000 FXUS04 KWBC 092153 QPFPFD QUANTITATIVE PRECIPITATION FORECAST DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 452 PM EST THU FEB 09 2012 FINAL DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION VALID FEB 10/0000 UTC THRU FEB 13/0000 UTC REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR DAY 1... UPDATED...THE 12Z ECMWF HAS THE BEST HANDLE ON THE ONGOING ACTVTY ALONG THE TX COAST WHERE NCEP GUIDANCE HAS LITTLE IF ANY PCPN EARLY IN THE PD. FOR THAT REASON LEANED THE FINAL DAY1 QPF MORE TWDS THE ECMWF SCENARIO INVOF THE NWRN GULF COAST. OTHERWISE..JUST VRY MINOR CHANGES WERE MADE BTWN THE PRELIM AND FINAL DAY1 QPF. ...PAC NW INTO THE NRN GT BASIN/NRN ROCKIES... IN THE BROAD SENSE..PATN RMNS RELATIVELY UNCHANGED OVR THIS PTN OF THE NATION THIS PD..WITH LONGWAVE H5 TROF PERSISTING OVR THE ERN PAC AND HI AMPITUDE H5 RDG CONTG OVR THE WRN STATES. WITHIN THIS ERN PAC TROF..THE MDLS BRING THE NEXT DEFINABLE S/WV INTO THE PAC NW LTR THU NGT THRU FRI AFTN..ACCOMPANIED BY A SURGE OF HIER PWS AND SOMEWHAT MORE FAVORABLE LOW LVL ONSHORE FLO. OTHER THAN SOME MINOR TIMING AND/OR STRENGTH DIFFS..THE LATEST MDL SOLNS ARE IN VRY GOOD AGREEMENT ON THIS SCENARIO..SO STUCK CLOSE TO THEIR REASONABLY SIMILAR QPFS. HVIEST PCPN SHLD BE ALG THE WA AND NRN OR CSTL RANGES..WHERE SOME LCLY GTR THAN 1.00 INCH RAINS XPCD..WITH LGTR QPF OVR INTO THE WA AND NRN OR CASCADES. H5 S/WV ENERGY DIVING SEWD DOWN FM THE NRN GT BASIN INTO THE NRN ROCKIES SHLD PRODUCE SOME ENHANCED HIER TERRAIN PCPN..BUT WITH WTR EQUIVALENTS GENLY ON THE LGT SIDE DUE MARGINAL MSTR AVBLTY. ...SRN PLAINS INTO THE WRN GULF CST STATES/LWR MS VLY... INITIAL CNTRL/SRN ROCKIES H5 S/WV HANDLED SIMILARLY BY THE LATEST MDLS..WITH ALL TAKING IT SEWD INTO THE SRN PLAINS BY LTR THU NGT/FRI MRNG..AND THEN MORE EWD/ESEWD INTO THE LWR MS VLY DURG THE DAY ON FRI. QUASI BAROCLINIC LEAF ALREADY DVLPG WITH THIS SYS..AND ALTHOUGH S/WV RMNS OPEN AND DOESN'T AMPLIFY THRU THE PD..IT WL PICK UP SOME ADDITIONAL GULF MSTR PTNS OF ERN TX INTO THE LWR MS VLY ON SOME INCREASE IN LOW LVL ONSHORE FLO. BTWN THE BAROCLINIC LEAF STRUCTURE AND THE IMPROVING GULF MSTR..XPC TWO AREAS OF ENHANCED PCPN..ONE BEING OVR THE SRN PLAINS AND THE OTHER FM ERN TX INTO LA. FOR THE MOST PART..MDL QPFS ARE IN DECENT AGREEMENT ON THIS..AND AGAIN DIDN'T DEVIATE MUCH FM THEM..WITH SOME 0.25-0.50 INCH WTR EQUIVALENTS LIKELY IN THE SRN PLAINS AND SOME LCLY GTR THAN 0.50 INCH RAINS XPCD ERN TX INTO WRN LA. ...E CST OF FL... THE AXIS OF SLGTLY ABV AVG PW VALUES WL RMN ACRS THE SRN HALF OF FL THIS PD. SCTTD SHWRS SHLD PERSIST IN THIS HIGH PW AXIS AS LIFT MAY BE ACCENTUATED BY WK S/WVS IN THE WSWLY FLO ALOFT ACRS THE GULF OF MEXICO INTO THE FL PENINSULA. STILL HAVE LOW CONFIDENCE ON QPF DETAILS...WITH GENLY LGT AREAL AVG AMTS DEPICTED..BUT WITH SOME ISOLATED MDT TO HVY TOTALS PSBL ACRS PTNS OF THE FL E CST. ...GTLKS... STG CDFNT MOVG THRU FOLLOWED BY SOME ENHANCED LK EFFECT AT LEAST ACRS THE NRN GTLKS SHLD PRODUCE WIDESPREAD AND GENLY LGT PCPN MUCH OF THE REGION..WITH ANY MORE SIGNIFICANT TOTALS LIKELY LEE OF LK SUPERIOR IN THE STG LOW LVL CAA LTR FRI MRNG/AFTN. DAYS 2 AND 3... ...PACIFIC NORTHWEST... LINGERING SHORTWAVE ENERGY NEAR WASHINGTON EARLY ON SATURDAY IS EVENTUALLY CAUGHT UP IN NORTHERLY FLOW ON THE HEELS OF A SHORTWAVE ENTERING THE FOUR CORNERS REGION. MOISTURE/ONSHORE FLOW WEAKENS EARLY IN THE DAY 2 PERIOD...00Z/11...WITH REMAINING QPF ON THE LIGHT SIDE. MINOR TIMING DIFFERENCES WITH THE NEXT SHORTWAVE TO REACH THE NORTHWEST COAST WILL BRING MEASURABLE QPF TO THE PAC NW COAST BY THE END OF THE DAY 3 PERIOD IN LINE WITH THE 12Z ECMWF. ...NRN ROCKIES INTO THE CENTRAL HIGH PLAINS... MODIFIED ARCTIC AIR MASS AND STRONG HIGH PRESSURE IN PLACE TO THE EAST OF THE CONTINENTAL DIVIDE FRIDAY EVENING WILL LIKELY ENSURE ONGOING UPSLOPE ENHANCED SNOW SHOWERS AT THE START OF THE DAY 2 PERIOD...00Z/11. MID-LEVEL VORTICITY DROPPING DOWN THE EAST SIDE OF A MID/UPPER LEVEL ALBERTA RIDGE WILL BECOME INCREASINGLY SHEARED WITHIN A MOISTURE STARVED ENVIRONMENT. UPSLOPE WIND COMPONENT NOT VERY STRONG WHICH WILL LIMIT LIQUID EQUIVALENTS BEFORE AN EASTWARD MOVING REX BLOCK ENDS UPSLOPE SNOW SHOWERS. HPC FOLLOWED A GENERAL MODEL COMPROMISE FOR QPF LED BY THE 12Z ECMWF/UKMET. PLEASE SEE THE QPFHSD FOR SNOWFALL DETAILS. ...GREAT BASIN INTO SRN PLAINS... OPERATIONAL MODELS ARE IN A BIT BETTER AGREEMENT WITH RESPECT TO THE SHORTWAVE TROUGH REACHING THE GREAT BASIN ON SUNDAY WITH THE LINGERING BAJA CLOSED LOW GETTING "KICKED" OUT INTO THE SOUTHERN PLAINS. WITH WITH THE MIDDLE OF THE SPREAD REGARDING TIMING DIFFERENCES...CLOSE TO A 12Z ECMWF/UKMET BLEND. TRACK OF THE 700MB LOW FAVORS THE HIGHER TERRAIN OF THE WASATCH...CO ROCKIES AND SAN JUANS. BY EARLY SUNDAY...EASTERLY FLOW ON THE SOUTH SIDE OF AN 850 MB LOW OVER EAST TEXAS BRINGS GULF MOISTURE UP THE RIO GRANDE VALLEY AND NORTHWARD ACROSS THE SRN HIGH PLAINS. THIS MOISTURE WILL OVERRUN SHALLOW COLD AIR SITUATED ACROSS THE LONE STAR STATE WITH SHOWERS INCREASING BY 00Z/13. HPC QPF FOLLOWED THE MIDDLE OF THE GROUND SPEED SUPPORTED BY THE 12Z ECMWF/UKMET/CMC. ...OH VALLEY INTO THE MID ATLC AND NORTHEAST... MID-LEVEL SHORTWAVE TROUGH SWINGING ACROSS THE GREAT LAKES AND NORTHERN MID-ATLANTIC ON SATURDAY WILL HELP CARRY A STRONG COLD FRONT EASTWARD WITH MOSTLY SNOW ACROSS THE REGION WITH LOCALLY OROGRAPHICALLY ENHANCED QPF INTO WEST VIRGINIA AND THE NRN APPALACHIANS. IN ADDITION...A SURFACE LOW IS FORECAST TO DEVELOP NEAR THE MID-ATLANTIC COAST EARLY SAT MORNING AND TRACK NORTHEASTWARD UP THE WESTERN ATLANTIC. RECENT MODEL TRENDS HAVE SHIFTED WEST WITH THE ASSOCIATED SURFACE LOW TOWARD THE 40N/70W BENCHMARK WHICH IS INCREASING CONFIDENCE IN LIGHT TO MODERATE QPF FOR SRN NEW ENGLAND...MOSTLY IN THE FORM OF SNOW. HAVE SHIFTED QPF WESTWARD FROM CONTINUITY IN LINE WITH A 12Z GFS/12Z UKMET BLEND. THINKING THAT AS THE LOW STRENGTHENS...DEFORMATION ZONE PCPN WILL INCREASE AS ATLANTIC MOISTURE IS TAPPED WITH LOW LEVEL FLOW TAKING MOISTURE WESTWARD OVER SOUTHEASTERN PORTIONS OF NEW ENGLAND AND LONG ISLAND WITH LOCALLY HEAVIER BANDS DEVELOPING JUST AS THE LOW IS EXITING THE REGION. HIGHEST QPF IS PAINTED OVER SOUTHEASTERN MASS AND EASTERN MAINE BUT POTENTIAL FUTURE WESTWARD TRENDS OF THE SURFACE LOW COULD PULL HEAVIER QPF WESTWARD ACROSS THE NORTHEAST. PLEASE SEE THE QPFHSD FOR SNOW ACCUMULATION DETAILS. ...GREAT LAKES... COLD AIR WILL BE ENTRENCHED ACROSS THE UPPER GREAT LAKES BY FRIDAY NIGHT BEHIND A MODIFIED ARCTIC FRONT LEADING TO LAKE EFFECT SNOW SHOWERS. BRIEF WINDOWS OF MINIMAL LOW LEVEL WIND SHEAR...MOISTURE AND FCST OMEGA WITHIN THE DENDRITIC GROWTH ZONE IMPACT LOCATIONS SOUTH OF LAKE MICHIGAN AND ACROSS SUPERIOR INTO THE MICHIGAN U.P. AND NORTHWESTERN LOWER MICHIGAN EARLY SATURDAY. THEREAFTER...SAVE FOR THE 12Z GFS BY 00Z/13...THE LOW TO MID LEVEL FLOW BECOMES MORE NORTHWESTERLY FAVORING THE LOWER LAKES WITH LIGHT TO MODERATE SNOW. PLEASE SEE THE QPFHSD FOR SNOW ACCUMULATION DETAILS. TERRY/OTTO GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV 24HR QP VT 11/00Z 0.01 505710 504703 501698 496697 493697 489700 485706 476723 466739 462746 459752 453762 444775 435785 423793 419794 416793 414792 411788 408780 402778 398779 396781 391788 388795 386799 381809 378814 374822 370832 365845 359858 350869 344875 338880 328884 321886 315884 307881 295881 284887 271895 262903 254914 250922 249928 248934 247939 249945 251951 255955 259958 260960 259963 255967 252972 252976 253981 257982 264979 268978 270980 272984 272988 272993 273998 274000 278000 284997 288996 291998 299005 302011 304015 304025 303031 302041 305048 307050 312050 322049 329048 342053 349055 354055 358052 359047 348042 342039 337035 333029 334023 336021 342017 348014 353012 356009 361005 364001 370991 374985 376979 379973 381969 381966 382957 382949 383944 382938 379929 378926 379923 381914 383899 387894 393890 398888 402885 414877 424886 430889 438886 443883 451885 454892 456905 457914 459919 462920 466918 470913 479887 488853 491842 492831 495813 498782 499765 499747 503726 505710 0.01 525256 522245 521234 522230 525228 533223 536221 538209 537196 532185 526175 520167 493129 488121 484113 480102 476094 473088 470085 468086 464085 461079 459072 455068 450064 446063 438064 434069 436073 442080 438085 435088 432088 425079 423073 425067 427062 426057 421049 418047 413046 406049 402053 400057 398061 396064 396068 394081 394084 397084 400084 402086 403091 402095 403102 398107 391112 391116 393116 396116 400117 408120 414122 417125 421130 426133 430131 434127 437127 439133 438139 439145 441149 446153 452158 458159 461163 463170 465174 474180 479184 481187 479193 475198 472202 467203 459206 452211 443214 437213 433214 425224 422228 418224 418219 417212 413210 409210 402212 399215 398219 394222 389221 386220 383222 380225 376228 375232 378238 381242 397253 404256 415259 436264 447266 459271 467275 476282 484286 491289 505291 510291 515286 0.01 425099 425096 424095 421094 418095 416099 415102 415103 415104 418107 421104 421103 424101 425099 0.01 321792 318785 313782 308781 306778 297770 289764 284762 278763 268764 264768 262774 261778 258783 252792 247800 243810 242814 242821 243824 246825 248822 252819 257816 261813 266815 273819 278822 284823 288824 294823 300818 304814 310807 318797 321792 0.25 516272 519262 518253 514241 511234 507226 502218 499215 496214 488214 483214 479214 469218 464221 460224 457228 453230 443232 437232 431235 428236 422237 418238 416243 417246 422249 429250 452254 463260 468264 474267 484273 495281 502283 507282 514275 516272 0.25 527203 525200 522197 521201 522203 524205 527203 0.25 483138 481133 480133 478132 475132 474133 475135 477137 480139 483138 483138 0.25 345982 343979 342979 341980 339980 337982 335984 335987 336991 338992 340990 343988 345986 345983 345982 0.25 343952 342950 339952 338953 336954 335957 337958 340956 342953 343952 0.25 320933 316910 313901 307898 304894 301893 296896 293906 291913 293925 292932 290942 288949 284962 282972 283976 286976 293971 299966 303961 307955 311948 315942 319936 320933 0.25 285801 283797 280793 277791 274789 270788 266789 264791 262794 262798 263800 267802 271803 274804 277805 283804 285801 0.50 513271 516264 516256 513247 510240 506232 500225 496221 493224 492231 490233 488234 483234 479230 475230 471232 465234 458236 454235 451236 448237 448242 454245 461250 467256 472259 481265 486269 494276 501280 506278 509275 513271 0.50 444240 442239 440238 437238 436238 436240 439240 442240 444240 0.50 429244 427242 424242 427244 429244 0.50 311931 310922 308912 305911 301911 299913 298918 297925 296931 295940 293948 292955 295961 300957 303953 307946 309941 311933 311931 1.00 504272 504266 502262 498255 493249 490242 487242 484244 481243 479240 478238 474237 474242 478248 479252 482255 487262 492267 498274 502275 504272 1.00 508254 509250 508245 507244 505240 504239 502237 500235 499232 497231 497232 499237 499238 502240 503243 504247 505248 506253 506254 508254 1.50 501270 500269 500265 498263 497259 496258 494255 492253 491252 488250 487251 488256 490259 492262 492263 495265 497269 500271 501270 24HR QP VT 12/00Z 0.01 486628 483621 481619 478616 475612 472610 469607 465605 460608 452614 447621 439632 435640 428647 422652 411661 392673 384679 375685 367690 361693 352698 342703 337705 328710 321717 316721 312723 303728 299730 296733 285747 269766 260777 255783 252790 248788 244790 242794 240800 239808 238816 239822 246821 250817 257806 263802 267800 270801 272805 272808 269815 269822 262828 255832 250838 246845 246852 244867 243876 244886 245899 246908 247913 249915 255918 258919 262919 271917 279913 294905 302900 307894 315881 317876 318867 319859 319854 318850 312834 311830 311827 314819 317814 324807 334803 340802 350803 357802 362800 366800 364806 360815 356822 349834 347842 348848 349859 351864 354866 360869 362874 363882 366886 369888 377886 384882 388879 391877 411855 418848 424841 436827 442825 447828 453832 458839 450843 445847 443850 440855 436859 431860 426861 419861 414862 411867 410873 414877 421878 428877 437875 442874 446871 451867 456871 459873 460879 464885 462892 465896 467896 470890 475885 478883 482878 483875 484867 484857 484851 482844 478838 472832 465827 459820 455810 454803 451798 446801 443798 444788 448779 452771 460753 470734 480715 487699 491691 493686 494681 495671 493667 491665 486664 487659 487647 486628 0.01 520269 520260 519253 516246 513243 512240 507226 507221 509219 514217 522210 526208 527202 524198 523193 523188 520182 516176 513174 509169 506162 503155 500149 494139 487125 479112 472103 462082 456071 453065 451057 447043 443038 438034 434030 430024 424015 416006 410002 404000 400997 395996 392995 388997 386003 382008 380015 380020 382024 389032 393037 395041 397049 397056 397060 395064 394068 395076 400077 407078 414079 421079 425081 428083 430087 431095 429102 428109 437119 438124 438131 439135 437139 434144 432147 430147 428146 426140 422134 419130 416131 410133 400139 395143 394143 392146 390144 388145 385148 379155 373166 367177 363179 355179 351180 347180 344178 340175 336173 332173 332176 337184 341195 345199 350202 357204 362201 372207 379208 384214 387217 387220 385221 381222 377222 368217 360217 355218 354222 356226 368233 387247 390245 395245 408251 420253 426252 431252 444254 456257 464266 472277 479285 484290 487292 493295 497296 501295 504293 509290 511289 513286 515278 520269 0.01 407175 409171 408168 405167 402167 398170 395173 392176 394180 394188 394191 392195 396197 399193 401189 403186 406179 407175 0.25 453653 452649 450647 445647 440649 434654 412671 401679 389688 378697 367703 357707 351711 345715 328730 321734 315736 309740 304747 298756 295765 294770 291775 285783 283792 284798 285802 287805 296810 300811 305808 316801 354775 359771 365767 371764 375761 386752 397748 402745 405740 412731 418722 432700 444681 448673 451666 454658 453653 0.25 505267 504262 503255 501242 499237 497231 492227 489226 487228 482230 480228 477228 473230 468227 465226 463230 461233 460237 460241 462246 467253 473257 478259 487260 495265 498268 501268 505267 0.25 462182 464178 463174 463173 460171 457170 455168 454168 452167 451167 448169 447170 446174 445178 444180 443182 444184 447186 450187 452187 455186 458185 459185 462182 462182 0.25 395802 392801 392799 389800 387801 384803 383807 385808 388806 390804 393803 395802 0.25 419049 418045 416041 415037 415036 412034 410038 409041 409045 411049 412051 414053 415053 416053 418051 419049 0.25 284867 283862 281858 279857 276859 273864 272871 269878 266882 263889 264893 267896 272896 275894 280888 282884 283877 284868 284867 0.50 438667 436663 432662 421668 413674 404681 397690 392699 387703 383705 376708 366713 356720 348726 346730 346735 339742 332748 328752 323754 319755 315759 311765 306774 302780 299788 295796 294800 297802 304803 308802 313799 320795 329788 335782 339776 343772 345768 349764 355762 363758 366754 370751 390739 395736 398731 401723 404714 408709 413705 419699 425691 434678 437671 438667 0.50 476242 475240 473237 469238 466239 465239 466242 466243 468245 471246 473246 475243 476242 1.00 366742 364742 361744 359746 356747 354749 354750 357750 360748 362747 365745 366742 1.00 327771 325770 322771 319773 317775 315777 314777 316779 318778 321776 323775 325773 327771 1.00 325783 323782 320783 317784 315786 314788 316790 317790 319790 321788 322788 324785 325783 24HR QP VT 13/00Z 0.01 508644 505635 501631 494624 486609 482602 478597 474596 468600 465601 460605 451615 445619 439625 424645 406665 398672 389680 378689 367696 360704 354711 346721 342725 340730 338739 342746 345750 350751 358753 362753 367755 373758 383761 387762 393762 407721 412717 416715 421714 426712 435709 448701 467690 487681 492678 497673 505664 507660 508654 508644 0.01 523265 518253 511238 505226 500212 497209 493209 488211 476212 472213 470216 471225 472228 470229 464231 461230 459233 455236 450239 442239 438239 433241 427243 423246 416256 414263 416271 416277 420281 426286 433290 457291 463290 468290 474290 481292 486292 492293 505295 511296 0.01 533205 531193 527184 522175 516169 510163 504159 497153 491145 487138 481133 475133 471133 466132 461131 456136 447153 443161 443169 439176 438178 433178 426180 424178 422174 419171 417169 415171 413177 414184 415193 413199 416203 421202 427199 428195 431187 435187 437190 441193 446192 453192 459187 462183 464182 470185 475186 480188 485192 490195 495195 502196 511198 517201 520206 523209 527209 530206 533205 0.01 477861 476853 475845 472836 467829 462823 459819 458813 455805 454800 450795 445788 442782 442777 443772 444765 446757 445752 443750 436750 429748 426747 423749 420755 421763 421768 418773 413778 407783 401789 394794 392799 397801 405800 408800 409803 411808 411810 411816 413820 415821 417823 418821 420818 424814 426817 427823 430826 432826 439828 441830 442837 443841 441846 442853 443857 446859 452863 462872 467876 471873 473869 476865 477861 0.01 447105 447098 444096 437095 432092 429089 429083 436077 436070 434067 430064 427058 424055 417053 404053 400053 401047 400043 398038 390040 379041 375043 374047 377050 382053 384054 376055 366051 364049 360048 358048 353047 349044 348040 351037 354033 356029 357021 359016 365010 372000 373996 372992 369987 365987 355984 337989 314993 308992 304991 295985 288980 282973 276966 271961 265956 258951 255949 250947 239948 233964 231973 232981 235992 236996 237002 241011 246021 252027 259031 266035 272040 279044 285050 292056 300062 308067 317071 321080 324089 326100 328110 332119 340126 389172 406163 420166 429173 431173 433170 431164 427160 426158 430143 433131 435119 438111 441107 447105 0.01 393057 393053 392053 390053 389054 389057 392057 393057 0.01 379196 379192 376189 374182 369178 362178 354179 349182 346189 348196 350199 352200 354198 360195 364192 370196 375199 379196 0.01 344175 344168 339162 334157 329155 323155 315155 309158 309162 313168 318171 324176 329180 337182 340181 342178 344175 0.25 492642 487635 481628 475621 471620 467621 463621 459624 451628 446632 443637 438645 429662 424669 421675 421681 421684 423689 426691 431690 437688 446683 454681 462678 480663 488653 491649 493643 492642 0.25 508278 510272 510268 505262 491251 480257 475260 466260 460260 453261 441265 439270 439272 445274 462277 471281 477281 492282 498280 501280 504281 508278 0.25 420141 418145 419146 420145 422144 423142 422138 421138 420141 0.25 406114 408107 406103 401095 398089 398086 401081 402077 402072 397070 392070 387071 383070 378068 375066 369065 366066 364072 364078 366083 372088 381090 384093 385098 382106 377112 374115 370117 368123 371126 376128 380128 388126 396124 403119 406114 0.25 344014 343009 339008 331011 325012 317016 312020 306023 301027 301031 303033 307034 312032 321029 326027 332025 337021 342016 344014 0.25 273007 273003 272000 269995 265987 262981 262978 257970 252967 246966 242969 240975 240982 241990 245001 251012 257018 260019 263018 266014 273007 0.50 481638 477631 472626 467625 462626 457628 450634 443648 438660 435665 429672 429678 431682 434682 438680 442677 449674 456670 462665 468658 474653 480646 481642 481638 0.50 392113 392109 389112 388112 388116 389116 391114 392113 0.50 380079 379075 378074 375073 372074 371075 372079 372080 375083 378082 380079 1.00 467631 466631 463632 460633 457634 455637 454639 453640 452645 452646 454648 456647 459645 461643 464641 466638 467636 468634 467631 $$