 302938 300924 298909 297898
      295889 290877 288870 286859 285854 287847 295836 300833
      305829 311827 315823 321820 327819 334819 338823 341825
      343828 346830 350829 356825 360820 357817 353818 347822
      345823 343820 338816 334811 331806 330797 332791 335779
      341766 342762 340759 340756 338754 335753 333754 332757
      330764 326769 320769 310777 308783 305790 302794 297798
      291800 286798 264786 259787 253793 248804 244818 244826
      245835 248841 249847 248862 248878 248888 248899 250906
      253911 261923 271948 272955 270961 266967 264973 263976
      262981 264988 267994 271000 280008 279020 274024 273028
      275031 271035 268042 263045 257047 254052 253058 247060
      243057 240055 238057 238062 239064 243070 249074 260068
      264065 269059 273055 277056 280054 292051 299051 303055
      309059 311061 311066 314074 315078 314083 311086 305089
      304092 305095 308100 309107 316110 323112 329115 334119
      338119 343120 344113 342106 338100 336095 336091 339084
      345072 349067 353063 358060 361056
 0.25 294809 293808 291807 289807 288808 287808 285807 284808
      285810 286810 288810 289811 291811 293810 294809
 0.50 524195 524192 523191 522189 520189 520191 521193 522194
      523196 524195
 0.50 528912 525900 521889 521882 522874 521865 519858 516855
      513859 508869 503872 499873 491874 488878 486884 485889
      484899 486913 487920 487928 484941 484946 487950 504962
      505960 506956 505950 507944 510941 515942 518941 520934
      521926 526920 528912
 0.50 356053 356048 356042 357031 355025 352022 347015 342007
      335000 331998 325997 315000 307003 300009 298012 300016
      303019 305024 305030 304036 304040 306045 311053 317060
      322067 329074 332075 335073 343067 356055 356053
 0.50 332099 332097 331094 329092 328092 326093 325094 324096
      323097 323098 325100 327102 328102 330102 332101 332099
      332099
 0.50 324805 324803 323803 323801 321800 320800 318801 317802
      316803 316804 315806 314807 313809 314811 315812 317811
      319811 320810 322808 323808 324807 324805
 0.50 314981 314973 313968 308960 301952 299947 298939 294914
      292900 291895 288889 283879 281867 278855 277849 278842
      280836 283833 291827 292825 291822 287820 277815 269808
      266806 263801 263798 262796 259796 252805 250810 249815
      248821 248826 258846 259854 258859 256870 255883 255891
      256899 258905 261908 266915 270925 274937 279947 283956
      283962 281966 276978 274984 275991 277995 280999 290003
      297003 302002 314981
 0.50 279045 279042 279040 278040 277040 275040 274042 274044
      274045 276045 278045 279045
 1.00 513923 513921 512919 511921 512923 512924 513923
 1.00 505906 506901 505897 503898 502901 503903 502901 498898
      495897 495901 497906 500914 498921 497928 499930 500928
      502921 504913 505906
 1.00 351051 351042 350035 348029 346024 338017 333014 327014
      322017 319022 320028 320033 319035 315040 315045 318051
      321055 332062 337063 342061 346058 350053 351051
 1.00 294993 295991 294989 293988 292987 292986 290985 288985
      286986 285987 285989 284991 285993 286995 287995 288996
      289996 291996 293995 294993
 1.00 289933 286920 286915 286908 284901 282895 279890 277884
      274869 271865 267868 266882 267898 268904 271911 277920
      285928 289933
 1.50 348050 348042 347035 344030 339026 334024 330027 328036
      326041 324044 325048 327053 332056 335058 339058 345055
      348050
 2.00 346046 346039 344036 341033 338032 336034 334038 332042
      330047 331051 335054 339054 343052 345048 346046

$$




USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.