FXUS04 KWBC 222227 PAA QPFPFD QUANTITATIVE PRECIPITATION FORECAST DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 626 PM EDT WED OCT 22 2003 FINAL DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION VALID OCT 24/0000 UTC THRU OCT 26/0000 UTC REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR UPDATE FOR 1800 UTC ETA AND GFS.... ...DAY 1... CNTRL TO NRN NEW ENGLAND.... 1800 UTC ETA IS TRENDING SLIGHTLY STRONGER WITH THE DEEPENING MID LEVEL LOW EXPECTED TO MOVE SLOWLY ACRS ERN NY AND INTO WRN NEW ENGLAND TONIGHT AND THEN CONTINUING ENEWD ALONG THE ME COAST DURG THU. AT THE SFC...MAIN LOW WL CONT TO DEEPEN TO THE SOUTH OF NOVA SCOTIA TONIGHT AND THEN MOVE NWD ACRS NOVA SCOTIA THU AND INTO THE GULF OF ST LAWR. WHILE SFC LOW REMAINS WELL EAST OF NEW ENGLAND... LATEST RADAR IMAGERY IS SHOWING SOME ENHANCEMENT IN WHAT MAY BE A DEVELOPING COMMA HEAD AHEAD OF THIS MID LEVEL CNTR. CHANGES TO DAY 1 PRELIM QPF WAS TO INCREASE PCPN IN THIS DEVELOPING COMMA HEAD ACRS FAR NWRN MA...ERN VT...CNTRL TO NRN NH AND INTO WRN ME. PTYPE GUIDANCE FROM THE ETA SUGGESTS PCPN WL BE SNOW ACRS MOST OF VT...CNTRL TO NRN NH AND INTO WRN AND NRN ME. WITH QPF TOTALS FOR DAY 1 EXPECTED TO BE IN THE .50-1" RANGE FROM NRN NH NEWD THRU WRN/NRN ME...HEAVY SNOWS ARE POSSIBLE HERE. UPR LAKES SEWD INTO CNTRL APPALACHIANS... BROAD WNWLY MID LEVEL FLOW EXPECTED ACRS THESE AREAS UPSTREAM OF THE AMPLIFYING MID LEVEL CNTR OVR NEW ENGLAND. SET UP IS NOT GREAT FOR LAKE EFFECT SNOWS AS FLOW WILL HAVE SGFNT DIRECTIONAL SHEAR IN RESPONSE TO WEAK SFC WAVE DIVING SEWD THRU THE UPR MS VALLEY AND THEN INTO THE OH VALLEY AND TOWARD THE CNTRL APPALACHIANS ON THU. BASICALLY LIGHT WARM ADVECTION PCPN EXPECTED AHEAD OF THIS WEAK LOW FROM THE U.P. OF MI..SEWD INTO THE L.P...NRN IN..OH..WRN PA...WV...ERN KY..SWRN VA AND WRN NC. NORTHWEST... SFC ANALYSIS LATE THIS AFTERNOON INDICATES FRONTAL BNDRY BEGINNING TO PUSH INLAND INTO THE PAC NW. SLY LOW LEVEL FLOW ALONG THE FRONT SHOULD BECOME MORE WLY TONIGHT AND TURN INCREASINGLY ANTICYCLONIC BY THU. THE INCREASINGLY ANTICYCLONIC FLOW IN THE WAKE OF THIS SFC FRONT SHOULD KEEP PCPN AMTS RELATIVELY LIGHT. SOME MDT TO POSSIBLY LOCALLY HEAVY AMTS IN THE .50"+ RANGE POSSIBLE IN THE FAVORED TERRAIN OF THE OLYMPICS AND WA/NRN OR CASCADES. INLAND ACRS NRN ID AND NWRN MT...AMTS SHOULD BE LIGHTER IN THE .25"+ RANGE ACS THE FAVORED TERRAIN. S FL... BNDRY LAYER CONVERGENCE ALONG THE SFC FRONT EXPECTED TO SINK SWD INTO CNTRL TO S FL THU EXPECTED TO STRENGTHEN 1800-0000 UTC TIME FRAME. WHILE THE ETA SHOWS WELL DEFINED CONVERGENCE...IT HAS NO PCPN. WENT WITH GFS' HEAVIER AMTS...WITH AREAL AVG AMTS GENERALLY LESS THAN .25"...BUT SOME LOCALLY HEAVIER AMTS POSSIBLE. DAY 2... ...UPPER MS AND MO VLYS... AFTER THE S/WV TROF THAT IS CURRENTLY POISED OFF THE COAST OF THE PACIFIC NW MOVES INLAND AND THRU THE NRN INTRMTN RGN AND NRN ROCKIES ON DAY1... IT WILL CONTINUE TO PUSH SEWD WITH TIME BRINGING A WEAK FRONTAL SYSTEM THRU THE NRN PLNS AND INTO THE UPPER MS VLY BY THE END OF THE PERIOD. THE GFS IS LOWERING HEIGHTS A BIT MORE WITH THE TROF OVER THE NRN PLAINS BY THE END OF DAY2 THAN THE ETA. THUS THE GFS IS ALLOWING MORE MOISTURE TO RETURN FROM THE WRN GULF THRU THE LWR MS VLY AND SRN PLNS. THIS MOISTURE WILL FOCUS ALONG AND AHEAD OF THE COLD FRONT AS IT DROPS INTO THE MID-MS VLY. ETA IS DRIER THAN THE GFS APPARENTLY DUE TO BEING LESS AMPLIFIED. UKMET IS ALSO MORE AMPLIFIED AND IS DEVELOPING MORE PCPN. THUS WENT WITH THE WETTER GFS SOLN HERE. GFS IS SHOWING PW'S IN EXCESS OF 1.25 INCHES FOCUSING IN THE VICINITY OF THE BNDRY WITH 30 TO 40 KTS OF LOW LEVEL INFLOW FEEDING THE MSTR INTO THE REGION. ELSEWHERE NO HYDROLOGICALLY SGFNT PCPN IS EXPECTED. DAY3... ...MID-MS VLY... SGFNT MDT TO HVY RAINS EXPECTED OVER THE MID-MS VLY AS S/WV ENERGY DROPPING THRU THE PLNS CONTINUES TO AMPLIFY THE MEAN TROF OVER THE CENTER OF THE NATION. AS ON DAY2.. THE GFS IS DEEPER THAN THE ETA WITH THIS TROF AND IS AGAIN SUPPORTED BY THE UKMET SOLN. AGAIN SUSPECT THAT THE GFS IS CONSIDERABLY WETTER THAN THE ETA DUE TO BETTER MSTR INFLOW. HAVE AGAIN OPTED TO LEAN TOWARDS THE WETTER GFS AND IGNORE THE DRIER ETA. THEREFORE EXPECT A LARGE AREA OF HALF INCH QPF OVER MUCH OF THE MID MS... LWR MO.. AND OH VLYS. ...PAC NW... WITH THE RIDGE OVER THE WEST COAST HIGHLY AMPLIFIED... ALL OF THE S/WV ENERGY AND MSTR WILL BE DIRECTED UP TO THE NORTH INTO BRITISH COLUMBIA ALLOWING WA TO REMAIN DRY FOR ANOTHER DAY. ROTH/ROBSON GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV 24HR QP VT 24/00Z 0.01 427609 424613 418621 413627 409630 405635 402642 402648 408655 412657 418658 424659 431659 433664 431670 427683 424688 421692 418695 411701 403706 399710 395714 384723 375735 373742 372748 374754 379756 385755 392750 400744 414731 422735 424745 421759 422772 430785 438780 438765 437753 444742 459733 500708 516684 508645 496615 463590 437600 434602 0.01 523262 515236 510222 508217 513212 519219 529215 534205 533179 519158 509148 502130 511111 531084 548053 551019 545994 531995 513010 488040 475063 473083 480097 485116 474120 465119 457129 450143 441139 436137 434146 436154 440162 447179 444182 441182 441186 450193 452196 454196 457190 463185 470178 473177 476180 479183 486185 491188 490193 488193 484196 481196 475198 470201 465204 437214 431214 428217 423220 421222 423228 426231 414231 407233 404235 403241 405245 408249 419253 428255 439254 450253 462255 473259 481263 491270 494272 497278 502284 506288 511289 515286 0.01 388846 396852 404861 412870 421874 440883 456892 471899 487905 500901 505886 495870 476859 446838 435827 425802 409786 400783 390788 382797 368807 355816 348827 347834 349843 353842 357835 363825 370827 378835 388846 0.01 488233 485231 484227 483227 480226 477225 475224 477226 480227 482231 482232 485232 488233 488233 0.01 456114 458106 455101 453096 447095 444096 447099 451101 453105 450107 444106 441105 440108 444112 446114 452117 456114 0.01 273796 271792 269790 263789 257789 253793 251799 249806 252815 256819 261820 264819 268817 270814 272807 272800 273796 0.25 478705 501687 507674 505655 492622 479609 464602 436610 423622 419633 418644 423651 432652 445661 449670 447684 440699 431713 430725 438729 449725 478705 0.25 529199 529192 527184 526178 524173 516166 505160 499161 496163 490162 485165 487170 492175 500182 505190 513198 522203 525204 526203 529199 0.25 516267 517262 515254 511241 502219 497209 495206 489205 479205 471210 455215 451217 445219 441220 442224 457223 462227 466224 470222 475220 478221 483223 487224 490226 492230 501247 506261 507264 513269 516267 0.25 501266 499262 497255 495249 492244 490240 487238 484239 481238 480235 479232 476231 473232 470236 470240 474245 480248 482250 488254 493257 496260 498266 501266 0.25 474159 474154 473153 472150 471148 468145 465143 463144 462145 459147 459148 457152 458155 460156 461157 464159 467162 470163 471162 473160 474159 0.50 461611 477617 486630 497659 495678 479695 469702 443718 440714 443703 453690 462678 462664 454654 442649 434643 430636 430627 435619 447612 461611 0.50 523192 523187 521180 518176 513172 509170 504169 501171 501175 503179 506183 511189 514191 520194 523192 0.50 512261 512254 510247 508240 506235 503231 501228 499221 496216 494213 491216 492225 494230 497234 499238 502243 505248 507254 510260 512261 0.50 487219 490216 488213 487210 485209 483208 480208 479209 476210 475211 473214 472215 473215 476216 478217 481218 484219 487219 487219 0.50 469153 468149 468148 465148 464148 464153 467155 469153 1.00 462643 475644 478634 472625 463622 456620 449619 444623 443630 448639 455642 460643 462643 24HR QP VT 25/00Z 0.01 505663 502656 499652 494647 485648 481650 476653 469664 465673 461682 457690 450699 447707 442728 446731 451731 454727 456722 457717 461714 469708 477708 483708 488705 493700 496692 499681 502676 504671 505663 0.01 562989 562981 560976 558961 556945 553930 547909 540882 537873 531862 527853 521844 516838 510833 504830 498828 483824 476824 469824 460826 451831 437843 432848 426855 416869 407882 398894 389907 381922 378927 376935 374948 372973 373985 373998 372008 374022 383030 395018 412000 433977 437975 442971 448967 455964 464963 473968 484985 488992 498004 503009 508017 512026 514031 517035 519040 521043 524055 526059 530062 535060 539058 544052 549042 553030 557016 560002 562989 0.01 525256 521250 517239 515232 514227 511222 501210 499207 495204 489201 484205 482207 479212 489225 491234 485235 483235 481233 478230 474230 472234 472240 475246 479254 481262 483272 486280 496294 500299 506304 0.01 537206 538201 539195 537188 533181 531175 529169 525164 517155 512152 507147 497145 492139 490134 486130 481128 474127 472127 471131 472136 474140 477140 482143 484146 484150 481151 476150 468140 464140 461144 462150 466155 472163 478168 482172 484177 488181 498188 508193 513199 516204 519210 523214 529216 533212 537206 0.01 509082 508077 506074 503074 499077 494081 491084 488088 486094 488100 493101 497099 502095 505091 507086 509082 0.01 444745 444740 442739 439739 436741 432747 430750 427755 426761 425765 424770 425774 425778 429778 432774 435768 436763 437758 437753 442748 444745 0.01 464106 464102 461098 456099 453097 450095 447095 442096 438097 436100 436104 435108 436112 441114 446117 449118 454118 458114 461110 464106 0.01 422805 421803 420802 417801 415803 414805 413808 413809 413813 415814 418813 420810 422805 422805 0.01 454080 454076 453075 451072 450072 447069 446068 444067 441066 439067 438068 437072 439075 440076 441078 444080 447082 450083 453082 454080 0.01 402794 401791 399790 395790 390792 385795 382797 378802 375805 375808 376811 380811 386809 390804 393802 398799 402794 0.01 431064 430063 427060 424058 423060 424064 427066 430065 431064 0.25 549981 550971 549960 547952 545947 539933 535925 528914 521905 514901 508903 507906 505922 505937 506950 508958 512967 519985 525001 532010 538015 542015 545008 547996 549981 0.25 523265 520259 516250 512242 509235 502233 501236 501240 501244 501250 500253 492248 489247 487256 489266 493276 498283 503290 507292 513290 0.25 404963 419949 426935 435919 442903 447892 446884 439880 422888 402909 398917 395925 394934 394947 394953 396960 398964 404963 0.50 518278 519271 519266 518262 514258 511251 508248 506249 505258 504261 502261 496257 493257 492262 494271 499279 503285 507287 511286 513284 518278 0.50 416912 414910 411911 409914 408915 406916 404920 402923 401924 400928 400929 399932 399936 401939 403937 404935 406933 407930 408928 409926 410924 412921 413919 414917 415916 416912 1.00 506278 505275 505272 503269 501266 498269 500272 501275 502277 505279 506278 24HR QP VT 26/00Z 0.01 549788 546772 541754 537739 533725 529711 525703 514690 512688 509689 502692 496695 490697 482700 478704 475707 458719 450727 444736 433749 413774 406784 397795 389809 380822 376830 371837 367844 361850 343871 337877 332881 325879 319876 302861 298858 288859 285863 281870 285901 285911 283917 281924 278930 265947 263950 262954 262960 261963 257969 257973 261974 288976 295976 302973 307971 315970 319973 321981 322987 324989 328990 332988 335984 343977 350979 354979 358977 364975 370971 379962 388952 395941 412917 417908 422901 426893 428888 431887 435878 440873 445869 451863 480846 486846 492849 495854 496864 495874 492888 486907 475940 474948 475958 476964 478967 483971 496981 506989 502014 499025 496032 488046 486052 486055 487057 489059 493060 502059 507058 516055 519053 523049 527043 531035 536018 538008 541994 541988 543982 543976 545968 545959 546947 546934 547922 547870 549860 550857 550850 551830 551821 550814 550805 549788 0.01 535225 538211 539198 538188 536179 534174 531170 526165 517156 511151 504150 499153 495158 494165 494172 497178 501184 505192 508198 510207 510213 509217 503215 499214 496215 493218 492226 492234 495244 495245 492241 489242 487242 485246 483252 483259 483267 492280 499293 503301 505303 507302 512291 516283 518276 522265 534228 535225 0.25 540804 537791 535780 529764 527758 524756 521760 516774 513792 513800 514810 515820 515830 513845 513855 513865 513875 512884 510900 507915 505935 505940 506946 510951 514950 519944 523939 526932 529924 531916 533900 535860 538842 539826 540811 540804 0.25 533215 534205 534198 533190 531184 527180 524177 519173 516172 513175 513185 514192 516198 519204 521209 523216 526221 529222 531219 533215 0.25 516272 518265 518258 515252 511242 509239 505237 504241 504247 504251 504257 500259 497255 494254 493256 492262 494269 499278 502285 505288 507287 510284 511280 516272 0.25 439800 437792 433793 428796 425799 418805 413813 401830 395837 389843 377857 368870 356885 351892 349901 349906 350913 351919 350925 345941 342951 341955 341959 343962 357958 363958 368954 373949 386936 391930 398922 407907 417892 427877 431866 434857 437847 438842 439837 437831 434828 432825 433821 439800 439800 0.25 337898 333896 327898 324901 320905 318908 315911 314917 317920 320919 324915 327911 329908 332906 335902 337898 0.50 531209 531204 531199 529194 529193 526189 525188 523187 520186 520187 520191 520196 521201 522203 523207 524209 526213 528213 529213 531209 0.50 526898 526893 526888 526883 525879 523875 522875 522880 521885 521887 521890 521895 520900 522904 524904 526900 526898 0.50 514271 515267 516262 514258 513256 512253 509250 507254 507259 507263 507264 50926