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