FXUS04 KWBC 162217
QPFPFD
 
QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
516 PM EST THU JAN 16 2003
 
FINAL DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION
VALID JAN 18/0000 UTC THRU JAN 20/0000 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR
 

DAY 1...

...ERN U.S...

UPDATE BASED ON 18Z DATA....

THE 18Z ETA HAS COME IN CONSIDERABLY WETTER THAN ITS PREVIOUS
RUN OVER THE MD...DE AND SRN NJ.  THE 18Z GFS HAS BEEN FAIRLY
CONSISTENT BUT IF ANYTHING HAS EDGED THE NRN EDGE OF THE BND
SWD.  BOTH MODELS FCST A SIMILAR TRACK OF THE SFC AND 850 CIRC
CENTERS MAKING IT A TOUGH CALL TO SAY WHICH MODEL IS CORRECT. 
HOWEVER....I NOW STRONGLY PREFER THE ETA DESPITE ITS BEING THE
LESS CONSISTENT MODEL OF LATE.  RADAR IMAGERY SHOWS AN AREA OF
IMPRESSIVE ECHOES ACROSS ERN KY THAT STILL IS SHIFTING AND
FORMING TO THE ENE.  THE VISIBLE SATELLITE IMAGERY SHOWED
LUMPINESS ACROSS THIS SAME AREA SUGGESTING POCKETS OF HVIER
SNOW IS EMBEDDED IN THIS EXPANDING AREA OF ECHOES. 
MEANWHILE...SATELLITE IMAGERY SHOWS NO SIGNS THAT THE SRN
IMPULSE IS BEING DAMPED BUT INSTEAD INDICATES THAT IT IS LIFTING
ENEWD SO THAT STRONG VERTICAL MOTION ASSOCIATED WITH THE TN
AND KY ENHANCED ECHOES AND MDT TO HVY SNOW SHOULD SHIFT
ACROSS VA INTO MDT WITH THE NRN EDGE OF THE HVIER AMNTS NOW
LOOKING LIKE IT WILL INCLUDE DCA AND BWI.  I AM NOW FCSTING .25
INCH
OR GREATER LIQUID EQUIVALENT AMNTS INTO DC AND BALTIMORE.  THE
COLD TEMPS AND STRONG UVV FCST BY THE ETA AND SUPPORTED BY THE
RADAR AND SATELLITE IMAGERY SUGGESTS THE POTENTIAL FOR HIGH
SNOW TO LIQUID RATIOS ARGUING THAT THERE WILL BE ENOUGH PCPN TO
SUPPORT 3 TO 5 INCH AMNTS ACROSS THE CITIES AND HVIER AMNTS TO
THEIR SOUTH AND EAST.  PLEASE SEE THE LATEST CCCQPFHSD
DISCUSSION AS WELL THE ASOCTD GRAPHICS FOR FURTHER DETAILS.

OTHER THAN THE ABOVE SYSTEM...A VERY DRY WEATHER PATTERN WILL
BE IN PLACE FOR THE REMAINDER OF THE NATION.    SOME VRY LGT
SNOWS ARE LIKELY FM THE GTLKS NEWD THRU WRN NY STATE AND WRN
NEW ENG..ASOCTD WITH ONE H5 SHRTWV TROF DROPPING SEWD INTO
THIS AREA.    VERY LGT SNOWS ARE ALSO LIKELY OVR THE NRN ROCKIES
AND NRN HI PLAINS ASOCTD WITH ANOTHER SHRTWV DROPPING SEWD ON
THE E SIDE OF THE STRONG WRN NOAM LONGWV RIDGE.



DAY 2...

LK EFFECT SNOW IS EXPECTED TO START DURING THE LATTER HALF OF
THE PD AS A CLIPPER SYS SWINGS THRU THE REGION. THE SFC/H8 FLOW
WL NOT BE THAT STRONG AND PWS WL BE AOB 0.25 INCH. MANUAL QPFS
STAYED CLOSE TO 0.10 INCH IN THE UP OF MI. OTHERWISE...NO
HYDROLOGICALLY SIG PCPN IS EXPECTED OVR THE LWR 48 THIS PD.


DAY 3...

ANOTHER CLIPPER WL SLIDE DOWN THE E SIDE OF THE ROCKIES. THE 0.50
PWS EXCEED THE 70 PCT SATURATION THICKNESS CRITERIA IN THE LEE OF
THE ROCKIES...SO KEPT CLOSE TO THE GFS. BETWEEN DAYS 2 AND 3...
THE
HIGHEST AMTS EXPECTED WL BE CLOSE TO 0.25 INCH LIQUID EQUIVALENT
TO THE LEE OF LK SUPERIOR IN THE UP OF MI. ACRS THE GRTLKS...ONLY
LGT WAA SNOWS ARE EXPECTED W/THE FIRST CLIPPER SYS MOVG THRU
THE SCENE. NO HYDROLOGICALLY SIG PCPN IS ANTICIPATED ACRS THE
LWR 48 ON DAY 3.


KORTY/ROTH

GRAPHICS AVAILABLE ON THE WEB AT http://www.hpc.ncep.noaa.gov
24HR QP VT 18/00Z
 0.01 542845 540828 539819 538815 535814 531827 529833 528841
518890 
      516900 513913 509923 506934 502944 497954 492963 485971
480979 
      473985 468994 467000 465004 465012 463016 463030 469039
474040 
      476040 479038 497041 514049 519042 523033 528005 538952
540938 
      541923 542908 542901 540892 542887 541881 541874 542867
542845 
 0.01 523262 515253 512242 511236 506231 501229 499232 499237
500241 
      502247 503252 502257 499255 495250 492248 489247 487255
489261 
      490266 494272 498279 506288 509289 515286 
 0.01 535220 538211 538201 535195 532192 529188 526183 521181
517181 
      516190 517195 519202 521209 523215 526219 531221 535220 
 0.01 458634 448626 446622 443621 437623 428637 422643 417651
412656 
      407663 398670 395669 391671 383677 377683 371690 364696
360700 
      354706 345716 335729 328739 321752 315765 309777 301789
297793 
      294796 290797 284797 281798 277800 265808 258816 256822
257827 
      259829 269833 268848 269853 272856 277853 282848 288845
296842 
      297844 291855 288869 288875 290885 291888 293890 298889
304886 
      312881 318876 322871 331861 334863 336866 337871 338875
341879 
      344882 350885 353886 357885 362882 367878 375864 385852
390845 
      393838 395833 399826 402819 406815 408818 409823 411827
415828 
      418826 421822 423819 425817 428819 432826 438831 442835
445841 
      444845 441851 437855 433856 426856 421857 416859 412863
410867 
      410870 413875 418877 449870 455871 458874 460877 465899
466901 
      468899 473889 475884 475881 476874 475867 473857 478857
480854 
      480849 480844 476839 468835 465835 464840 462835 462830
461820 
      457799 459789 462781 464770 465759 466744 466725 468709
469704 
      468699 466695 462696 457699 455695 451698 447704 444708
443714 
      443718 440722 435728 439730 441734 438737 429750 425754
420745 
      415739 414733 414730 417723 421716 425711 429704 437690
447674 
      453665 454658 458634 
 0.01 488139 487133 485130 479124 473123 466124 464118 463114
467113 
      470110 467106 464105 460104 458101 454093 452091 447090
438091 
      433095 431097 432100 435108 438112 440115 446120 452123
455126 
      455130 455136 457141 461142 465143 474142 478144 482144
485143 
      488139 
 0.01 447774 446772 444774 442777 442778 440782 440783 439787
439789 
      438792 439796 441796 441795 442791 443789 444786 445784
446781 
      446779 447775 447774 
 0.01 451080 451076 450075 448072 447072 444069 441070 439072
441074 
      444076 444077 447079 449080 450081 451080 
 0.01 448043 447041 446039 444037 441038 440040 440044 441046
443048 
      444048 445048 447045 448043 
 0.01 416076 416068 417064 416060 412058 407057 404055 398056
395058 
      392062 392066 398066 398068 396076 398078 401078 404076
407077 
      412077 416076 
 0.25 415698 414694 411696 407700 402701 397698 390701 383706
372715 
      366721 359724 352729 348734 340745 337751 335758 335765
336768 
      341773 346776 356779 362782 362787 357798 359800 362799
367796 
      377786 383780 386774 390769 392763 397748 402737 405730
406726 
      406721 408716 412709 415698 
 0.50 398731 398723 394717 389717 384720 379724 375729 370736
369741 
      370748 373760 371763 372770 376772 380772 385767 387764
391756 
      395745 398735 398731  
 
24HR QP VT 19/00Z
 0.01 541117 540097 538092 535085 535074 533068 532062 529057
525053 
      520049 511041 496031 496017 498002 498992 500986 499976
499967 
      501962 500953 500949 501945 501935 499918 500909 502903
504891 
      505883 504875 501856 499850 496843 484821 483812 481801
479792 
      478788 475784 454823 452827 448831 443834 437837 427839
418839 
      398838 388839 379840 372841 367844 359849 351855 343864
340873 
      341885 343892 345895 347899 347903 343906 338913 332923
329931 
      325938 323949 322953 324957 328958 334957 345955 364948
370947 
      376951 383955 385955 387958 392959 396962 400963 409968
413969 
      417972 422972 425975 434981 450991 457999 463008 469021
462030 
      459036 458041 459046 461052 467060 472063 475068 502102
509111 
      515122 520133 523139 527142 530141 532138 536130 541117 
 0.01 426699 425695 422693 421693 419694 416696 414697 411700
411701 
      412704 413705 417705 417705 420706 423705 425702 426699 
 0.01 440761 439760 436759 433761 432765 432767 432769 433773
435776 
      437772 437771 438767 439766 440762 440761 
 0.01 427789 426789 424791 423792 422795 421797 420799 418802
418804 
      417807 417810 416812 416816 418816 419814 420812 422809
422808 
      423804 424803 425799 425797 426794 427792 427789 
 0.01 450080 450078 450076 447073 446072 444070 443072 444075
445076 
      447079 449080 450081 450080 
 0.01 445044 445039 444037 441037 440040 441042 442044 444045
445044 
 0.01 397797 391796 386798 379807 373811 366815 362818 359822
356828 
      354835 352840 351843 353845 358840 360836 362829 366824
368826 
      369831 372836 377825 380821 385816 391806 397797  
 
24HR QP VT 20/00Z
 0.01 551154 549132 550122 550110 549099 547089 542075 536062
527048 
      519037 516028 513016 509001 505986 508981 515980 518978
519974 
      522968 522964 524960 524951 525942 524929 521905 521898
522892 
      520881 516857 514851 512848 511843 506823 504810 505802
512771 
      514765 514762 514754 513745 511741 507739 503737 500739
496739 
      492740 486743 479746 473744 470735 467731 464728 463723
458720 
      453717 447715 435724 430728 424734 417739 414744 410754
406760 
      405767 401778 391787 386791 379796 360816 352825 345833
341836 
      340842 342848 346853 350858 354861 358864 361866 364866
369869 
      375870 381873 384876 390881 393886 396889 399894 406905
410921 
      415937 420952 427966 431970 434977 438983 442989 445002
447006 
      445010 440011 437016 435020 436026 437036 438043 442062
444071 
      445078 447087 447095 427092 429099 426102 422103 423108
427111 
      430111 435113 440117 442124 438132 436138 433148 435159
439165 
      448175 451176 454170 456163 458160 464164 468168 479175
483178 
      489184 500194 510205 520220 523226 526230 531232 533229 
 0.01 522266 519257 517243 514236 508226 503219 497212 492209
488207 
      483206 477206 470208 462212 457217 455220 455224 457226
459227 
      460229 455230 448233 445241 449244 453244 471246 476248
480251 
      487257 493265 497273 502283 509290 511291 
 0.25 534205 534200 534200 531196 530194 529193 526192 525193
525198 
      525198 528203 528203 530205 533207 534205