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000 FXUS04 KWBC 040943 QPFPFD QUANTITATIVE PRECIPITATION FORECAST DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 442 AM EST WED FEB 04 2009 FINAL DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION VALID FEB 04/1200 UTC THRU FEB 07/1200 UTC REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR THE 06Z MDL RUNS WERE IN VRY GOOD AGREEMENT WITH THE 00Z RUNS..SO MADE ONLY VRY MINOR CHGS TO THE PRELIM DAY 1 QPF. DAY 1... SIGNIFICANT PCPN WL BE HARD TO COME BY OVR THE COUNTRY THIS PD..WITH GENLY LGT SNOWS XPCD UNDERNEATH DEEP H5 TROF PUSHING THRU THE ERN STATES..AND SOME LGT RAINS SPREADING INTO PTNS OF CA LTR WED NGT IN ADVANCE OF ERN PAC H5 TROF. IN BTWN..STG AND SLOLY PROGRESSIVE WRN U.S. RDG AND DRY NWLY FLO DOWNSTREAM WL KEEP MUCH OF THE RMNDR OF THE NATION DRY. ...ERN STATES... LATEST MDL SOLNS ARE IN VRY GOOD AGREEMENT IN MOVG THE STG H5 TROF THRU THE ERN STATES THIS PD. UNSETTLED WX WL PERSIST UNDER THIS COLD TROF..LEADING TO A COMBO OF MORE ORGANIZED AREAS OF SNOW PTNS OF THE CNTRL APLCHNS..ERN NC AND ERN ME VCNTY OF S/WV TRACK AND SOME CONTD LK ENHANCED SNOWS..MAINLY LEE LKS MI..ERIE AND ONTARIO. DEEPER MSTR HAS BEEN DISPLACED WELL EWD INTO THE ATLC..SO MOST OF THE SNOWFALL AMTS WL BE ON THE LGT SIDE..WITH THE EXCEPTION OF VRY ISOLD LK EFFECT BANDS..AS IN THE ONE THAT HAS PERSISTED OFF OF LK MI INTO NRN IN SINCE YDA. PLS SEE THE QPFHSD FOR DETAILS ON THE SNOWFALL POTNL. ...CA... THERE ARE SOME SLGT MDL QPF DIFFS HERE..WITH THE NAM SLOER TO BRING IN THE MORE SIGNIFICANT RNFL INTO CA THAN THE OTHER MDLS ARE FCSTG. THE ERN PAC TROF IS ALREADY ON THE MOV AS PER RECENT SATL IMAGERY. GIVEN THIS..AND THE FACT THAT THE NAM IS SOMEWHAT OF AN OUTLIER..WL LEAN TWDS THE FASTER MDL SOLNS HERE. SUFFICIENT LRG SCALE LIFT/MID LVL DYNAMICS FM THE APCHG H5 TROF ALG WITH SOME INCREASE IN LOW LVL ONSHORE FLO AHD OF IT SHLD SUPPORT INCREASING RAINS INTO ESP CSTL SXNS OF CA LTR WED EVE/NGT..WITH SOME GTR THAN 0.25 INCH AMTS LIKELY ALG THE CST AS PER GFS..ECMWF HIRES AND CANADIAN GEM QPF SOLNS. DAYS 2 AND 3... ...WEST... A LARGE SRN STREAM CLOSED MID-UPR LOW WILL SLIDE FROM THE ERN PAC INTO CA LATE WED INTO THURS AND AN UPPER TROUGH WILL EJECT EAST FROM THE LOW AS AN OPEN WAVE AS IT PROGRESSES DOWNSTREAM THROUGH THE INTERIOR WEST. THE CLOSED LOW IS FCST TO BE OFF THE NORTHERN CA COAST BY TH END OF DAY 2...WHEN THE PEAK LOW LEVEL JET IS OVER SOUTHERN CA. THE SOUTHWEST FLOW INCREASES PW VALUES TO 0.75 INCHES IN COASTAL SOUTHERN CA...WHERE ASCENT IN THE LEFT EXIT REGION OF A 100 KT 300 MB JET COMBINES WITH MOISTURE FLUXES TO PRODUCE MODERATE RAINFALL OVER SOUTHERN CA INTO THE SOUTHERN SIERRAS. THE CONTINUATION OF THE JET CORE ON DAY THREE SUPPORTS MORE SHOWERS ACROSS SOUTHERN CA...WITH THE JET EXTENDING INLAND ACRS THE SOUTHERN GREAT BASIN. THIS SUPPORTS MOISTURE FLUXES CONTINUING INTO THE GREAT BASIN...WITH A CORRESPONDING INCREASE IN PRECIPITATION. THE BETTER DEFINED CONVERGENCE AREAS ARE NEAR THE SOUTHERN CA COAST IN ADVANCE OF THE 850-700 MB LOW DRIFTING SOUTHEAST ALONG THE COAST...AND INLAND OVER THE SOUTHERN SIERRA ALONG THE UPPER JET TRAJECTORY. THE PRECIPITATION WILL BECOME MUCH MORE EXPANSIVE ACROSS THE WEST ON D3 BUT THE HEAVIEST AMOUNTS WILL CONTINUE ACROSS SOUTHERN CA...WHERE THE HIGHER PW VALUES PERSIST. THE GFS AMOUNTS ARE ANOMALOUSLY HIGH AND THE ECMWF/CANADIAN ON THE LOWER END. TO MITIGATE THESE DIFFERENCES...MANUAL PROGS USED A BLEND OF THE NAM/SREFMEAN/GLOBAL ENSEMBLE MEAN QPF. THE NAM CLOSED 700 MB LOW IS SLIGHTLY NORTH OF THE MODEL CONSENSUS...SO THE PRECIPITATION MAXIMA ON DAY THREE WAS NUDGED SOUTH OF THE NAM FORECAST IN CA. TERRY/PETERSEN GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV 24HR QP VT 05/12Z 0.01 465668 460657 456655 452654 443657 436664 431675 429687 433698 435702 439703 441706 443706 448702 453697 454691 458683 463672 465668 0.01 448746 447742 444742 440745 436749 424761 415772 410778 402782 386791 374802 364812 357823 353830 351835 352840 355842 358843 367840 373840 379836 382835 385831 390825 398821 403820 405821 411822 419823 431830 435833 438835 441835 445834 449831 450828 449821 445815 439809 435798 435791 435788 437771 438762 443756 447751 448746 0.01 474867 474861 471855 469852 466851 460850 455850 451851 436854 430855 422855 415854 409852 402851 396850 394854 399859 403868 409871 414873 418875 422875 429874 437872 443871 447872 452871 464873 468873 472871 474867 0.01 425695 422693 421692 419691 417691 415692 412694 410697 410702 413704 417705 418705 420704 422702 423701 424699 425695 0.01 378711 375707 371706 361712 351718 346722 344725 332741 328749 327753 328760 330769 334778 341786 344788 349787 355771 360767 366765 371763 374763 391765 393762 392759 385751 382749 379743 376732 378721 378711 0.01 403247 405244 406241 405234 402231 400227 401221 404216 403210 400208 384195 376188 368184 365187 365189 367193 369197 368201 363201 357199 349196 345192 342192 338193 336197 334221 335228 336232 342238 348241 353243 364245 375249 387252 396252 403247 0.25 355747 361740 363737 364733 363730 361729 359731 352739 348745 346749 347751 349751 355747 0.25 377228 376224 374220 369217 365214 361212 356210 353209 351211 349214 347220 349225 353228 356230 361233 366235 371234 375232 377228 24HR QP VT 06/12Z 0.01 522265 523258 521252 516249 513248 509248 507250 506254 502258 497255 485236 480230 483228 486228 490228 493226 495222 493215 488211 483210 472213 468211 467209 469204 475193 482187 486183 489179 491169 492157 490154 487153 484151 477151 470149 465148 460143 456139 449133 444131 440129 443121 448116 450114 450109 449104 447097 445093 442089 438088 433090 425096 421099 416100 413098 409093 400096 395098 394101 393105 378115 360125 361132 364137 368141 373144 377145 380148 388157 387161 385163 384168 385171 389174 393176 400179 405182 410184 417190 421195 421198 417198 413200 409199 404194 399192 395192 392190 387183 377178 372174 366172 351169 344161 338159 331159 327159 323161 320164 319167 320170 322183 326193 329202 333210 339219 345227 353234 359239 365243 369245 376248 381252 401262 425271 434273 442272 452268 462263 471257 479253 486250 487257 489263 496273 497281 500285 503286 510285 514282 518278 0.01 448751 447747 444744 440743 438745 436749 434754 433760 428759 426758 425761 425765 426769 429776 433780 436780 438777 437771 438767 441765 444762 447756 448751 0.01 423166 422165 420163 417164 414164 411164 408166 407167 408168 410169 413169 416169 419170 421170 422168 423166 0.01 370161 368158 368157 368154 366153 364153 363154 360156 359156 358160 359163 362164 365164 367164 368164 370161 0.25 450221 448217 446214 441213 438214 434217 432220 431225 431228 429230 423231 418229 417226 414218 411215 408213 383193 370184 363180 356180 349182 348182 346178 345170 343167 339165 333167 330172 330177 331184 333193 341206 347213 352217 357220 366224 373228 377230 381233 385238 392244 399248 408249 423250 431251 438249 440245 439241 433234 432232 434229 437229 444226 450221 0.50 411238 408233 408229 406225 401222 398223 394226 388227 388229 390233 395237 401239 404240 408241 411238 0.50 389205 386200 383196 379193 376191 372187 368185 363183 357183 354183 356187 359190 361192 365196 369200 372203 377205 382207 385207 389205 0.50 360213 361208 360204 355199 350194 347189 345182 344173 342170 339168 335173 335180 336187 338195 340202 345208 350212 354214 358214 360213 1.00 349203 349202 349200 348196 347194 345192 344191 343188 342186 341188 341191 341192 342195 343199 343200 344202 345204 348204 349203 24HR QP VT 07/12Z 0.01 495231 495226 494220 491211 483206 477205 471206 468206 464204 460202 457198 458195 461190 466183 468179 472179 481179 489178 492171 493166 499154 501150 500145 499139 496135 489129 482124 476119 472115 471109 469105 467102 464102 456101 453097 450094 440092 435092 430088 427087 425088 422091 422096 419100 415101 412091 412084 414081 418073 418065 416060 407054 402054 397055 390057 385058 382061 381068 372064 369065 366068 372085 384093 386097 387102 383108 375115 365117 359121 354127 350134 346139 340144 332147 323150 317154 310158 306165 304176 303186 303192 305196 307198 312200 321204 327209 333215 340220 349224 354229 369239 376243 379247 383250 387254 390255 400258 407257 413258 433258 441260 451259 469258 472258 478257 486254 489250 491245 492240 495231 0.01 444754 443750 442749 439748 436750 434753 433756 434760 435764 437767 439768 442767 443763 443762 444758 444755 444754 0.01 459856 457852 453850 449847 444846 441845 435847 433850 429855 427860 428864 430866 433866 436868 439868 442867 448867 454865 458860 459856 0.01 460131 461127 460126 458122 459118 458115 456118 455120 454122 452124 450126 449127 446129 446133 447138 448138 451138 454138 457136 458135 460132 460131 0.01 451080 450072 449066 447064 444056 441052 438051 430052 433056 439060 442064 439070 435072 436074 442076 447081 451080 0.01 429888 429884 427883 425881 424881 421879 420878 417877 414878 413882 416884 416885 419887 420887 422889 425889 426889 429890 429888 0.01 434200 434195 433191 432187 429189 421185 415179 413176 413171 411164 408160 405167 406156 406152 409148 413145 414141 413137 411133 405134 402136 400141 398143 398147 401157 402160 402163 399168 398175 400181 403185 406192 408195 413196 420195 426195 429199 433202 434200 0.25 489143 489139 489138 486137 484134 483133 481132 478129 475128 472128 472129 474133 474136 475137 477138 478137 480136 483138 486141 488143 489144 489143 0.25 473163 473158 470154 468151 466149 465148 463148 463153 464155 465157 467160 468162 470163 472163 473163 0.25 439247 439243 436241 432237 427235 417233 410230 407223 403225 401223 401220 403217 405214 404212 402208 380186 375181 368177 363175 358175 352178 349179 346171 344166 341164 334161 326160 322161 319163 317167 317173 320178 326192 331199 335204 345214 352218 360224 372225 381228 386229 390231 395235 401241 408246 417250 424251 429250 439247 0.25 447113 447109 447108 444106 441105 438105 435105 432105 429106 426106 424107 426111 427111 429112 432113 435113 438113 441114 443115 446114 447113 0.25 411222 412219 410217 407217 405217 407219 407221 409226 411222 0.25 388160 389155 389152 386145 381139 377133 372133 369140 365146 361153 361158 362163 365168 370173 374174 377173 383171 388164 388160 0.50 429244 427241 425238 422239 419239 417240 418242 421244 424245 427244 429244 0.50 389205 385197 379190 372183 369181 363179 358179 354180 348182 346178 345172 342167 339165 328163 325163 323165 323171 331186 335195 340203 346210 354215 357217 361217 363214 362210 359206 355200 354197 355195 361196 369201 374205 380207 385208 389205 1.00 372191 371188 370187 368185 365184 363183 360183 357183 356184 357185 359187 362187 365188 366189 367190 370191 372191 1.00 347196 346192 345186 344182 343177 342171 338170 335173 337180 337184 339190 341194 343198 347196 $$