Quantitative Precipitation Forecast
Issued by NWS

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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

000
FXUS04 KWBC 210659
QPFPFD

QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
259 AM EDT WED JUN 21 2017


PRELIM DAY 1 QPF DISCUSSION
VALID JUN 21/1200 UTC THRU JUN 22/1200 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR


DAY 1

...GULF COAST AND SOUTHEAST...

HEAVY RAINFALL IS LIKELY TO CONTINUE ALONG PORTIONS OF THE GULF
COAST REGION IN ASSOCIATION WITH TROPICAL STORM CINDY...WITH THE
THREAT SPREADING A BIT FURTHER INLAND AS WELL TODAY OVER PORTIONS
OF MS/AL. A BROAD PLUME OF TROPICAL MOISTURE IS ASSOCIATED WITH
THIS SYSTEM...WITH PWAT VALUES OF 2"+ EXPECTED OVER MUCH OF THE
SOUTHEAST BY THIS AFTERNOON...WITH VALUES AROUND 2.5" PROBABLE AS
WELL. IN FACT RECENT RAP RUNS ARE FORECASTING PWAT VALUES NEAR ALL
TIME RECORD MAXES ACROSS PORTIONS OF LA/MS/AL AND THE FL PANHANDLE
(ALTHOUGH THE FORECAST COULD BE A BIT OVERDONE). NEEDLESS TO SAY
THE ATMOSPHERE WILL BE RIPE FOR EFFICIENT WARM RAIN PROCESSES
CAPABLE OF PRODUCING HEAVY RATES EVEN WITHOUT ROBUST DEEP
CONVECTION. CONTINUES TO LOOK LIKE WE WILL SEE TWO SEPARATE AREAS
OF HEAVY RAINFALL...ONE ASSOCIATED WITH A CONVERGENCE AXIS WELL
NORTHEAST OF THE TROPICAL SYSTEM...AND ANOTHER CLOSER TO (ALTHOUGH
STILL NORTH OF) THE CENTER OF CINDY.

THE HEAVIEST RAINFALL OVER THE DAY 1 PERIOD APPEARS TO LIKELY BE
ASSOCIATED WITH THE CONVERGENCE AXIS AND FEEDER BAND WELL
NORTHEAST OF CINDY. ALREADY SEEING HEAVY RAINFALL IN THIS AREA
MOVING INTO PORTIONS OF SOUTHERN MS/AL AND THE FL PANHANDLE.
SHOULD SEE WAVES OF RAIN CONTINUE THROUGH THE DAY WITH STRONG LOW
LEVEL MOISTURE TRANSPORT PERSISTING. EXPECT THAT WE WILL SEE A
BROAD SHIELD OF STRATIFORM RAIN WITH EMBEDDED LOW TOPPED
CONVECTIVE CORES CAPABLE OF PRODUCING VERY HEAVY RAINFALL RATES.
THE THREAT SHOULD SLOWLY PROGRESS A BIT FURTHER INLAND THROUGH THE
DAY AS WELL...ALTHOUGH WOULD EXPECT THE INTENSITY TO GRADUALLY
WANE THE FURTHER NORTH YOU GO. AS CINDY PROGRESSES WEST THIS
MOISTURE TRANSPORT AXIS MAY TEND TO SLOWLY SHIFT WEST AS
WELL...WITH CONVECTION EVENTUALLY PROPAGATING A BIT BACK TOWARDS
THE NORTHEAST LATER IN THE DAY. SOME MODEL DIFFERENCES CONTINUE
WITH THE EXACT PLACEMENT OF THIS HEAVY RAINFALL AXIS AND ITS
INLAND EXTENT. STAYED AWAY FROM THE 12Z ECMWF...WHICH APPEARED TO
BE TAKING CINDY TOO FAR WEST AND THUS ALSO WAS WEST WITH THE HEAVY
RAINFALL. OF THE GLOBAL GUIDANCE THE 0Z GFS AND UKMET SEEMED TO
BEST MATCH OUR EXPECTED EVOLUTION...ALTHOUGH THE GFS WAS PROBABLY
TOO FAR INLAND WITH THE HIGHEST TOTALS...AND THINK THE UKMET IS
PROBABLY KEEPING THE HIGHEST TOTALS TOO CONFINED TO THE COAST.
OVERALL THUS QPF FORECAST RELIED HEAVILY ON THE 0Z SUITE OF HIGH
RES MODELS. WPC QPF GENERALLY STAYED CLOSE TO A CONSENSUS OF THE
AVAILABLE HIGH RES GUIDANCE...WHICH ENDS UP CLOSEST TO THE 0Z NSSL
WRF. THE DAY 1 WPC QPF IS CALLING FOR 3"+ FROM SOUTHEAST MS INTO
SOUTHWEST AL AND THE FAR WESTERN FL PANHANDLE...WITH 5-8" IN FAR
SOUTHERN AL AND FAR WESTERN FL PANHANDLE. THIS IS A BIT OF A SHIFT
EAST FROM OUR PREVIOUS FORECAST...AND BRINGS SOME HEAVIER TOTALS
FURTHER INLAND. AMOUNTS OF THIS MAGNITUDE ARE SUPPORTED BY ALL THE
HIGH RES GUIDANCE. AGAIN THE MAIN UNCERTAINTY IS NOT REALLY WITH
THE GENERAL MAGNITUDE OF AMOUNTS...BUT WITH THE AXIS OF HIGHEST
TOTALS. SOME CHANCE THE AXIS SHIFTS A BIT WEST OR EAST OF OUR
CURRENT FORECAST...WITH OUR CURRENT FORECAST FEATURING A PLACEMENT
IN THE MIDDLE OF AVAILABLE GUIDANCE.

THE SECOND AREA OF HEAVIER TOTALS IS FORECAST ALONG THE SOUTHERN
LA COAST INTO FAR SOUTHEAST TX TO THE NORTH OF CINDY`S
CIRCULATION. STILL SOME UNCERTAINTY WITH THE SPEED AND TRACK OF
CINDY WHICH WILL IMPACT THIS RAINFALL AXIS...WITH WPC FOLLOWING A
CONSENSUS...WHICH MATCHES WELL WITH THE OFFICIAL NHC TRACK. ONLY
REALLY LEANED AWAY FROM THE 12Z ECMWF (TOO FAR WEST) AND THE 0Z
HRW ARW (TOO FAR EAST)...OTHERWISE A BLEND OF THE GFS/UKMET AND
THE HIGH RES GUIDANCE WAS USED. LOOKING AT AMOUNTS UPWARDS OF 2-4"
THOUGH 12Z THURSDAY..WITH LOCALIZED AMOUNTS APPROACHING 6"
POSSIBLE.


...PLAINS INTO THE MS VALLEY AND GREAT LAKES...

LIKELY TO HAVE CONVECTION BREAK OUT TODAY ALONG THE DRY LINE FROM
THE TX PANHANDLE INTO THE CENTRAL PLAINS...WITH ADDITIONAL
CONVECTION ALONG/NORTH OF A WARM FRONT OVER THE MS VALLEY AND
GREAT LAKES AS LOW LEVEL MOISTURE TRANSPORT INCREASES INTO THIS
BOUNDARY. WPC QPF FOLLOWED CLOSE TO A BLEND OF THE HIGH RES
GUIDANCE ACROSS THESE REGIONS.


CHENARD

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


24HR QP VT 22/12Z
 0.01 559110 551109 546107 542103 537095 532085 529071 525062
      518054 513046 509037 504029 498023 492017 486012 483009
      480005 476001 468002 464999 462994 460990 459984 457988
      457004 456018 454030 451036 447041 444043 441041 440036
      439029 438024 437018 434006 433001 435996 439987 439980
      435973 432973 430978 430984 428987 422994 418997 412999
      405003 399012 392019 389022 387027 386034 387039 393049
      397056 396062 393064 386058 383049 382041 380040 378043
      378048 377060 373066 369064 366059 365053 364051 360050
      351053 344057 342058 341061 340063 337063 327059 319054
      322052 327050 330049 333045 340042 349042 353043 356042
      356038 353036 344038 335034 337023 338018 341013 346012
      350007 365998 374992 382989 391984 394981 396976 399964
      403956 412942 409938 407933 409926 410921 410915 412912
      415911 417906 418898 418891 423892 424890 424886 423882
      423878 421873 415862 411852 407843 406839 404837 402841
      400850 399857 398862 397871 395880 393888 390892 387892
      385890 383885 383878 383871 384865 385852 386844 387838
      389828 390814 390799 392787 391779 384780 376783 373779
      371774 366781 363784 362788 361797 364798 365800 366806
      364809 361817 359821 360827 367851 368857 371861 375869
      374898 372910 368919 365927 361934 358938 355939 346939
      340939 337941 331946 319959 312966 304972 300973 296972
      288967 280960 270958 261954 255948 250940 247932 247920
      248911 251889 252881 254875 258865 260860 263855 266853
      271852 278851 282849 289843 293839 289835 285832 281830
      273827 269825 266823 258820 252815 247807 245802 247799
      249797 254797 262798 268800 275802 280805 291809
 0.01 291809 300810 306812 315809 318801 323767 325757 328750
      331741 330735 331729 335728 342729 348725 352719 357711
      361704 362699 364699 370705 375712 378718 381726 381736
      380748 378757 377760 381759 385758 389755 389744 391737
      393729 395722 402706 407699 412698 417699 419701 423700
      425703 426706 426715 424725 422736 421746 421757 419769
      417785 415794 415800 414805 414812 413817 414820 416820
      419818 428814 434817 443827 451840 456849 461855 464858
      469857 476851 478849 482849 488848 502854 516860 522863
      526865 528870 535882 542898 547908 550918 552928 552945
      552958 555966 561982 564985 565989 566998 568013
 0.01 525256 522256 520256 517257 515257 513259 511260 508262
      507264 507266 507272 508275 510278 511280 513283 516285
 0.01 542197 537191 532189 528187 528181 528175 526166 522158
      522151 522145 519138 516131 512123 508113 506105 504096
      504088 503084 501073 498054 493034 492030 489030 486037
      484049 482061 482073 483082 488102 489106 489113 488124
      490134 491138 491146 494153 498159 494168 494172 497177
      501183 505188 510189 513188 516187 518192 517198 518201
      518207 519210 523216 526217 529216 533217 538213
 0.01 501642 501637 499633 497631 493630 483631 479632 476635
      468638 464642 461646 457653 453660 445670 440684 439693
      438695 440697 442700 442705 440713 439716 439721 442726
      446727 447731 448737 446741 444742 443746 443752 448751
      450753 454752 459753 464753 469751 484728 489711 491695
      494688 495684 498680 500675 501672 500666 498664 498659
      499652 501642
 0.01 385196 384195 383193 383192 381192 380195 381195 382197
      384196 385196
 0.01 338080 338078 336075 333074 329074 327076 325076 323080
      323083 324085 326087 328088 331088 333087 335085 336082
      338080
 0.25 559090 555062 555055 554048 551039 548026 548017 545019
      543023 541024 540021 542014 545012 547012 548010 550003
      550996 548989 546979 544973 544968 541935 537926 533919
      526912 521911 518914 515921 507923 504924 499922 497924
      497926 499932 504937 500944 497949 496954 492969 493976
      494981 499988 505996 513002 518008 524014 527018 530023
      532026 537029 539033 538038 535043 535046 532046 532053
      534058 537071 542078 550082 551087 555091 557092 559090
 0.25 471680 470676 468673 461672 458675 457679 456687 456697
      459707 457711 458715 463713 464710 465706 464702 461691
      463687 466687 469686 471683 471680
 0.25 456884 456876 455870 452860 448849 444842 440839 436839
      433847 431853 431859 429862 424864 426873 428886 429899
      429909 428916 424919 422922 421928 423933 426935 428933
      435930 440929 443924 445915 448904 450894 456884
 0.25 444012 445010 445007 445005 446002 446000 446998 445995
      445994 443994 443995 442997 442000 442002 442005 442007
      442009 442012 442014 444013 444012
 0.25 435957 435952 434949 433946 431944 430945 429942 428938
      426936 423938 423942 424947 426949 428951 430953 431955
      434957 435957
 0.25 421964 420961 417961 414966 412971 408977 405982 402986
      399991 401993 405993 411991 414987 415980 418973 421966
      421964
 0.25 420860 420858 420856 420853 420851 420849 420846 419844
      419842 418840 417839 416838 414840 415842 415844 415847
      416849 416851 416854 417855 417856 417858 418860 419861
      420860
 0.25 386004 385001 382001 378004 374006 371006 369007 365011
      361012 354018 347019 344019 343022 347026 352028 357027
      361023 364019 368016 375019 382020 381015 379010 383007
      386004
 0.25 373751 373744 371736 368732 365730 361729 356731 351739
      343753 339760 334767 330771 329777 327788 322810 316815
      309818 291813 278814 273814 270811 263805 260805 258808
      259812 265817 270820 275823 278825 287826 293826 297828
      304823 307823 311826 317833 317838 314842 311844 306845
      296847 292851 283858 277863 270869 264877 262885 260894
      260906 261915 261922 262929 266938 272945 279951 291960
      295963 299962 305957 315954 322949 323943 322938 327929
      330921 330916 326916 323917 320916 322912 328912 333910
      336906 338902 342899 346897 351897 356896 359893 361891
      365889 369888 369884 365882 361881 358870 356865 356857
      356844 357832 351826 349830 346831 340828 333825 329823
      328818 329813 331807 335798 336794 339790 345781 350774
      353770 355769 357770 362775 365776 366773 373751
 0.25 351848 351846 351844 350842 350841 350842 349844 349846
      349848 351850 351848
 0.25 315824 315822 314821 313820 312820 310820 312822 314824
      315824
 0.50 539973 540968 539966 537960 535953 532949 528946 525949
      520959 512963 508967 507973 512983 518991 523994 525994
      524988 529989 534986 536979 539973
 0.50 449879 450875 450870 449862 448856 446850 444848 442849
      439854 435864 433868 431873 432883 431890 433897 433904
      433909 434912 436913 443904 444898 445892 447885 449880
      449879
 0.50 357881 356874 354872 347867 345859 342853 337845 331840
      329839 325840 321845 304851 297853 291856 284861 279867
      275872 272878 270887 271897 274915 272924 272930 274935
      277941 281945 293957 295958 299957 305954 311951 317945
      319936 321930 321924 319921 313916 313912 315909 318903
      322901 327902 332900 336898 345890 352886 357881
 0.50 324818 324816 323814 321814 320815 319815 317816 316817
      317819 318820 319821 321821 323820 324818
 0.50 300819 299817 295817 290816 290820 283819 277819 272817
      274821 279823 285823 292824 298824 300819
 1.00 340882 340876 339872 334867 326866 322862 320858 317856
      309854 304855 299856 294860 284869 282872 281876 281884
      287900 291901 296900 302902 310903 315900 323897 329894
      335889 339884 340882
 1.00 314939 315931 314926 311920 308916 304913 302909 293906
      290904 286905 284908 280919 278924 277931 283940 290947
      294951 297952 307949 312946 314941 314939
 1.50 335882 335878 334873 330870 321865 313858 307856 302857
      297861 293865 286873 286877 287881 289887 295896 306901
      318896 324894 327891 332887 335882
 1.50 312939 313932 311928 307920 301914 297912 293911 290913
      287916 282923 281929 283935 284939 287941 295945 298948
      303948 308947 311945 312939
 2.00 333880 333876 331873 326870 322868 317864 314860 309858
      305857 302859 299862 291870 288876 289881 292887 296891
      300895 304898 308898 311897 317895 322892 325889 330884
      333880
 2.00 310935 308928 304922 303918 299916 294914 288918 284924
      284928 285931 285936 287939 294942 301944 303945 307944
      310937 310935
 3.00 327878 326874 323871 316866 310861 306860 303863 297869
      292875 292881 294884 300890 303893 307894 316891 320888
      322885 327878
 3.00 299931 300926 299924 297921 295922 294925 292929 291931
      290933 290937 292938 294937 297935 299933 299931
 4.00 322879 323876 321873 319871 314867 310866 308863 304866
      299871 294876 298884 302889 305891 308890 314887 320881
      322879
 5.00 319877 317873 315870 311869 307867 304868 301872 299874
      298878 299882 302886 305888 311887 314884 316881 319877
      319877
 6.00 317877 316874 314872 311871 308869 305870 303872 301875
      300878 301881 303884 305885 309884 311883 313881 315879
      317877
 7.00 313877 313875 312874 310873 308872 306872 305872 303874
      303875 303876 302878 303880 305881 307881 309880 310879
      312878 313877

$$





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