Quantitative Precipitation Forecast
Issued by NWS

Home | 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 200722
QPFPFD

QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
321 AM EDT THU APR 20 2017


PRELIM DAY 1 QPF DISCUSSION
VALID APR 20/1200 UTC THRU APR 21/1200 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR


DAY 1...

...CENTRAL-EASTERN OKLAHOMA EASTWARD INTO SOUTHERN MISSOURI AND
NORTHERN ARKANSAS...

THE INITIAL SHORTWAVE PROGRESSING SLOWLY ENE ACROSS THE UPPER MS
VALLEY TODAY...ALONG WITH THE PRE-FRONTAL CONVECTION AND ATTENDANT
OUTFLOW BOUNDARIES...WILL ALLOW THE SURFACE FRONT TO DROP INTO
SOUTHERN OK-CENTRAL AR BY LATE IN THE DAY. THIS BOUNDARY WILL BE
THE FOCUS FOR POTENTIALLY HEAVY RAINFALL FROM DURING DAY 1...AS A
VIGOROUS NW-SE ORIENTED UPPER LEVEL JET STREAK DROPS INTO THE 4
CORNERS REGION AND AMPLIFIES THE UPPER TROUGH OVER THE
CENTRAL-SOUTHERN ROCKIES. THE DEVELOPING LEE-SIDE LOW AND
DOWNSTREAM UPPER DIFLUENCE...ALONG WITH CONTINUED FORCING WITHIN
THE RIGHT-ENTRANCE REGION OF THE UPPER JET STREAK DRAPED OVER THE
CENTRAL PLAINS...WILL MAKE FOR A DYNAMICALLY-FAVORED ENVIRONMENT
(STRENGTHENING UPPER DIVERGENCE AND LOWER LEVEL FGEN ALONG THE
STATIONARY BOUNDARY) ACROSS CENTRAL-EASTERN OK E-ENE INTO SOUTHERN
MO AND NORTHERN AR. MEANWHILE... A POOL OF ANOMALOUS MOISTURE (PW
AND 850-700 MB MOISTURE FLUX STANDARDIZED ANOMALIES AROUND +2 PER
THE SREF AND GEFS) ADVECTING ACROSS THE STATIONARY
BOUNDARY...ALONG WITH MODEST DEEP-LAYER INSTABILITY (MUCAPES
1000-1500 J/KG)...WILL PROVIDE A FAVORABLE THERMODYNAMIC
ENVIRONMENT FOR AREAS OF HEAVY RAINFALL ACROSS THE
REGION...PARTICULARLY OVERNIGHT. FURTHERMORE... WHILE NOT OVERLY
ROBUST...THE STRENGTHENING LOW-LEVEL WSW FLOW AHEAD OF THE FRONT
WILL BECOME MORE PARALLEL AND CLOSE TO THE MAGNITUDE OF THE MEAN
850-300 MB FLOW BETWEEN 00-12Z...ENHANCING THE POTENTIAL FOR
UPWIND PROPAGATION AND THUS CELL TRAINING. AS A RESULT...WPC WILL
CONTINUE TO CARRY A SLIGHT RISK OF EXCESSIVE RAINFALL INHERITED
FROM THE PREVIOUS DAY 2 OUTLOOK... THOUGH BASED ON THE LATEST
GUIDANCE TRENDS (PARTICULARLY WITH THE ENSEMBLE OF HIGH-RES
WINDOWS)...HAVE SHIFTED THE OUTLOOK SLIGHTLY ENE. IN TERMS OF THE
QPF...WPC UTILIZED A MULTI-MODEL BLEND...LED BY THE HIGH-RES MEANS
ALONG WITH THE WPC BIAS-CORRECTED ENSEMBLE MEAN...WHICH YIELDED A
STRIP OF 1-1.5" AREAL-AVERAGE TOTALS ACROSS THIS AREA. BASED ON
THE AFOREMENTIONED FAVORABLE DYNAMICAL AND THERMODYNAMICAL
PARAMETERS...SOME OF THE HIGHER LOCALIZED AMOUNTS (2-3+ INCHES)
ARE REFLECTED ACCORDINGLY. HAVE ALSO DELINEATED THE SLIGHT RISK
AREA TO WHERE THE (LOWER) FFG VALUES AND (HIGHER) NATIONAL WATER
MODEL SOIL SATURATION OUTPUT WOULD BE MORE CONDUCIVE TO LOCALIZED
RUNOFF ISSUES.


...OHIO VALLEY / GREAT LAKES / NORTHEAST...

THE AFOREMENTIONED COMPACT NORTHERN STREAM SHORTWAVE TRAVERSING
THE UPPER MS VALLEY-GREAT LAKES DURING DAY 1 WILL PROVIDE AN
EXTENSIVE SWATH OF MODERATE WAA PCPN WITH EMBEDDED HEAVIER AMOUNTS
WITHIN AREAS OF CONVECTION. PER A MULTI-MODEL BLEND...AN AREA OF
1-1.25" AMOUNTS WAS NOTED ACROSS MUCH OF WESTERN AND UPSTATE
NY...ALONG WITH NORTHWEST PA AND SOUTHEAST LOWER MI. DESPITE THE
ANOMALOUS MOISTURE AVAILABILITY AND VIGOROUS DEEP-LAYER DYNAMICAL
FORCING...INSTABILITY BECOMES MORE LIMITED N-NE OF THE OH VALLEY
(MUCAPES DROP TO UNDER 500 J/KG). THIS WILL IN-TURN MITIGATE
SHORT-TERM RAINFALL RATES...HOWEVER...GIVEN THE LOWER FFG
VALUES/ANTECEDENT WET SOILS OVER THESE AREAS...WILL MAINTAIN A
RELATIVELY SMALL "SLIGHT" RISK FOR EXCESSIVE RAINFALL OVER
PORTIONS OF NY...PARTICULARLY THE CATSKILLS WHERE THE FFG IS
LOWEST.

HURLEY


GRAPHICS AVAILABLE ON THE WEB AT
WWW.WPC.NCEP.NOAA.GOV/QPF/QPF2.SHTML

24HR QP VT 21/12Z
 0.01 536207 534198 532185 533171 532165 530159 524152 519151
      516148 512146 507143 502136 499132 497127 495115 494110
      494103 492099 490099 483100 478097 474094 470089 463082
      460074 451057 442039 437030 435026 432021 428014 425011
      422008 418006 415005 409005 405007 396008 392008 389004
      385993 384987 384977 384961 385953 387949 403914 410896
      412891 415887 421882 428877 432878 437879 440882 442888
      444897 452919 456931 458937 458947 458961 464967 469962
      475953 478951 479957 484965 485972 484978 486981 484983
      478984 475980 467974 464972 461971 459973 457979 457986
      461987 465991 467998 470001 473004 482008 485010 490011
      499011 508009 515004 518000 518995 518990 515985 511983
      506982 497982 495981 494978 494970 493963 492955 486949
      478950 482938 484934 487927 490917 492912 492906 495882
      497867 500858 501851 502846 502831 500814 499799 496789
      492775 487752 483740 481733 479729 466711 463700 462691
      460689 460685 460681 462679 468677 471674 475672 479668
      482665 482658 481654 477650 471647 462645 454644 441649
      433657 427664 423667 420668 418666 402666 392669 386674
      379680 373689 368708 366712 363715 358721 351727 343734
      335737 327736 323736 320738 324741 325746 323759 320767
      319779 315786 312796 316799 320796 340768 351752 362738
      375726 379723 381722 382725 385722 390721 394729 396733
      395737 393748 393751 391752 386751 383750 381752 378755
      373764 368772 365779 363782 364789 364792 362794 359799
      357803 354812 351823 346835 341843 334849 331852 331856
      335858 340856
 0.01 340856 349852 353848 355847 355851 351862 346871 343875
      340881 336891 335898 335905 335913 337921 342946 342955
      340960 336971 333984 331989 331997 333004 337006 340007
      341010 341017 344030 349040 352045 353052 356056 361057
      367056 369057 368059 363062 360065 364068 369070 373074
      375081 377083 379083 383083 384090 385093 387093 389090
      391090 391098 386107 386113 383121 384126 388127 392124
      397124 401127 403131 404133 407135 411137 413139 413142
      409146 406150 405158 408163 406168 405175 407183 409189
      408199 405204 399203 393201 388199 385200 387204 391208
      396211 399211 402214 405214 415211 429197 431194 432186
      432181 435180 437187 438194 441198 443204 449205 453202
      458200 466195 468193 471193 478196 481201 480204 478205
      458210 450213 439215 435217 428218 424219 422219 421221
      416232 411242 411245 413246 419248 426250 433252 453252
      460253 464253 476256 482258 488262 492265 496270 501277
      505281 508278 507274 509273 510276 514275 516271 519264
      519257 518249 516237 503218 502213 505211 509210 516213
      522217 525219 530218 534217 535212 536207
 0.01 388769 388767 387766 385767 385768 384770 385770 387770
      388769
 0.01 328906 326900 320895 313894 304895 299898 297901 296906
      290909 282911 274911 269912 266915 271921 276925 282929
      288931 293932 295935 301939 304940 308939 314935 318930
      322924 325917 327909 328906
 0.01 308863 308861 306859 306856 306854 306852 305850 304848
      303848 301848 300849 300851 300853 301855 301857 302858
      303859 304861 306861 308863 308863
 0.01 267821 263815 258811 255809 257805 256801 252801 248802
      246805 244812 242819 243823 245826 252823 258826 262826
      265824 267821
 0.25 516187 516182 514179 507174 491165 485161 480155 474148
      472143 475141 482139 490143 495143 494140 489136 484130
      478126 478117 477112 476107 471104 457101 453093 447087
      447077 446071 443069 438067 433067 430069 427069 427065
      427059 426055 422048 412035 410032 406029 398026 393027
      391031 385036 383040 382045 376049 374052 376054 384057
      387060 388065 388071 388076 390081 396082 401082 405081
      410076 417072 425071 428079 429083 426086 426091 428094
      432103 429106 424108 418112 414111 412108 410099 406098
      406102 405109 403113 403118 405121 414125 419132 419137
      421138 429135 435131 435127 434123 431119 431116 434116
      439117 441119 443123 442127 440131 439134 441137 446142
      445146 442149 440149 441154 443157 444162 454191 463178
      465173 468171 472172 475174 482178 490180 496184 503191
      507193 510192 514190 516187
 0.25 493222 492216 486213 479211 474212 469215 464218 454218
      444223 448226 452232 455237 458236 455233 459230 465226
      469222 472220 479222 486224 491224 493222
 0.25 482239 482237 482234 482232 481230 480229 478229 477229
      475230 473231 471233 471234 470236 472238 473239 475240
      476241 478243 480243 481242 482240 482239
 0.25 492830 492825 490818 489807 490799 489792 485781 480771
      475763 470756 467752 465745 461734 454728 447721 446718
      447713 450704 448702 443702 439704 435708 432713 430718
      425726 422730 420735 418738 413740 410743 408747 404758
      402769 399777 395789 388794 382801 376809 374818 377822
      383823 390824 381842 365877 360885 356893 354898 354905
      352919 352930 350943 347954 346964 343976 342981 343985
      350993 353994 357991 362984 366974 370965 375957 379949
      383939 387929 387921 386913 385904 388893 393883 398876
      404870 410863 417858 421860 426861 436860 443855 447852
      451854 456861 458873 459888 459897 461903 464915 466920
      469923 472925 477924 479921 482915 484905 487892 487876
      490849 492840 492830
 0.25 364728 365726 364724 362724 360726 359727 358727 357729
      356730 355730 354732 353733 353735 354735 355735 356734
      358733 359733 361732 362731 363730 364728 364728
 0.25 335758 336754 333752 332752 329755 329757 328759 327763
      326766 327769 329768 332765 333763 335760 335758
 0.25 309922 310920 310918 309916 308914 308913 306912 305911
      304911 302911 301912 300914 300916 301918 301919 302920
      303921 303922 305923 306923 308922 309922
 0.50 477137 477136 476135 474136 475137 477137 477137
 0.50 483847 483836 482827 479818 477816 476820 475828 474833
      472835 465849 464857 463866 463877 464888 466896 468905
      470908 473909 477910 481903 483896 483886 483877 482866
      482857 483847
 0.50 478790 474781 470775 466772 462772 459774 457771 453761
      452757 456754 457751 458744 457737 453733 447731 442725
      437723 433724 428726 427731 431733 429737 426740 421747
      419751 418757 418760 420763 420766 417765 414763 410765
      409769 408775 408781 409801 408812 411817 414819 410827
      406834 405839 409838 412837 417836 421836 424840 429846
      430852 432855 436854 439851 445845 447843 451844 454846
      459844 457832 456826 457822 462820 464816 464809 463802
      461788 470792 475793 478792 478790
 0.50 469152 469149 468147 464145 461145 459146 457148 456152
      455155 454159 454162 457163 459162 461161 464159 467157
      468155 469152
 0.50 461131 459129 458128 457128 456127 455127 454129 454130
      455132 457133 459134 459133 461131 461131
 0.50 461783 461780 460778 460776 459778 459780 460783 460785
      461783
 0.50 443099 444096 443094 443093 442092 440091 438090 437089
      435089 433089 432090 432092 433093 434094 435095 436096
      438097 439098 440098 441099 443099 443099
 0.50 441108 440107 439107 437107 438110 440110 441108
 0.50 417118 417117 415117 413117 413118 415119 417119 417118
 0.50 415050 414045 412041 408038 405036 401035 398036 396041
      397048 397054 398059 402062 406061 409057 412054 415052
      415050
 0.50 404845 405843 404841 402842 401843 400845 400846 400848
      402847 404846 404845
 0.50 398853 380865 375868 371873 365886 362892 360898 359908
      357915 356924 355933 354942 352948 345980 349982 355979
      360974 362969 366963 370958 372955 373950 376945 379939
      381932 382923 382920 380917 378916 378910 380903 380889
      379885 376884 380883 384877 387871 393862 398853
 0.50 385806 386804 385803 383804 382807 384809 385807 385806
 1.00 476880 476879 475877 474876 473876 472878 471880 471883
      471884 471885 473886 474885 475884 476882 476881 476880
 1.00 451804 450799 448797 442793 439794 437796 434806 434816
      434826 437826 438830 439835 443834 445832 446826 446822
      447818 449809 451804
 1.00 442769 441762 439758 437754 435749 434743 430745 429750
      428755 428762 430766 433770 435774 439776 441772 442769
 1.00 428788 428786 426784 424785 422787 421789 421790 420792
      420794 420797 422798 422799 423799 424798 425798 427796
      427793 428791 428790 428788
 1.00 373914 373908 369907 364914 362917 361923 361929 360934
      358945 355954 355960 358961 363954 367945 369934 370923
      373914

$$





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